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

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.