Treatment patterns and outcomes in perineal primary vulvar cancer-a population-based Swedish cohort study

The choice of treatment for vulvar squamous cell carcinoma involving the perineum is challenging because of its anatomical proximity to the anus. The study aim was to describe treatment patterns, complications, and survival of women with perineal vulvar squamous cell carcinoma.

A population-based study at two tertiary referral hospitals during 2012-2020. Demographic and clinical data were retrieved from medical records. Survival and complications were analyzed according to treatment modality. Relative and progression-free survival were calculated by Kaplan-Meier estimates.

The cohort comprised 571 women with primary vulvar squamous cell carcinoma, of which 147 (26%) were located at the perineum. Seventy-eight women (78/147; 53%) underwent surgery only with a median resection margin of 5 mm. In 34/147 women (23%), surgery was followed by adjuvant radiotherapy because of lymph node metastasis (74%) and/or insufficient margins (median resection margin 1.6 mm). Primary radiotherapy was delivered to 35/147 women (24%). Treatment-related complications during the first year were recorded in 47% after surgery only, in 79% after adjuvant radiotherapy and in 71% after primary radiotherapy. After a median follow-up of 41 months, disease progression occurred in 3% of women treated with surgery only, in 18% after adjuvant radiotherapy and in 33% after primary radiotherapy. The 2-year progression-free survival was 82% (95% CI, 74-91) after surgery only, 53% (95% CI, 38-73) after adjuvant radiotherapy, and 31% (95% CI, 19-51) after primary radiotherapy.

When diagnosed at an early-stage, perineal vulvar squamous cell carcinoma can successfully be treated by primary surgery. The optimal treatment strategy for advanced disease remains uncertain and requires further investigation.