Diagnosis and Staging in Penile Cancer

Abstract

Penile cancer is usually an obvious visual diagnosis but may be hidden under a phimosis and always requires histological confirmation. Superficial forms may appear as innocuous changes in color and texture of the glandular skin. A high degree of diagnostic suspicion and early biopsy are required in such cases. Palpation of the primary tumor will give relevant information on the local extent, and additional penile imaging is usually not needed. Since metastatic lymphatic spread occurs early in penile cancer and can quickly lead to disseminated disease, examination of the regional inguinal lymph nodes is essential. Groin palpation remains the most useful examination to detect suspicious lymph nodes. Imaging can confirm palpably enlarged lymph nodes and may only be additionally useful in obese patients or for pelvic node staging. But no imaging modality can reliably exclude micrometastatic disease in clinically normal inguinal lymph nodes which occurs in up to 25% of cases. This can only reliably be done by invasive lymph node staging of inguinal nodes removed by sentinel lymph node biopsy or limited modified lymphadenectomy. In case of enlarged and suspicious inguinal lymph nodes, imaging to detect pelvic nodes and distant metastasis by CT, MRI, or PET/CT scanning can be required in addition to pathological staging by radical inguinal lymphadenectomy followed by ipsilateral pelvic lymphadenectomy if more than one inguinal node is affected. Thus, diagnosis and staging in penile cancer remains mostly clinical and surgical.