Identification of high risk pathological node positive penile carcinoma: value of preoperative computerized tomography imaging.

PURPOSE: Patients with penile carcinoma, and 3 or more histopathologically proven unilateral metastatic inguinal nodes, and/or extranodal extension, and/or pelvic metastasis are considered a subgroup with prognostically unfavorable parameters for disease specific death and local recurrence after inguinal lymphadenectomy. We established radiographic criteria for the preoperative identification of such patients.

MATERIALS AND METHODS: Preoperative diagnostic computerized tomography studies of 30 patients with penile carcinoma with proven unilateral or bilateral lymph node metastasis were reviewed independently by 2 radiologists blinded for patient data. All computerized tomography images were analyzed per side (60). Several radiographic criteria were assessed for regional lymph nodes with short-axis diameter 8 mm or greater and/or central nodal necrosis. Sides were characterized as high risk if histopathology revealed 3 or more metastatic inguinal nodes and/or extranodal extension and/or pelvic nodal involvement.

RESULTS: Histopathological nodal involvement was found in 38 sides (63%) including 22 sides (37%) defined as high risk. The presence of central nodal necrosis and/or irregular nodal border of the regional lymph nodes on the preoperative computerized tomography identified the high risk subgroup with a sensitivity of 95% (21 of 22) and a specificity of 82% (31 of 38). All 7 sides falsely designated as high risk harbored inguinal metastases but they were classified as low risk. The interobserver agreement of each radiographic parameter was almost perfect.

CONCLUSIONS: The presence of central nodal necrosis and/or an irregular nodal border of the regional lymph nodes on preoperative computerized tomography images are accurate and reproducible criteria to identify high risk pathological node positive penile cancer. These criteria can be used for risk stratification and patient counseling.