Objectives: The aim of the current study was, first, to determine whether laterality of lymph node metastases has prognostic significance, independent of the number of lymph node metastases. Second was to determine the prognostic significance of extracapsular spread irrespective of the number of lymph node metastases.

Methods: Data on 134 patients with stage III/IVA vulva cancer from 1982 till 2004 and treated with curative intent in either the Academic Medical Centre in Amsterdam or the Mercy Hospital for Women in Melbourne were reviewed. The impact of the number of lymph node metastases, extracapsular spread, and bilateral existence of lymph node metastases on survival was determined.

Results: The bilateral presence of lymph node metastases is not a significant predictor for survival if a correction is made for the number of lymph node metastases (hazards ratio, 1.31; 95% confidence interval, 0.68-2.51; P = 0.420). If extracapsular spread is put into the model as well, this is the only parameter of prognostic significance in multivariate analysis (hazards ratio, 5.27; 95% confidence interval, 2.60-10.67; P < 0.001). The five-year survival of patients with extracapsular spread is only 31%, which is considerably lower than the 80% survival of patients with only intracapsular metastases.

Conclusions: In conclusion, there is growing evidence that bilateral existence of lymph node metastases is not a sufficient variable to qualify stage. Extracapsular spread, however, seems to be the most valuable lymph node-associated prognostic factor for survival.