2733 - Management of Recurrent Vulvar Squamous Carcinoma: Patterns of Disease Control and Survival Post-Radiation

10:45am - 12:00pm PT

Hall F

Screen: 13

POSTER

Presenter(s)

Cecilia de Sousa, MD, MPH - Johns Hopkins Medicine, Baltimore, MD

C. F. P. M. de Sousa¹, R. L. Stone², and A. N. Viswanathan¹; ¹Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, ²Johns Hopkins Hospital, Department of Gynecology and Obstetrics-Gynecologic Oncology, Baltimore, MD

Purpose/Objective(s): Recurrent vulvar cancer presents unique challenges due to the complexities of previous treatments and individual clinical presentations. Given the limited data guiding treatment decisions, this study aims to describe the patterns of disease control and survival following radiation therapy (RT) for recurrent vulvar cancer, underlining the importance of multidisciplinary approaches.

Materials/Methods: We reviewed vulvar cancer cases treated with RT (2016 – 2024) at our institution. Locoregional failure (LRF) was estimated using the Aalen-Johansen Fitter. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method and compared with the log-rank test. Doses are reported in EQD2 (a/ß=10), with significance set at p < 0.05.

Results: Of 55 vulvar cancer cases reviewed, 13 (23.6%) were loco-regional recurrent squamous carcinoma. The median age at recurrence was 71.3 years (IQR 51.3-80.5). The median time from the initial diagnosis to recurrence was 32 months (IQR 4-171), with a median follow-up (FU) post-recurrence of 28.7 months (IQR 11.4-44.9). Of the 13 recurrences, 8 (62%) were vulvar (1 with adjacent organ invasion); 4 (31) vulvar and nodal (2 inguinal, and 2 inguinal and pelvic); and 1 (8%) inguinal-only. Treatments before recurrence included surgery alone (70%) and surgery plus adjuvant RT (30%).

Most patients (62%, 8/13) underwent surgery to resect local recurrence before RT, 5 (40%) received concurrent chemotherapy, and 4 (31%) were re-irradiated (re-RT). For RT, 7 (54%) had external beam (EB) alone, 5 (38%) had EB + brachytherapy (BT), and 1 (8%) had BT alone. Re-RT cases received a median of 42.9 Gy (range 15.8 – 62.6), whereas those receiving adjuvant treatment 58.4 Gy (49.7 – 68.2), and RT only (EB and BT) 77.4 Gy (70.1 – 84.6).

The cumulative incidence of LRF at 24 and 60 months was 16.7% and 31.3%, and the median was not reached. Median PFS was 52 months for patients with vulvar-only recurrence and 33 months for patients with node-positive or adjacent organ invasion (p = 0.2). Median OS was 52 months, and 2 and 5-year OS was 81.5% and 36.2%.

At last FU, 46% (6/13) of patients were alive without disease, including 2 who received re-RT and 1 who had a local and inguinal recurrence (26 months FU). Additionally, 15% (2/13) were alive with disease, 23% (3/13) died with disease (2 nodal recurrences), and 15% (2/13) died without disease.

Adverse effects included a urethrovaginal fistula (84.6 Gy EBRT/interstitial BT for urethral recurrence) and vaginal necrosis (41.9Gy interstitial BT re-RT for vaginal recurrence); neither experienced relapse.

Conclusion: RT is an important component of vulvar cancer management that can lead to durable control even in the recurrent scenario. These findings underscore the importance of a multidisciplinary, individualized treatment approach and support further research into personalized treatment protocols that tailor the integration of therapies based on patient-specific factors in order to optimize outcomes.