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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Pathol. Oncol. Res.</journal-id>
<journal-title-group>
<journal-title>Pathology &#x26; Oncology Research</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Pathol. Oncol. Res.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1532-2807</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">1612328</article-id>
<article-id pub-id-type="doi">10.3389/pore.2026.1612328</article-id>
<article-version article-version-type="Version of Record" vocab="NISO-RP-8-2008"/>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Systematic Review</subject>
</subj-group>
</article-categories>
<title-group>
<article-title>Multimodal prehabilitation for upper gastrointestinal tumors: effects on postoperative morbidity and mortality &#x2013; a meta-analysis of randomized controlled trials</article-title>
<alt-title alt-title-type="left-running-head">Papp et al.</alt-title>
<alt-title alt-title-type="right-running-head">
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/pore.2026.1612328">10.3389/pore.2026.1612328</ext-link>
</alt-title>
</title-group>
<contrib-group>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Papp</surname>
<given-names>Csenge</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="corresp" rid="c001">&#x2a;</xref>
<uri xlink:href="https://loop.frontiersin.org/people/3229288"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Csontos</surname>
<given-names>Armand</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/2184843"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Kehl</surname>
<given-names>Daniel</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Sindler</surname>
<given-names>Lili Dora</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Vereczkei</surname>
<given-names>Andras</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Papp</surname>
<given-names>Andras</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group>
<aff id="aff1">
<label>1</label>
<institution>Department of Surgery, Clinical Center, University of P&#xe9;cs</institution>, <city>P&#xe9;cs</city>, <country country="HU">Hungary</country>
</aff>
<aff id="aff2">
<label>2</label>
<institution>Faculty of Business and Economics, University of P&#xe9;cs</institution>, <city>P&#xe9;cs</city>, <country country="HU">Hungary</country>
</aff>
<author-notes>
<corresp id="c001">
<label>&#x2a;</label>Correspondence: Csenge Papp, <email xlink:href="mailto:pappcse@gmail.com">pappcse@gmail.com</email>
</corresp>
</author-notes>
<pub-date publication-format="electronic" date-type="pub" iso-8601-date="2026-04-28">
<day>28</day>
<month>04</month>
<year>2026</year>
</pub-date>
<pub-date publication-format="electronic" date-type="collection">
<year>2026</year>
</pub-date>
<volume>32</volume>
<elocation-id>1612328</elocation-id>
<history>
<date date-type="received">
<day>15</day>
<month>12</month>
<year>2025</year>
</date>
<date date-type="rev-recd">
<day>08</day>
<month>04</month>
<year>2026</year>
</date>
<date date-type="accepted">
<day>17</day>
<month>04</month>
<year>2026</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#xa9; 2026 Papp, Csontos, Kehl, Sindler, Vereczkei and Papp.</copyright-statement>
<copyright-year>2026</copyright-year>
<copyright-holder>Papp, Csontos, Kehl, Sindler, Vereczkei and Papp</copyright-holder>
<license>
<ali:license_ref start_date="2026-04-28">https://creativecommons.org/licenses/by/4.0/</ali:license_ref>
<license-p>This is an open-access article distributed under the terms of the <ext-link ext-link-type="uri" xlink:href="https://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution License (CC BY)</ext-link>. The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</license-p>
</license>
</permissions>
<abstract>
<sec>
<title>Background</title>
<p>Patients suffering from upper gastrointestinal (UGI) cancers often present with malnutrition and frailty before undergoing major surgical procedures, which significantly elevates the risk of postoperative complications. Prehabilitation focuses on optimizing a patient&#x2019;s functional capacity before surgery to improve postoperative outcomes. Our goal was to synthesize the effects of prehabilitation on the postoperative outcomes of UGI cancer patients undergoing major surgical intervention using a systematic review and meta-analysis.</p>
</sec>
<sec>
<title>Methods</title>
<p>A comprehensive systematic search was conducted across the PubMed, Embase, Cochrane, and Scopus databases to identify relevant randomized controlled trials (RCTs). Ten RCTs, encompassing data from 878 patients, were included in the analysis. Pooled risk ratios (RRs) were calculated for dichotomous variables (e.g., incidence of complications), and weighted mean differences were calculated for continuous variables using a random-effects model. Study quality was assessed using the RoB2 and GRADE approaches.</p>
</sec>
<sec>
<title>Results</title>
<p>The meta-analysis showed a trend toward a lower incidence of minor postoperative complications (Clavien&#x2013;Dindo Grade I&#x2013;II) in the prehabilitation group. While the common effect model showed significance, the certainty of evidence remains low to very low for most outcomes, suggesting these results should be interpreted with caution. However, a significant reduction was found in Grade III complications when using a common effect model, although no significant differences were detected in Grade IV complications or mortality. Cardiovascular complications and hospital readmission rates also showed no significant disparity.</p>
</sec>
<sec>
<title>Conclusion</title>
<p>The implementation of prehabilitation in UGI cancer patients is safe and shows a positive trend toward reducing minor postoperative complications, thereby enhancing patient comfort and potentially accelerating recovery time. While the certainty of evidence remains low, further high-quality RCTs with larger patient cohorts are warranted, especially to explore the role of multimodal prehabilitation.</p>
</sec>
</abstract>
<kwd-group>
<kwd>ERAS protocol</kwd>
<kwd>meta-analysis</kwd>
<kwd>postoperative complications</kwd>
<kwd>prehabilitation</kwd>
<kwd>upper gastrointestinal cancers</kwd>
</kwd-group>
<funding-group>
<funding-statement>The author(s) declared that financial support was not received for this work and/or its publication.</funding-statement>
</funding-group>
<counts>
<fig-count count="10"/>
<table-count count="4"/>
<equation-count count="0"/>
<ref-count count="15"/>
<page-count count="11"/>
</counts>
</article-meta>
</front>
<body>
<sec sec-type="intro" id="s1">
<title>Introduction</title>
<p>It is essential to evaluate the nutritional and physical condition of patients with malignant diseases before surgery, particularly for those with upper gastrointestinal (UGI) cancers. These tumors often lead to swallowing difficulties, which can quickly induce a catabolic state even before the operation [<xref ref-type="bibr" rid="B1">1</xref>]. The World Health Organization reported approximately 541,019 new cases of oesophageal cancer and 1,002,136 new cases of stomach cancer globally in 2022 [<xref ref-type="bibr" rid="B2">2</xref>]. Upper gastrointestinal tract cancers represent a significant global health issue, ranking as the 6th most common cause of cancer-related deaths worldwide in 2020 [<xref ref-type="bibr" rid="B3">3</xref>].</p>
<p>Risk factors for these cancers include smoking, alcohol consumption, poor diet, and infection by specific bacteria or viruses, such as <italic>Helicobacter pylori</italic> and human papillomavirus (HPV). For example, HPV infection is a prognostic factor in oropharyngeal squamous cell carcinomas (SCC), where altered miRNA expression patterns have been identified in both tumor tissues and surrounding mucosa. Preventive strategies include quitting smoking, reducing alcohol intake, adopting a healthy diet, and receiving the HPV vaccine [<xref ref-type="bibr" rid="B4">4</xref>, <xref ref-type="bibr" rid="B5">5</xref>].</p>
<p>Recently, there has been dynamic progress in the multidisciplinary treatment of cancer patients, and we expect that the development and implementation of a new protocol system for nutritional therapy will become widespread and significantly contribute to further advancements. Applying an appropriate nutritional protocol can improve tissue repair, support the proper functioning of the immune system, and reduce the risk of complications [<xref ref-type="bibr" rid="B6">6</xref>, <xref ref-type="bibr" rid="B7">7</xref>].</p>
<p>Malnutrition is one of the main factors contributing to mortality in these patients [<xref ref-type="bibr" rid="B7">7</xref>, <xref ref-type="bibr" rid="B8">8</xref>]. Therefore, it is essential to address overall condition of the patients not only after surgery, but also before it. Prehabilitation represents a frequently neglected but, we believe, vital element of the ERAS (Enhanced Recovery After Surgery) protocol, which can be crucial in the preoperative period, especially for patients with stomach and oesophageal cancers. It is important to note here, the present study does not wish to discuss the entire ERAS protocol as instead, it focuses on the prehabilitation phase. However, in <xref ref-type="table" rid="T1">Table 1</xref> we marked those RCTs where the entire ERAS protocol was applied. The goal of prehabilitation is to prepare patients physically and psychologically for a major surgery [<xref ref-type="bibr" rid="B9">9</xref>, <xref ref-type="bibr" rid="B10">10</xref>].</p>
<table-wrap id="T1" position="float">
<label>TABLE 1</label>
<caption>
<p>Comparison of prehabilitation types, ERAS status, and study intervals.</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="left">Author</th>
<th align="left">Prehabilitation</th>
<th align="left">ERAS</th>
<th align="left">Surgery</th>
<th align="left">Sample Size (I/C)</th>
<th align="left">Initiation of prehabilitation</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="left">Guinan et al.</td>
<td align="left">Physical</td>
<td align="left">&#x2b;</td>
<td align="left">Esophagectomy</td>
<td align="left">28/32</td>
<td align="left">&#x2265;2 weeks preoperative</td>
</tr>
<tr>
<td align="left">Valkenet et al.</td>
<td align="left">Physical</td>
<td align="left">-</td>
<td align="left">Esophagectomy</td>
<td align="left">95/121</td>
<td align="left">&#x2265;2 weeks preoperative</td>
</tr>
<tr>
<td align="left">Zylstra et al.</td>
<td align="left">Physical</td>
<td align="left">-</td>
<td align="left">Esophagectomy</td>
<td align="left">21/19</td>
<td align="left">Started before neoadjuvant therapy</td>
</tr>
<tr>
<td align="left">Kong et al.</td>
<td align="left">Nutritional</td>
<td align="left">-</td>
<td align="left">Gastrectomy</td>
<td align="left">65/62</td>
<td align="left">2 weeks preopereative</td>
</tr>
<tr>
<td align="left">Liu et al.</td>
<td align="left">Nutritional</td>
<td align="left">&#x2b;</td>
<td align="left">Esophagectomy</td>
<td align="left">26/24</td>
<td align="left">1 week preoperative</td>
</tr>
<tr>
<td align="left">Loughney et al.</td>
<td align="left">Physical</td>
<td align="left">-</td>
<td align="left">Gastrectomy or esophagectomy</td>
<td align="left">36/35</td>
<td align="left">Started before neoadjuvant therapy</td>
</tr>
<tr>
<td align="left">Yamana et al.</td>
<td align="left">Physical</td>
<td align="left">-</td>
<td align="left">Esophagectomy</td>
<td align="left">30/30</td>
<td align="left">&#x2265;1 week preoperative</td>
</tr>
<tr>
<td align="left">Minnella et al.</td>
<td align="left">Nutritional, physical</td>
<td align="left">&#x2b;</td>
<td align="left">Gastrectomy or esophagectomy</td>
<td align="left">26/25</td>
<td align="left">Followed ERAS principles</td>
</tr>
<tr>
<td align="left">Allen et al.</td>
<td align="left">Nutritional, physical, psychological</td>
<td align="left">-</td>
<td align="left">Gastrectomy or esophagectomy</td>
<td align="left">26/28</td>
<td align="left">15-week preoperative program</td>
</tr>
<tr>
<td align="left">Bausys et al.</td>
<td align="left">Nutritional, physical, psychological</td>
<td align="left">-</td>
<td align="left">Gastrectomy</td>
<td align="left">64/64</td>
<td align="left">4 weeks preoperative</td>
</tr>
</tbody>
</table>
</table-wrap>
<p>The use of prehabilitation is becoming increasingly accepted in contemporary medicine, as evidenced by numerous international publications. Based on these studies, we planned a meta-analysis to summarize the impact of prehabilitation on patients with upper gastrointestinal cancers. The aim of our study is to examine the effects of prehabilitation in upper gastrointestinal cancer patients preparing for major surgical interventions.</p>
</sec>
<sec sec-type="materials|methods" id="s2">
<title>Materials and methods</title>
<sec id="s2-1">
<title>Protocol registration</title>
<p>The protocol of the meta-analysis methods was registered in database of Prospero previously in the number of 653422. The acceptance of registration was in 2025.02.24.</p>
</sec>
<sec id="s2-2">
<title>The question of the review</title>
<p>The aim of the meta-analysis is defined in PICO protocol. The included patients (P) underwent upper gastrointestinal surgery because of malignancy. The intervention (I) group underwent physical or nutritional prehabilitation before surgery, while the control (C) group received no preoperative intervention. We examined the outcome of postoperative mortality, morbidity and performance status.</p>
</sec>
<sec id="s2-3">
<title>Search strategy and selection process</title>
<p>The goal was to identify randomized controlled examinations (RCTs) therefore comprehensive scans were performed in the databases of PubMed, Embase, Cochrane and Scopus. We defined search keys containing &#x201c;oesophagus cancer&#x201d;, &#x201c;esophagectomy&#x201d;, &#x201c;prehabilitation&#x201d;, &#x201c;physical examination&#x201d; and &#x201c;nutrition&#x201d; and their variants. The screening process was conducted in two stages. First, two independent reviewers (Cs.P. and A.Cs.) screened all titles and abstracts identified by the search. In the second stage, the full texts of potentially relevant articles were retrieved and assessed for eligibility based on the inclusion and exclusion criteria. EndNote ver. x9.3.3; Alfasoft AB, G&#xf6;teborg, Sweden) software was used to manage records and identify duplicates. Any disagreements between the reviewers during the screening or data extraction process were resolved through discussion or by consulting a third senior reviewer (A.P.). The screening and selection process is summarized in <xref ref-type="fig" rid="F1">Figure 1</xref>.</p>
<fig id="F1" position="float">
<label>FIGURE 1</label>
<caption>
<p>PRISMA flowdiagram of study selection and inclusion.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g001.tif">
<alt-text content-type="machine-generated">Flow diagram illustrating a systematic review process: 9,555 records identified, 1,293 duplicates removed, 8,262 screened, 8,205 excluded, 57 reports sought, 13 not retrieved, 44 assessed, 34 excluded, 10 studies included.</alt-text>
</graphic>
</fig>
<p>The systematic search was conducted in December 2024. We employed a combination of Medical Subject Headings (MeSH) terms and Emtree keywords, along with free-text terms relevant to &#x201c;esophageal cancer,&#x201d; &#x201c;gastric cancer,&#x201d; &#x201c;prehabilitation,&#x201d; and &#x201c;postoperative complications.&#x201d; No language restrictions were applied to minimize publication bias. The complete electronic search strings for all databases and the specific search dates are provided in <xref ref-type="table" rid="T2">Table 2</xref>.</p>
<table-wrap id="T2" position="float">
<label>TABLE 2</label>
<caption>
<p>Search strategy.</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="left">Search component</th>
<th align="left">Description</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="left">Search date</td>
<td align="left">December 2024</td>
</tr>
<tr>
<td align="left">Databases</td>
<td align="left">PubMed, embase, cochrane library, scopus</td>
</tr>
<tr>
<td align="left">Language restrictions</td>
<td align="left">None (no filters applied for language)</td>
</tr>
<tr>
<td align="left">Study design</td>
<td align="left">Randomized controlled trials (RCTs)</td>
</tr>
<tr>
<td align="left">Controlled vocabulary</td>
<td align="left">MeSH (PubMed), emtree (embase)</td>
</tr>
<tr>
<td align="left">Search filters</td>
<td align="left">Human subjects only</td>
</tr>
<tr>
<td align="left">Search strings</td>
<td align="left">(&#x201c;Esophageal Neoplasms&#x201d; [MeSH] OR &#x201c;stomach Neoplasms&#x201d; [MeSH] OR &#x201c;esophageal cancer&#x201d; OR &#x201c;gastric cancer&#x201d; OR &#x201c;upper gastrointestinal cancer&#x201d;) AND (&#x201c;Prehabilitation&#x201d; [All fields] OR &#x201c;preoperative Care&#x201d; [MeSH] OR &#x201c;exercise Therapy&#x201d; [MeSH] OR &#x201c;nutritional Support&#x201d; [MeSH] OR &#x201c;physical therapy&#x201d; OR &#x201c;nutrition&#x201d;) AND (&#x201c;postoperative Complications&#x201d; [MeSH] OR &#x201c;morbidity&#x201d; OR &#x201c;mortality&#x201d; OR &#x201c;recovery&#x201d;) AND (randomized controlled trial[pt] OR &#x201c;randomized controlled trials as Topic&#x201d; [MeSH])</td>
</tr>
</tbody>
</table>
</table-wrap>
</sec>
<sec id="s2-4">
<title>Data extraction</title>
<p>The agreed-upon method was to extract and organize the data into Excel (Office 365, Microsoft, Redmond, WA, United States) spreadsheets for analysis. The following datatypes were extracted: descriptive data for the trials (author, year, type, and number of elements), patients demographics (age, sex, and performance), tumor related data (stage, location), and data related to the therapy received (neoadjuvant regimen, surgical procedure). In addition to this the comparative data on the occurrence of postoperative mortality, clinical or surgical complications, and performance status were also extracted.</p>
</sec>
<sec id="s2-5">
<title>Statistical analysis</title>
<p>The meta-analytic calculations were performed using the STATA statistical software package (StataCorp. 2017. Stata Statistical Software: Release 15. College Station, TX: StataCorp LLC). The working group of the Cochrane Collaborations recommendations was used during the data synthesis. From raw data, the pooled odds ratios (RRs) with 95% confidence intervals (CIs) were calculated for dichotomous variables. In the case of continuous variables, weighted mean differences (WMD) were calculated with 95% confidence intervals. As part of the analysis the random effect model was used with the estimation of DerSimonian and Laird, and the results were displayed on a forest plot. To assess heterogeneity, the Cochrane&#x2019;s Q and the I2 statistics were used. Statistical significance was achieved in the case of P &#x3c; 0.05. To account for studies with zero events in one or both arms, a continuity correction of 0.5 was added to each cell of the 2 &#xd7; 2 table to allow for the calculation of the risk ratio and its variance. Analysis was performed using the random-effects model (DerSimonian and Laird) where significant heterogeneity was observed (I<sup>2</sup> &#x3e; 50%), and the common effect model was applied in cases of low heterogeneity.</p>
<p>Sensitivity analyses were performed using the &#x2018;leave-one-out&#x2019; method to assess the robustness of our findings and to identify if any single study disproportionately influenced the overall effect size or the heterogeneity.</p>
<p>Trial sequential analysis was performed to assess the necessary number of cases to obtain conclusive evidence in each outcome using the trial sequential analysis tool from Copenhagen Trial Unit (Centre for Clinical Intervention Research, Denmark) [<xref ref-type="bibr" rid="B11">11</xref>].</p>
</sec>
<sec id="s2-6">
<title>Risk of bias and certain evidence</title>
<p>Estimating the quality of our investigation, we performed analysis of the article using the Risk of Bias Tool 2 (RoB2) and GRADE approaches.</p>
</sec>
</sec>
<sec sec-type="results" id="s3">
<title>Results</title>
<p>During the search process 9,555 articles were identified in the four databases and 8,262 articles remained after removal of duplicates. The selection steps by title, abstract and full text, further narrowed down the number of articles to 1,141 and 57. Finally, after the selection steps, 10 RCTs were included. Cohen&#x2019;s Kappa was 0.61, which was a substantial agreement between the selection steps of the two authors.</p>
<sec id="s3-1">
<title>Characteristics of the studies</title>
<p>All the included international articles used the randomized controlled trial methodology.</p>
<p>For the sake of clarity, the included RCTs are summarized in a table (<xref ref-type="table" rid="T3">Table 3</xref>).</p>
<table-wrap id="T3" position="float">
<label>TABLE 3</label>
<caption>
<p>List of the selected randomized controlled trials used for the meta-analysis.</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="left">Author</th>
<th align="left">Title</th>
<th align="left">Year</th>
<th align="left">DOI</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="left">Guinan et al.</td>
<td align="left">Effect of preoperative inspiratory muscle training on physical functioning following esophagectomy</td>
<td align="left">2019</td>
<td align="left">10.1093/dote/doy091</td>
</tr>
<tr>
<td align="left">Valkenet et al.</td>
<td align="left">Multicentre randomized clinical trial of inspiratory muscle training versus usual care before surgery for oesophageal cancer</td>
<td align="left">2018</td>
<td align="left">10.1002/bjs.10803</td>
</tr>
<tr>
<td align="left">Zylstra et al.</td>
<td align="left">Exercise prehabilitation during neoadjuvant chemotherapy may enhance tumour regression in oesophageal cancer: results from a prospective non-randomised trial</td>
<td align="left">2022</td>
<td align="left">10.1136/bjsports-2021-104243</td>
</tr>
<tr>
<td align="left">Kong et al.</td>
<td align="left">Effect of perioperative oral nutritional supplementation in malnourished patients who undergo gastrectomy: A prospective randomized trial</td>
<td align="left">2018</td>
<td align="left">10.1016/j.surg.2018.05.017</td>
</tr>
<tr>
<td align="left">Liu et al.</td>
<td align="left">Safety, feasibility, and effect of an enhanced nutritional support pathway including extended preoperative and home enteral nutrition in patients undergoing enhanced recovery after esophagectomy: a pilot randomized clinical trial</td>
<td align="left">2020</td>
<td align="left">10.1093/dote/doz030</td>
</tr>
<tr>
<td align="left">Loughney et al.</td>
<td align="left">The effect of a pre- and post-operative exercise program versus standard care on physical activity and sedentary behavior of patients with esophageal and gastric cancer undergoing neoadjuvant treatment prior to surgery (the PERIOP-OG trial): a randomized controlled trial</td>
<td align="left">2024</td>
<td align="left">10.1093/dote/doae044</td>
</tr>
<tr>
<td align="left">Yamana et al.</td>
<td align="left">Randomized controlled study to evaluate the efficacy of a preoperative respiratory rehabilitation program to prevent postoperative pulmonary complications after esophagectomy</td>
<td align="left">2015</td>
<td align="left">10.1159/000434758</td>
</tr>
<tr>
<td align="left">Minnella et al.</td>
<td align="left">Effect of exercise and nutrition prehabilitation on functional capacity in esophagogastric cancer surgery: A randomized clinical trial</td>
<td align="left">2018</td>
<td align="left">10.1001/jamasurg.2018.1645</td>
</tr>
<tr>
<td align="left">Allen et al.</td>
<td align="left">Multimodal prehabilitation during neoadjuvant therapy prior to esophagogastric cancer resection: Effect on cardiopulmonary exercise test performance, muscle Mass and quality of Life-A pilot randomized clinical trial</td>
<td align="left">2021</td>
<td align="left">10.1245/s10434-021-11002-0</td>
</tr>
<tr>
<td align="left">Bausys et al.</td>
<td align="left">Effect of home-based prehabilitation on postoperative complications after surgery for gastric cancer: randomized clinical trial</td>
<td align="left">2023</td>
<td align="left">10.1093/bjs/znad312</td>
</tr>
</tbody>
</table>
</table-wrap>
<p>The RCTs involved in the study utilized prehabilitation as an interventional tool at various levels; these, along with the proportion of UGI surgeries and the possible application of ERAS protocol, are summarized in a combined table (<xref ref-type="table" rid="T1">Table 1</xref>).</p>
</sec>
<sec id="s3-2">
<title>Characteristics of the patients</title>
<p>The mean age was 63.9 &#xb1; 5.2 years in the prehabilitation group and 64.2 &#xb1; 4.8 years in the control group. The gender distribution was as follows: the prehabilitation group included a total of 122 women and 318 men, while the control group included 118 women and 320 men.</p>
</sec>
<sec id="s3-3">
<title>Characteristics of the tumor and pathological approach</title>
<p>Out of the 10 RCTs, 7 addressed tumor staging. Among these, 6 studies (total number of patients: 523; prehabilitation group: 295; control group: 228) analyzed T(0-)1&#x2013;4 and N0&#x2013;3 staging, while one study used the AJCC pathological tumor staging system. Only one study reported T0 stage, including 13 patients in the prehabilitation group and 12 patients in the control group. In the prehabilitation group, T1 stage was recorded in 54 patients, T2 in 53, T3 in 140, and T4 in 27 patients. In the control group, T1 stage was observed in 52 patients, T2 in 40, T3 in 150, and T4 in 27 patients. The AJCC pathological tumor staging system was applied in one study involving a total of 51 patients (prehabilitation group: 26; control group: 25). In the prehabilitation group, 6 patients were classified as stage I, 0 as stage II, and 18 as stage III. In the control group, 5 patients were stage I, 2 were stage II, and 18 were stage III.</p>
</sec>
<sec id="s3-4">
<title>Characteristics of the surgical procedure</title>
<p>The analysis of surgical interventions was challenging due to discrepancies in nomenclature. Following our extensive research on the subject, we found the following: open surgical procedures were examined in four studies, involving a total of 133 patients in the prehabilitation group and 132 patients in the control group. Two articles focused on laparoscopic techniques, with 40 patients undergoing the procedure in each group. VATS (video-assisted thoracoscopic surgery) was reported in two studies, involving 68 patients in the prehabilitation group and 67 in the control group. RATS (robot-assisted thoracic surgery) was performed in 28 patients from the prehabilitation group and 21 from the control group. The transhiatal approach was mentioned in four articles, with 22 patients in the prehabilitation group and 32 in the control group. Transthoracic procedures were described in three studies, including 145 patients who underwent prehabilitation and 141 in the control group. Esophagectomy was reported in two articles, with 21 procedures in the prehabilitation group and 26 in the control group. Partial gastrectomy was described in three studies, with 86 procedures performed in each group. Total gastrectomy was addressed in five articles, involving 45 patients in the prehabilitation group and 44 in the control group. Minimally invasive surgical approaches were discussed in five articles, including a total of 155 patients in the prehabilitation group and 137 in the control group.</p>
</sec>
<sec id="s3-5">
<title>Mortality</title>
<p>&#x201c;In the included trials, no significant differences were found between the two groups in hospital mortality (p &#x3d; 0.4094; RR: 1.17; 95% CI: 0.4&#x2013;3.43; n &#x3d; 390), 30-day mortality (0 events among 144 patients), or 90-day mortality (p &#x3d; 0.7582; RR: 3.99; 95% CI: 0.47&#x2013;34.04; n &#x3d; 144) (<xref ref-type="fig" rid="F2">Figures 2</xref>, <xref ref-type="fig" rid="F3">3</xref>). Given that there were no cases of 30-day mortality, this parameter has been omitted from the figure.</p>
<fig id="F2" position="float">
<label>FIGURE 2</label>
<caption>
<p>Comparison of mortality within 90 days.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g002.tif">
<alt-text content-type="machine-generated">Forest plot displaying risk ratios from three studies comparing experimental and control groups for a specific outcome. Individual and pooled risk ratios with 95% confidence intervals are shown, with no observed heterogeneity and study weights indicated.</alt-text>
</graphic>
</fig>
<fig id="F3" position="float">
<label>FIGURE 3</label>
<caption>
<p>Comparison of in-hospital mortality rates.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g003.tif">
<alt-text content-type="machine-generated">Forest plot summarizing four studies comparing experimental and control groups, displaying risk ratios with confidence intervals, weights, and total events. Pooled results show risk ratios of 1.17 (common) and 1.30 (random effects) with low heterogeneity.</alt-text>
</graphic>
</fig>
</sec>
<sec id="s3-6">
<title>Complication severity analysis</title>
<p>In terms of morbidity, due to the increasingly widespread use of the Clavien-Dindo classification system, we found fewer specific data on the occurrence of individual complications. As a result, we could only identify the wound infection and chyle leak groups, without naming additional categories.</p>
<p>However, the Clavien-Dindo classification establishes a standardized and unified criterion system, which allows for the harmonization of morbidity rates across international studies. The Clavien-Dindo classification defined five complication grades. Grade I includes deviation from normal postoperative course without pharmacological treatment or intervention. Grade II involved complications requiring pharmacological treatment. Grade III referred to complications requiring surgical, endoscopic or radiological intervention with Grade IIIa as a subcategory where intervention happens without anesthesia and Grade IIIb where intervention happens under general anesthesia. Grade IV encompasses cases where life-threatening complications require ICU management, with Grade IVa as a subcategory where a single organ is dysfunctional while Grade IVb includes cases of multi-organ failure. Lastly, Grade V includes cases which resulted in the death of the patients. The grades described here will be used later in the evaluation of the results below [<xref ref-type="bibr" rid="B12">12</xref>].</p>
<p>Among the 523 patients analyzed for minor complications (Clavien&#x2013;Dindo I&#x2013;II), a reduction was observed in the prehabilitation group (RR: 0.74; 95% CI: 0.58&#x2013;0.96; p &#x3e; 0.05). However, considering the heterogeneity and applying a random-effects model, this difference reached only a statistical trend rather than robust significance. Regarding severe complications (Clavien&#x2013;Dindo Grade III), the analysis of 523 patients showed low heterogeneity, justifying the use of a common effects model. Under this model, prehabilitation was associated with a significant reduction in Grade III complications (RR: 0.62; 95% CI: 0.39&#x2013;0.99; p &#x3c; 0.05) (<xref ref-type="fig" rid="F4">Figures 4</xref>&#x2013;<xref ref-type="fig" rid="F6">6</xref>).</p>
<fig id="F4" position="float">
<label>FIGURE 4</label>
<caption>
<p>Postoperative morbidity: Clavien-Dindo grade I-II complications.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g004.tif">
<alt-text content-type="machine-generated">Forest plot showing risk ratios and confidence intervals for seven studies comparing experimental and control event rates, with common effects model RR 0.74 (95% CI 0.58-0.96) and random effects model RR 0.77 (95% CI 0.45-1.31). Heterogeneity reported with I squared equals 58.7 percent, tau squared equals 0.2869, and p equals 0.0241. Each study is individually listed with calculated effect size, weight, and event counts.</alt-text>
</graphic>
</fig>
<fig id="F5" position="float">
<label>FIGURE 5</label>
<caption>
<p>Postoperative morbidity: Clavien-Dindo grade III complications.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g005.tif">
<alt-text content-type="machine-generated">Forest plot showing risk ratios with 95 percent confidence intervals for seven studies comparing experimental and control event rates. Diamond markers summarize common and random effects models. Heterogeneity statistics are provided below the plot.</alt-text>
</graphic>
</fig>
<fig id="F6" position="float">
<label>FIGURE 6</label>
<caption>
<p>Postoperative morbidity: Clavien-Dindo grade IV complications.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g006.tif">
<alt-text content-type="machine-generated">Forest plot summarizing a meta-analysis of six studies, reporting risk ratios and ninety-five percent confidence intervals for each. Studies are Zlystra et al. 2022, Liu et al. 2020, Loughney et al. 2024, Minnella et al. 2018, Bausys et al. 2023, and Yamana 2015. Diamonds show combined effect sizes for common and random effects models with respective pooled risk ratios of one point sixty-one and one point sixty-four. No observed heterogeneity is indicated with I-squared zero percent and p-value zero point eight two two.</alt-text>
</graphic>
</fig>
</sec>
<sec id="s3-7">
<title>Surgical complications</title>
<p>No significant differences were detected in postoperative surgical complications, with bleeding assessed in 283 patients (p &#x3d; 0.273; RR: 1.38; 95% CI: 0.45&#x2013;4.28), wound infection in 541 patients (p &#x3d; 0.206; RR: 1.14; 95% CI: 0.60&#x2013;2.14), and chyle leakage in 425 patients (p &#x3d; 0.44; RR: 1.40; 95% CI: 0.72&#x2013;2.73) (<xref ref-type="fig" rid="F7">Figures 7</xref>, <xref ref-type="fig" rid="F8">8</xref>).</p>
<fig id="F7" position="float">
<label>FIGURE 7</label>
<caption>
<p>Incidence of wound infection.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g007.tif">
<alt-text content-type="machine-generated">Forest plot showing risk ratios and confidence intervals for four studies comparing experimental and control groups, with pooled estimates from common and random effect models. Heterogeneity statistics are included at the bottom.</alt-text>
</graphic>
</fig>
<fig id="F8" position="float">
<label>FIGURE 8</label>
<caption>
<p>Incidence of postoperative chyle leak.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g008.tif">
<alt-text content-type="machine-generated">Forest plot comparing risk ratios from three studies of an intervention, displaying point estimates with confidence intervals. Combined risk ratios are 1.40 and 1.30 for fixed and random effects models, with no significant heterogeneity reported.</alt-text>
</graphic>
</fig>
<p>It is crucial to highlight anastomotic leakage, as it remains the most dreaded complication following upper gastrointestinal (UGI) surgery. No significant differences were detected in postoperative surgical complications regarding anastomotic leakage, which was assessed in 567 patients (p &#x3d; 0.85; RR: 0.95; 95% CI: 0.56&#x2013;1.62) (<xref ref-type="fig" rid="F9">Figure 9</xref>).</p>
<fig id="F9" position="float">
<label>FIGURE 9</label>
<caption>
<p>Incidence of anastomotic leakage.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g009.tif">
<alt-text content-type="machine-generated">Forest plot summarizing five studies comparing experimental and control groups, displaying risk ratios and confidence intervals. The overall random effects and common effect model risk ratio is 0.95 with confidence interval 0.56 to 1.62, and heterogeneity measures show I squared equals zero percent with p-value 0.85.</alt-text>
</graphic>
</fig>
</sec>
<sec id="s3-8">
<title>Other outcomes</title>
<p>No significant differences were observed in cardiovascular complications among 543 evaluated patients (p &#x3d; 0.77; RR: 0.80; 95% CI: 0.51&#x2013;1.25) or in the risk of readmission among 398 patients (p &#x3d; 0.66; RR: 0.58; 95% CI: 0.29&#x2013;1.18) (<xref ref-type="fig" rid="F10">Figure 10</xref>).</p>
<fig id="F10" position="float">
<label>FIGURE 10</label>
<caption>
<p>Rates of hospital readmission within the follow-up period.</p>
</caption>
<graphic xlink:href="pore-32-1612328-g010.tif">
<alt-text content-type="machine-generated">Forest plot comparing risk ratios and confidence intervals for five studies, showing experimental and control event rates and total sample sizes. The summary risk ratio is 0.60 with a 95 percent confidence interval from 0.29 to 1.25, indicating no significant effect. Study weights and heterogeneity statistics are shown.</alt-text>
</graphic>
</fig>
<p>The main mortality and morbidity data are summarized in <xref ref-type="table" rid="T4">Table 4</xref>.</p>
<table-wrap id="T4" position="float">
<label>TABLE 4</label>
<caption>
<p>GRADE approach.</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="left">Outcome</th>
<th align="left">No. of participants</th>
<th align="left">Relative effect (RR, 95% CI)</th>
<th align="left">p-value</th>
<th align="left">Certainty of evidence</th>
<th align="left">Interpretation</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="left">30- day mortality</td>
<td align="left">144</td>
<td align="left">-</td>
<td align="left">-</td>
<td align="left">Very low</td>
<td align="left">No difference detected</td>
</tr>
<tr>
<td align="left">90-day mortality</td>
<td align="left">144</td>
<td align="left">RR: 3.99 (0.47&#x2013;34.04)</td>
<td align="left">0.7582</td>
<td align="left">Very low</td>
<td align="left">No difference detected</td>
</tr>
<tr>
<td align="left">In-hospital mortality</td>
<td align="left">390</td>
<td align="left">RR: 1.17 (0.4&#x2013;3.43)</td>
<td align="left">0.4094</td>
<td align="left">Very low</td>
<td align="left">No difference detected</td>
</tr>
<tr>
<td align="left">Minor complications (CD I&#x2013;II)</td>
<td align="left">523</td>
<td align="left">RR: 0.74 (0.58&#x2013;0.96)</td>
<td align="left">&#x3e;0.05 v</td>
<td align="left">Low</td>
<td align="left">Non-significant trend toward reduction</td>
</tr>
<tr>
<td align="left">Severe complications (CD-III)</td>
<td align="left">523</td>
<td align="left">RR: 0.62 (0.39&#x2013;0.99)</td>
<td align="left">&#x3c;0.05</td>
<td align="left">Moderate</td>
<td align="left">Significantly lower in prehab group (common effects model)</td>
</tr>
<tr>
<td align="left">Life-threatening complications (CD-IV)</td>
<td align="left">396</td>
<td align="left">RR: 1.61 (0.51&#x2013;5.12)</td>
<td align="left">0.82</td>
<td align="left">Very low</td>
<td align="left">No significant difference</td>
</tr>
<tr>
<td align="left">Bleeding</td>
<td align="left">283</td>
<td align="left">RR: 1.38 (0.45&#x2013;4.28)</td>
<td align="left">0.273</td>
<td align="left">Very low</td>
<td align="left">No significant difference</td>
</tr>
<tr>
<td align="left">Wound infection</td>
<td align="left">541</td>
<td align="left">RR: 1.14 (0.60&#x2013;2.14)</td>
<td align="left">0.206</td>
<td align="left">Very low</td>
<td align="left">No significant difference</td>
</tr>
<tr>
<td align="left">Chyle leak</td>
<td align="left">425</td>
<td align="left">RR: 1.40 (0.72&#x2013;2.73)</td>
<td align="left">0.44</td>
<td align="left">Very low</td>
<td align="left">No significant difference</td>
</tr>
<tr>
<td align="left">Cardiovascular complications</td>
<td align="left">543</td>
<td align="left">RR: 0.80 (0.51&#x2013;1.25)</td>
<td align="left">0.77</td>
<td align="left">Very low</td>
<td align="left">No significant difference</td>
</tr>
<tr>
<td align="left">Readmission</td>
<td align="left">398</td>
<td align="left">RR: 0.58 (0.29&#x2013;1.18)</td>
<td align="left">0.66</td>
<td align="left">Very low</td>
<td align="left">No significant difference</td>
</tr>
</tbody>
</table>
</table-wrap>
</sec>
</sec>
<sec sec-type="discussion" id="s4">
<title>Discussion</title>
<p>While prehabilitation constitutes a core element of the ERAS pathway, <xref ref-type="table" rid="T1">Table 1</xref> demonstrates that it is frequently implemented independently of formal ERAS protocols. Unfortunately, the ERAS protocol is still not fully accepted for patients with upper gastrointestinal tumors. As a result, not only is the intraoperative and postoperative protocol not followed&#x2014;such as early feeding, which has increasing evidence supporting its safety&#x2014;but prehabilitation is also not implemented in the preoperative period. This is particularly concerning as these patients are often in poor general condition, and prehabilitation could help prepare them physically, nutritionally, and psychologically for surgery. Our goal with this meta-analysis is to highlight the importance and legitimacy of prehabilitation protocol for UGI tumor patients.</p>
<p>Our findings are further supported by a recent 2025 meta-analysis, which examined both randomized clinical trials and cohort studies in patients with upper gastrointestinal cancer. In line with our results, this study demonstrated that prehabilitation significantly promotes postoperative recovery, specifically by shortening the length of hospital stay and improving functional capacity, such as the 6-min walk distance. Notably, it also highlighted a significant reduction in the occurrence of postoperative pneumonia (RR 0.71). Consistent with our analysis, they found no significant differences in major outcomes such as anastomotic leakage, in-hospital mortality, or overall postoperative complications, reinforcing the conclusion that prehabilitation primarily impacts the speed of recovery and the reduction of minor or specific pulmonary events rather than major surgical failures [<xref ref-type="bibr" rid="B13">13</xref>].</p>
<p>The present meta-analysis included 10 RCTs, analyzing data from a total of 878 patients who were divided into two groups. The first group consisted of patients who underwent prehabilitation while the second comprised those who were part of the control group.</p>
<p>The complications we examined are best described by the Clavien-Dindo classification [<xref ref-type="bibr" rid="B12">12</xref>].</p>
<p>The lower-grade complications are particularly relevant from a quality-of-life perspective, as they often affect patient comfort and recovery. Key examples include atelectasis, pneumonia, wound infections, and infectious diarrhea-conditions that, while not life-threatening, can significantly impact the patient&#x2019;s wellbeing and prolong recovery time.</p>
<p>Our study observed a notable reduction in minor complications for patients in the prehabilitation group, although this did not reach full statistical significance across all models, suggesting a positive trend toward improved recovery.Our aim was to shed light on the necessity of prehabilitation in patients with upper gastrointestinal tumors.</p>
<p>Examining minor postoperative complications, it was noted that similar findings were reported by Bausys et al. in their study, which included 61 patients in the intervention group and 61 in the control group. Their research analyzed complications such as wound infections, pulmonary complications, anastomotic insufficiency, anaemia requiring blood transfusion, intra-abdominal abscesses, pancreatic complications, postoperative bleeding, cardiovascular and neurological complications, duodenal stump leakage, anastomosis stenosis, and urinary tract infections. An analysis of complication severity revealed that minor complications (Clavien&#x2013;Dindo grades I&#x2013;II) occurred significantly less frequently in the prehabilitation group (6.8% compared to 42.4%, P &#x3d; 0.001; RR 0.16, 0.05&#x2013;0.43). While initial global assessments suggested no difference, a focused analysis of Grade III complications&#x2014;which require surgical, endoscopic, or radiological intervention&#x2014;revealed a significant reduction in the prehabilitation group when using a common effects model, consistent with the low heterogeneity observed for this outcome. (16.9% versus 18.6%, P &#x3d; 0.810; RR 0.90, 0.41&#x2013;1.97) [<xref ref-type="bibr" rid="B14">14</xref>].</p>
<p>From a mortality perspective, which underscores the importance of prehabilitation for patients in a weakened general condition before surgery, our study found that there was no significant difference between the two groups.</p>
<p>Another study by Allen et al., examined 54 patients (prehabilitation group: n &#x3d; 26; control group: n &#x3d; 28) and reported similar findings to ours. According to their results, no deaths occurred within the first 60 days after surgery. In the prehabilitation group, two patients passed away within 90 days of surgical resection, at 66 and 71 days respectively, both due to disease recurrence. There was no significant difference in 3-year cancer-related mortality between the groups [11 patients (50%) in the prehabilitation group vs. 10 patients (43%) in the control group; p &#x3d; 0.343] [<xref ref-type="bibr" rid="B15">15</xref>].</p>
<p>The study of prehabilitation has some limitations. The concept of prehabilitation has many interpretations, encompassing nutritional, physical, and mental prehabilitation. Most studies focused on nutritional and/or physical prehabilitation, while mental prehabilitation received little attention. The randomized controlled trials are not uniform in their outcomes, as demonstrated by the diversity in our meta-analysis. Regarding sample size, the international literature on this topic has not yet shown sufficient interest in this area of medicine, resulting in relatively small patient numbers. Further randomized controlled trials are needed.</p>
<p>In conclusion, this meta-analysis indicates that prehabilitation in patients undergoing surgery for upper gastrointestinal tumors shows a positive trend toward reducing minor postoperative complications (Clavien&#x2013;Dindo grade I&#x2013;II), and furthermore, it results in a statistically significant reduction in severe complications (Clavien&#x2013;Dindo Grade III), although the impact on life-threatening complications (Grade IV) remains non-significant. No significant differences were found in cardiovascular complications or hospital readmission rates either.</p>
<p>These findings support the clinical safety and potential benefit of implementing prehabilitation programs in this patient population.</p>
<p>However, the overall certainty of evidence remains low to very low for most outcomes, highlighting the need for larger, high-quality randomized controlled trials, especially focusing on the role of mental and multimodal prehabilitation, to strengthen the evidence base and standardize clinical protocols in surgical oncology.</p>
</sec>
</body>
<back>
<sec sec-type="data-availability" id="s5">
<title>Data availability statement</title>
<p>The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.</p>
</sec>
<sec sec-type="author-contributions" id="s6">
<title>Author contributions</title>
<p>CP conducted examinations, wrote the manuscript, and collected data. AC conducted and collected data. DK performing statistical work. LS collected data. AV conducted the investigation. AP developing the hypothesis, conducted the investigation. All authors contributed to the article and approved the submitted version.</p>
</sec>
<ack>
<title>Acknowledgements</title>
<p>We extend our sincere gratitude to the dedicated staff and colleagues of the Department of Surgery of the University of P&#xe9;cs Clinical Centre, for their continuous support and assistance throughout the preparation and execution of this meta-analysis. Their clinical insights and collegial environment were invaluable to this research. Special thanks are also directed to D&#xe1;niel Kehl for his essential contribution in performing the statistical analyses and data interpretation, which formed a critical component of this systematic review.</p>
</ack>
<sec sec-type="COI-statement" id="s8">
<title>Conflict of interest</title>
<p>The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec sec-type="ai-statement" id="s9">
<title>Generative AI statement</title>
<p>The author(s) declared that generative AI was not used in the creation of this manuscript.</p>
<p>Any alternative text (alt text) provided alongside figures in this article has been generated by Frontiers with the support of artificial intelligence and reasonable efforts have been made to ensure accuracy, including review by the authors wherever possible. If you identify any issues, please contact us.</p>
</sec>
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