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The human papilloma virus (HPV) high-risk variants (HPV-HR) such as HPV16 and HPV18 are responsible for most HPV related cancers, including anogenital and head and neck cancers. Here, we present two patients with HPV-HR-associated gynecological malignancies who, after failing radiation therapy, were treated with experimental salvage immunotherapy regimen resulting in complete, durable responses in both patients. Each patient was diagnosed with recurrent, radiation-refractory, HPV-HR positive, squamous cell carcinoma of the lower genital tract. Patient A was a 90-year-old, African American, with metastatic vulvar cancer to the right inguinal-femoral triangle and pulmonary metastases. Patient B was a 41-year-old, Caucasian, with a central-recurrence of cervix cancer. Each patient received at least two intratumoral quadrivalent HPV-L1 vaccine (Gardasil™) injections and daily topical TLR-7 agonist (imiquimod) to the tumor surface 2 weeks apart. This combination of intratumoral vaccinations and topical TLR-7 agonist produced unexpected complete resolution of disease in both patients. The importance of radiation therapy, despite being considered a treatment failure by current definitions, cannot be understated. Radiation therapy appears to have offered a therapeutic immune advantage by modifying the tumor microenvironment. This immune protocol has potential to help patients with advanced HPV-HR-related malignancies previously considered incurable.
The human papilloma viruses (HPV) are responsible for ∼30% of viral-induced cancers. There are at least fourteen known oncogenic or high-risk HPV (HPV-HR) types. Prophylactic HPV vaccines have proven effective in preventing benign and malignant manifestations of this virus in both men and women. Unfortunately, these vaccines require at least 10–20 years “lead-in” time before showing an epidemiological-effect in cancer prevention. Despite the proven successes of these vaccines, society has neither embraced the significance nor adequately utilized this medical advancement. In addition, immunotherapies to effectively treat HPV-HR cancers have been elusive. We present two patients with HPV-HR positive gynecological malignancies who recurred following radiation therapy. Both patients were desperate and facing dismal prognoses. We describe the “off-label” use of two FDA-approved immune drugs consisting of intratumoral vaccinations of quadrivalent HPV-L1 vaccine (Gardasil™) and daily application of topical imiquimod resulting complete resolution of radiation refractory disease in both patients.
These are the only two patients treated with this combination of intra-tumoral vaccinations of quadrivalent HPV vaccine and topical imiquimod after presenting with radiation refractory disease. Each female patient had personal and logistical issues limiting travel for inclusion into regional/national research studies. Both patients requested alternative treatment options that could be administered during their current treatment choices. Following Bioethics Committee review and approval, of each patient was consented and received the immune regimen of intratumoral injections of quadrivalent HPV-L1 vaccine (Gardasil™) and topical imiquimod (
Immunotherapy protocol for patient A and patient B.
Immunotherapy protocol | Details |
---|---|
Quadrivalent HPV-L1 Antigen Vaccine (Gardasil™) | Volume-0.5 ml |
L1 antigens: 120 mcg; HPV 16 = 20 mcg; HPV 18 = 40 mcg; HPV 6 = 20 mcg; and HPV 11 = 40 mcg | |
Adjuvant used | Aluminum hydroxyphosphate = 225 mcg |
Vaccination cycle | Intratumoral injections followed by application of topical imiquimod for fourteen nights |
Number of planned cycles | 3, if needed |
Quadrivalent vaccine used per cycle | 0.25 ml, or 60 mcg, of original vaccine volume |
Imiquimod concentration used | Patient A applied one 250 mcg dose of 5% imiquimod (3M™) |
Patient B applied a compounded 0.2% imiquimod vaginal suppository (compounded locally) | |
Treatment: cycle #1 | Intratumoral vaccination of Patient A and B using 0.25 ml quadrivalent vaccine diluted with 2.75 ml saline (total volume 3 ml) injected evenly throughout entire recurrent tumor |
Day 1: Imiquimod therapy applied immediately after intratumoral injection again that night | |
Day 2–14: Imiquimod applied topically to surface of tumor by patient before bed | |
Treatment Cycle #2: Day #15 | Both patients received the same treatment as cycle #1. In addition, each patient received a subcutaneous injection in the right shoulder as a “booster.” This was a subcutaneous injection and not IM. Subcutaneous injection offers immune stimulation of Langerhan cells which are also present in skin and mucosal/submucosal areas in which these tumors arise. We considered this offered a “prime-boost” effect. This was the only vaccination given that was not intratumoral |
Patient B received cycle #2 8 days before planned exenterative surgery | |
Treatment Cycle #3 | Patient A missed her appointment 2 weeks following her second cycle |
Eleven weeks after cycle #2, she received the last intratumoral injection into a 2 cm3 tumor as shown in |
|
Patient B received only 2 cycles |
Demographic comparison between patients A and B.
Patient A | Patient B | |
---|---|---|
Age | 90 years | 41 years |
Ethnicity | African-American | Caucasian |
HPV + malignancy site | Vulva | Cervix |
Grade of tumor | Grade I, squamous cell carcinoma | Grade 2, squamous cell carcinoma |
Stage at initial diagnosis | Stage 2 vulvar cancer | Stage 3B cervical cancer |
Initial therapy | Radical hemi-vulvectomy with bilateral sentinal lymph node biopsies | Cisplatin-based chemo-radiation plus two cesium low-dose rate tandem and ovoids |
Recurrent cancer interval and location | 3 years to right groin and bilateral pulmonary metastasis | 3 weeks after second cesium implant with 3–4 cm tumor on cervix |
Initial treatment of recurrence | Palliative fractionated external radiation (120 cGy to right groin/day for 10 fractions = 1200 cGy) | Planned pelvic exenteration |
Intratumoral therapy started | 7 days after completing radiation | 4 weeks after second cesium implant |
Patient A was a 90-year-old African-American female with recurrent, HPV-HR positive, squamous cell carcinoma (grade 1) of the vulva with metastatic disease to the right inguinal-femoral triangle (11 × 11 cm tumor) and bilateral pulmonary metastasis. Previously, this patient presented with a 4 cm peri-clitoral, grade 1, squamous cell carcinoma treated by radical hemi-vulvectomy and bilateral inguinal sentinel node biopsies. The vulvectomy specimen demonstrated no lymph-vascular space invasion and the specimen’s margins were clear. Bilateral inguinal sentinel lymph nodes, consisting of two nodes on the left and three nodes from right, were negative for malignant cells. No further therapy was required, and the patient never returned for follow-up until presenting 3 years later with 11 × 11 cm squamous cell carcinoma of right groin causing a right lower extremity deep vein thrombosis. Chest x-ray revealed a “snow storm” appearance from bilateral pulmonary metastasis (
Following the first 2-week cycle of immune therapy, the ulcerated, granular tumor surface was now flat and smooth, the margins of the ulcer were initially irregular and asymmetric were now well-defined and symmetric. The odor resolved and a yellowish, purulent, exudate was present (
Tumor images of patients A and B.
The patient was a 41-year-old Caucasian female, diagnosed with stage IIIB, HPV-HR positive, moderately differentiated squamous cell carcinoma of the cervix (
There are no curative therapies to treat radiation refractory cervix cancer unless an isolated central cervical recurrence is present without evidence of metastatic disease. Patient B met the criteria for pelvic exenterative surgery. The experimental immune therapy was started while preparing for surgery. The first cycle of intratumoral injections of HPV-L1 vaccine was given followed by intravaginal 0.2% imiquimod suppositories every night until the second intratumoral injection 14 days later. This patient’s tumor produced the same characteristics as patient A’s tumor at 14 days. The surface of Patient B’s cervical cancer was no longer granular, irregular, and friable as seen initially but had a smooth, symmetric tumor surface. As observed with patient A’s groin tumor 2 weeks after the first injection, Patient B’s tumor decreased less than 25% following the first cycle. Surgery was scheduled 8 days after the second injection. On the day of surgery, examination under anesthesia demonstrated complete resolution of her radiation refractory cervix cancer. Frozen sections on two cervical biopsies were negative for persistent cancer. Therefore, in light of these new findings, the planned pelvic exenteration was aborted and post-radiation, radical hysterectomy with upper vaginectomy, bilateral salpingo-oopherctomy and pelvic and para-aortic lymphadenectomy was performed (
This paper emphasizes the use of sequential, targeted vaccinations of the FDA-approved, quadrivalent, HPV-L1 antigens vaccine injected throughout the previously irradiated tumor. HPV-L1 peptide has been found to produce an effective anti-tumor response [
There are several studies describing vaccine-based immunotherapies to treat malignant tumors. A complete review of therapeutic vaccines can be found elsewhere [
Radiation therapy is vital in changing the tumor’s well-established, immunosuppressive microenvironment [
Proposed mechanism of synergistic anti-tumor activity of radiation and combination immunotherapy.
Radiation therapy, when use as a single treatment modality, has not consistently produced therapeutic responses outside of the radiated field known as “abscopal effects” without the addition of adjuvant immunotherapies [
From a safety standpoint, this immune protocol produced no discernible toxicities in either patient. Our observations suggest that combination of imiquimod and quadrivalent HPV vaccine is likely less toxic and more tolerable than systemic cytotoxic chemotherapies. Most immune therapies do not result in cross-resistance with conventional therapies [
We describe two female patients presenting with radiation-refractory, HPV-associated, squamous cell carcinomas of the lower genital tract facing death, patient A, or pelvic exenteration, patient B. Each patient was treated with an experimental therapy consisting of intratumoral injections of the preventative, quadrivalent HPV-L1 vaccine and topical application of imiquimod within 4 weeks following radiation therapy. Each patient demonstrated complete resolution of the treated tumor in addition to patient A’s clinical abscopal response of her pulmonary metastases allowing her to live an additional 9 months 2 weeks after starting this combination immune therapy. Currently, Patient B is alive with no evidence of disease 8 years following the modification of her surgery to a less radical operation due to resolution of her central recurrence 8 days after her second cycle of intratumoral therapy. We believe radiation therapy followed by intratumoral vaccinations and topical TLR-7 agonist resulted in a “prime-boost” response facilitating an appropriate cytotoxic antitumor response. If this combination of cancer therapies can be validated in appropriate clinical trials; this therapy could offer an urgent and unmet need for patients with treatment-refractory, HPV-related malignancies. Additionally, both medications in this report are FDA-approved for other conditions and have established safety profiles. The combination of radiation therapy followed by sequential intratumoral vaccinations and topical imiquimod could conveniently translate to the clinic setting and offers potential cost savings.
The original contributions presented in the study are included in the article/
The studies involving human participants were reviewed and approved by Institutional Ethics Committee. The patients/participants provided their written informed consent to participate in this study.
MR designed the therapy, analyzed the outcomes, and wrote the manuscript. SJ and KP participated in the discussion and edited the manuscript.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
The Supplementary Material for this article can be found online at: