Klapdor R, et al. - Given the significance of lymph node (LN) metastasis as a prognostic factor in primary vulvar cancer, researchers sought for risk factors for the incidence and extent of LN metastases that may assist selecting the optimal treatment strategy for each individual patient. All patients (n=1162) treated with radical groin dissection from the large multicenter AGO-CaRE-1 study were included in this subgroup analysis. Outcomes revealed that LN metastasis prevalence had the strongest correlation to lymphvascular space invasion, tumor stage, and depth of infiltration. Tumor stage or tumor diameter are noted to be correlated with the number of LN metastases.