Survival outcomes for patients with stage IVB vulvar cancer with grossly positive pelvic lymph nodes: time to reconsider the FIGO staging system?

Objective: To evaluate treatment outcomes for patients with vulvar cancer with grossly positive pelvic lymph nodes (PLNs).

Methods: From a database of 516 patients with vulvar cancer, we identified patients with grossly positive PLNs without distant metastasis at initial diagnosis. We identified 20 patients with grossly positive PLNs; inclusion criteria included PLN 1.5cm or larger in short axis dimension on CT/MRI (n=11), FDG-avid PLN on PET/CT (n=3), or biopsy-proven PLN disease (n=6). Ten patients were treated with chemoradiation therapy (CRT), 4 with RT alone, and 6 with various combinations of surgery, RT or CRT. Median follow-up time for patients who had not died of cancer was 47months (range, 4-228months).

Results: Mean primary vulvar tumor size was 6.4cm; 12 patients presented with 2009 AJCC T2 and 8 with T3 disease. All patients had grossly positive inguinal nodes, and the mean inguinal nodal diameter was 2.8cm. The 5-year overall survival and disease specific survival rates were 43% and 48%, respectively. Eleven patients had recurrences, some at multiple sites. There were 9 recurrences in the vulva, but no isolated nodal recurrences. Four patients developed distant metastasis within 6months of starting radiation therapy.

Conclusions: Aggressive locoregional treatment can lead to favorable outcomes for many patients with grossly involved PLNs that is comparable to that of grossly involved inguinal nodes only. We recommend modification of the FIGO stage IVB classification to more accurately reflect the relatively favorable prognosis of patients with PLN involvement.