The objective of the current study was to identify independent clinical and pathologic variables that were predictive of lymph node involvement in patients with squamous cell carcinoma of the penis in a multicenter series with the intent to select patients who were suitable to undergo immediate inguinal lymphadenectomy.

Data were analyzed from 175 patients who underwent surgery for penile carcinoma in 11 urologic centers participating in the Gruppo Uro-Oncologico del Nord-Est (Northeast Uro-Oncological Group) Penile Cancer Data Base. Pathologically positive lymph nodes were defined as the presence of histologically confirmed lymph node metastasis in patients who underwent either immediate or delayed inguinal and/or pelvic lymphadenectomy. Patients who had clinically positive lymph nodes with cytologically positive fine-needle aspiration results and who had not undergone lymphadenectomy were censored.

Overall, lymph-node involvement was observed in 71 of 175 patients (40.6%) included in the analyses. After analyzing the whole group of patients, the following variables were identified as independent predictors of pathologic lymph node metastasis: clinical lymph node status, pathologic stage of the primary tumor, venous and lymphatic embolizations, and histologic grade. In the subgroup of patients with clinically negative lymph nodes, tumor thickness, histologic grade, lymphatic and venous embolizations, infiltration of both corpus spongiosum and urethra, and pathologic stage of the primary tumor (according to the 1997 TNM classification system) were predictive of lymph node involvement on univariate analysis. The generated logistic regression model showed that venous and/or lymphatic embolizations and infiltration of the corpus spongiosum and/or urethra were independent predictors of pathologic lymph node metastasis in patients with clinically negative lymph nodes.

Venous and/or lymphatic embolizations played relevant roles as predictors of pathologic lymph node involvement in patients with penile neoplasia and should be considered important parameters in determining which patients with clinically negative lymph nodes should undergo immediate lymphadenectomy.