Radiation therapy compared with pelvic node resection for node-positive vulvar cancer: a randomized controlled trial.

OBJECTIVES: To report long-term survival and toxicity of radiation compared with pelvic node resection for patients with groin node-positive vulvar cancer.

METHODS: A Gynecologic Oncology Group protocol enrolled 114 patients randomly allocated to postoperative pelvic and groin radiation (45-50 Gy, n=59) or to ipsilateral pelvic node resection (n=55) after radical vulvectomy and inguinal lymphadenectomy. Retrospective analyses for 114 enrolled patients included both risk of progression and death after treatment and assessment of toxicity.

RESULTS: Median age was 70 years. Median survivor follow-up was 74 months. The relative risk of progression was 39% in radiation patients (95% confidence interval [CI] 0.17-0.88, P=.02). Fourteen intercurrent deaths occurred after radiation as compared with only two after pelvic node resection, narrowing 6-year overall survival (51% compared with 41%, hazard ratio 0.61 [95% CI 0.30-1.3], P=.18). However, the cancer-related death rate was significantly higher for pelvic node resection compared with radiation (51% compared with 29% at 6 years, hazard ratio 0.49 [95% CI 0.28-0.87], P=.015). Six-year overall survival benefit for radiation in patients with clinically suspected or fixed ulcerated groin nodes (P=.004) and two or more positive groin nodes (P<.001) persisted. A ratio of more than 20% positive ipsilateral groin nodes (number positive/number resected) was significantly associated with contralateral lymph node metastasis, relapse, and cancer-related death. Late chronic lymphedema (16% compared with 22%) and cutaneous desquamation (19% compared with 15%) were balanced after radiation and pelvic node resection.

CONCLUSION: Radiation after radical vulvectomy and inguinal lymphadenectomy significantly reduces local relapses and decreases cancer-related deaths. Late toxicities remained similar after radiation or pelvic node resection.

LEVEL OF EVIDENCE: I.