Prospectively Packaged Ilioinguinal Lymphadenectomy for Penile Cancer: The Disseminative Pattern of Lymph Node Metastasis

Purpose: We prospectively evaluated the disseminative pattern of lymph node metastasis in penile cancer cases using packaged lymphadenectomy. In addition, we analyzed prognostic factors of the extent of lymph node metastasis. Materials and Methods: Packaged inguinal lymphadenectomy was performed in 46 patients. A total of 24 patients with 1 or more positive inguinal lymph nodes underwent packaged iliac lymphadenectomy. Inguinal lymphadenectomy was divided into 3 packages, including medial inguinal, lateral inguinal and Cloquet's node packages. Medial and lateral inguinal packages were separated by the lateral surface of the femoral artery and the saphenous vein. Iliac lymphadenectomy was divided into 3 packages, including external iliac, obturator and common iliac packages. Clinicopathological features of the primary tumor and lymph nodes were correlated with the extent of lymph node metastasis. Results: Of 92 groin basins 27 cases of inguinal. lymphadenectomy and 7 of iliac lymphadenectomy had lymph node metastasis. Medial inguinal and external iliac packages were the most common involved regions in inguinal. and iliac lymphadenectomy cases, respectively. No extended lymph node metastasis was observed in the absence of positive lymph nodes in the medial inguinal package. In groin basins with lymph node metastasis in the medial inguinal package extra-nodal extension was a significant predictor of extended lymph node metastasis. Cloquet's node was associated with iliac lymph node metastasis on univariate analysis. However, it was of limited predictive value in patients with 1 or 2 positive inguinal lymph nodes. Conclusions: The medial inguinal package defined in our study was the first involved lymph node region in penile cancer cases. Extranodal extension was an important predictor of extended lymph node metastasis beyond the medial inguinal package.