Pelvic lymphadenectomy in vulvar cancer and its impact on prognosis and outcome.

BACKGROUND: The value of pelvic lymphadenectomy (LAE) has been subject of discussions since the 1980s. This is mainly due to the fact that the relation between lymph node involvement of the groin and pelvis is poorly understood and therewith the need for pelvic treatment in general. PATIENTS AND METHODS: N = 514 patients with primary vulvar squamous cell cancer (VSCC) FIGO stage ≥ IB were treated at the University Medical Center Hamburg-Eppendorf between 1996 and 2018. In this analysis, patients with pelvic LAE (n = 21) were analyzed with regard to prognosis and the relation of groin and pelvic lymph node involvement. RESULTS: The majority had T1b/T2 tumors (n = 15, 78.9%) with a median diameter of 40 mm (11-110 mm). 17/21 patients showed positive inguinal nodes. Pelvic nodal involvement without groin metastases was not observed. 6/17 node-positive patients with positive groin nodes also had pelvic nodal metastases (35.3%; median number of affected pelvic nodes 2.5 (1-8)). These 6 patients were highly node positive with median 4.5 (2-9) affected groin nodes. With regard to the metastatic spread between groins and pelvis, no contralateral spread was observed. Five recurrences were observed after a median follow-up of 33.5 months. No pelvic recurrences were observed in the pelvic nodal positive group. Patients with pelvic metastasis at first diagnosis had a median progression-free survival of only 9.9 months and overall-survival of 31.1 months. CONCLUSION: A relevant risk for pelvic nodal involvement only seems to be present in highly node-positive disease, therefore pelvic staging (and radiotherapy) is probably unnecessary in the majority of patients with node-positive VSCC.