Patterns of recurrence and survival in vulvar cancer: A nationwide population-based study.

ABSTRACT

OBJECTIVE: To examine the patterns of recurrence and how these patterns are associated with survival in vulvar squamous cell carcinoma. We also explored the survival impact of surgical groin staging (SGS). METHODS: Nationwide population-based study including women diagnosed with vulvar squamous cell carcinoma between 2012 and 2015 and registered in the Swedish Quality Registry for Gynecologic Cancer. Cumulative incidence rates (CIR), recurrence-free (RFS) and overall survival (OS) were calculated by Kaplan Meier estimates. The impact of SGS on RFS and OS was analyzed by proportional hazards models. RESULTS: 489 eligible women were included. Median follow-up time was 64 months. The overall recurrence rate was 22.3%. Site of recurrence local in 61.0%, groin in 30.0%, distant in 9.0%. The CIR for local recurrences increased with time (5.9% at 2-years, 14.7% at 5-years) while the rate of groin and distant recurrences was nearly steady (5.5% to 6.3% and 1.5% to 1.7%, respectively). Median 2-year and 4-year OS post-recurrence was 57.8% and 37.4% for local, 17.2%, 10.3% for groin and 0% for distant recurrences, respectively. SGS was omitted in 23.7% of surgically treated women with FIGO stages IB-II and significantly associated with worse RFS (Hazard ratio, HR, 1.9; 95%CI, 1.0-3.5; p = 0.04) and OS (HR 2.0; 95%CI, 1.1-3.8; p = 0.04) after adjustment for age, FIGO stage, tumor size, resection margins and performance status. CONCLUSION: The cumulative incidence of isolated vulvar recurrence was low but for those affected the prognosis was poor. Surgical groin staging is a crucial part of primary treatment and should not be omitted.