Establishing Criteria for Bilateral Pelvic Lymph Node Dissection in the Management of Penile Cancer: Lessons Learned from an International Multicenter Collaboration

Abstract

Penile carcinoma with bilateral pelvic lymph node metastasis is a relatively rare condition with poor outcomes. There are little data available on optimal strategies for staging and treating this group of patients. We assessed factors predicting bilateral pelvic lymph node metastasis in patients with penile cancer and confirmed inguinal lymph node metastasis. Multi-institutional data from a total of 4 centers in Europe, the People's Republic of China and the United States were retrospectively analyzed. Patients with penile carcinoma and inguinal lymph node metastasis who underwent bilateral pelvic lymphadenectomy were included in analysis. The Kaplan-Meier and log rank tests were used to express overall survival. Logistic regression was used for multivariate analysis of factors predicting bilateral pelvic lymph node metastasis. Cox regression was done in the multivariable analysis of overall survival. We identified 140 patients with penile carcinoma who had confirmed pelvic lymph node metastasis. Of the patients 83 had bilateral inguinal lymph node metastasis and 64 underwent bilateral pelvic lymphadenectomy. Bilateral pelvic lymph node metastasis was observed in 16 patients (25%). The ROC of the total number of inguinal lymph node metastases and the detection of bilateral pelvic lymph node metastasis had an AUC of 0.76 (p = 0.002) with 95% sensitivity for the cutoff point of 4 inguinal nodes. On logistic regression analysis the detection of 4 or more positive inguinal nodes was the only independent predictor of bilateral pelvic lymph node metastasis (OR 14.0, CI 1.71-115). On Cox regression analysis 4 or more inguinal lymph node metastases, adjuvant chemotherapy, inguinal extraprostatic extension and bilateral procedures were associated with overall survival. Patients with bilateral inguinal lymph node metastasis who are treated with unilateral pelvic lymphadenectomy should be considered for bilateral pelvic lymphadenectomy in the presence of 4 or more metastatic inguinal nodes.