[Treatment of vulvar intra-epithelial neoplasias with Imiquimod]

Vulvar High-Grade Squamous Intraepithelial Lesions Treated with Imiquimod: Can Persistence of Human Papillomavirus Predict Recurrence?

Simple Summary

Vulvar high-grade intraepithelial lesion (vulvar HSIL) is a premalignant vulvar condition that requires intervention, usually surgery. It recurs frequently, and its treatment involves repeated disfiguring surgeries. Vulvar HSIL is associated with human papillomavirus. Imiquimod is a medical treatment option currently attracting attention because vulvar high-grade intraepithelial neoplasia is frequent in young women with multiple vulvar lesions. Few studies have evaluated the long-term effects of the response to imiquimod and the association of human papillomavirus with response and recurrence. We describe a retrospective (with cases already treated) study designed to determine the long-term response to imiquimod in patients with vulvar HSIL, and also to analyze the role of human papillomavirus (HPV), and different HPV types, in the persistence or recurrence of vulvar HSIL after imiquimod treatment.

Abstract

Objectives: Vulvar high-grade squamous intraepithelial lesion (vulvar HSIL) or vulvar intraepithelial neoplasia (VIN) is a premalignant condition that can progress to carcinoma. Imiquimod is a topical drug with high effectiveness and low morbidity. We aimed (1) to assess the long-term response to imiquimod in a cohort of patients with vulvar HSIL and (2) and to analyze the role of HPV determined in pre- and post-imiquimod treatment biopsies in the persistence or recurrence of vulvar HSIL. Design: Retrospective study between 2011 and 2022. Setting: Referrals from the primary care area of Baix Llobregat treated in the gynecology department of a university hospital in Barcelona, Spain. Population: 20 women with vulvar HSIL treated with imiquimod. Methods: The inclusion criteria were vulvar HSIL, vulvar HPV determination by pre- and post-treatment biopsy, acceptance of medical treatment, at least one follow-up and 4 weeks of treatment. Main outcome measures: Histological diagnosis of vulvar HSIL with pre- and post-imiquimod HPV determination. Response to treatment (complete, partial, no response, recurrence). Results: After imiquimod, 10 (50%) and 6 (30%) cases had complete and partial responses, respectively. Another 4 cases (20%) did not respond. Before treatment, 19 (95%) cases were positive for vulvar HPV (16 cases had HPV type 16). After treatment, 10 cases (50%) were positive for HPV (8 cases with HPV type 16): 2 cases (20%) with a complete response, 5 cases (83.3%) with a partial response and 3 cases (75%) with no response. Eight of the 10 HPV-negative cases (80%) post-treatment showed a complete response. HPV type 16 was present in 16 cases (84.2%) pre-treatment and in 8 cases (80%) post-treatment. Ten patients underwent additional treatments following a partial response, no response or recurrence. The 2 HIV and 3 immunosuppressed patients treated with imiquimod showed a partial response and required additional treatment. All these patients were HPV-positive pre- and post-treatment (100%). Response to imiquimod was associated with post-treatment vulvar HPV positivity (p = 0.03). The median time to a complete response in HPV-negative cases was 4.7 months versus 11.5 months in HPV-positive cases post-imiquimod treatment. Recurrence of vulvar HSIL was observed in 7 patients (35%), with a median time to recurrence of 19.7 months (range 3.2–32.7). Recurrence was experienced in 10% of cases with a complete response, in 4/6 (66.6%) cases with a partial response, and in 2/4 (50%) women with no response. Four of the 7 recurrent cases (57%) were infected with HIV or immunosuppressed. Six (85%) of the recurrent cases were HPV-positive post-treatment (all were HPV type 16). Four (30.7%) of the non-recurrent cases were HPV-positive post-treatment with imiquimod (p = 0.05), two of which were HPV type 16 (50%). Conclusions: Imiquimod effectively treats vulvar HSIL. Cases with a complete response showed less HPV positivity post-treatment than partial or non-response cases. Recurrences were more frequent in those with a partial or no response to imiquimod, and in immunosuppressed patients. In recurrent cases, 85% were HPV-positive post-treatment, while 30.7% of non-recurrent cases were HPV-positive. HPV positivity in the post-treatment biopsy suggests the need for stricter follow-up of patients.

Surgical Treatment of Vulvar HSIL: Adjuvant HPV Vaccine Reduces Recurrent Disease

Data suggest that adjuvant human papillomavirus (HPV)-vaccination in women treated for cervical HPV diseases reduces recurrent disease. This study investigates adjuvant HPV-vaccination and the rate of recurrence in women undergoing surgery for vulvar high-grade squamous intraepithelial lesions (HSIL). From January 2013 to April 2020, we enrolled 149 women in a prospective case-control study. The control group (NV-group) was treated by standard surgery alone, while the study group received adjuvant vaccination soon after surgery (V-group). A follow-up was performed by vulvoscopy and HPV test. Statistical analysis was performed by Fisher's exact test. HSIL recurrence was observed in 24/76 (32%) patients in NV-group and in 8/42 patients (19%) of the vaccinated group. By analysing the recurrence rate related to the incident and reactivated latent HPV infection, we found a significant difference between (17/76) 22.3% in NV-group and (2/42) 4.8% in V-group (p = 0.01). A reduction of 78.5% in incident/reactivated HPV infections was demonstrated. Data results add to the current knowledge about the mechanism of post-surgical adjuvant HPV vaccination. Our prospective study is the first to document the vaccine clinical effectiveness in preventing "reactivation" of latent HPV infections. Quadrivalent HPV vaccine administered after the surgical treatment for vulvar HSIL appears to be useful in preventing recurrent disease.

Vulvar intraepithelial neoplasia: Classification, epidemiology, diagnosis, and management

Vulvar intraepithelial neoplasia (VIN) is classified into two entities: differentiated (dVIN) and vulvar high-grade squamous intraepithelial lesions (vH-SIL). dVIN is a premalignant lesion that develops on an existing vulvar lesion such as lichen sclerosus, while vH-SIL is associated with HPV infection. The two entities differ in terms of pathophysiology, background, prognosis, and management. The incidence of VIN in young women is rising and recurrence is common, even after radical surgery, which can cause significant disfigurement. Alternative strategies include topical treatments, ablation, and a watch-and-wait approach. There is currently no consensus on how these lesions should be managed. We review the literature in this field.