Carcinoma of the penis--appraisal of a modified tumour-staging system

To evaluate variables for the prediction of lymph node metastases in carcinoma of the penis, using a recently proposed modified tumour-staging system that combines the histological degree of differentiation and extent of local invasion of the primary tumour.

Thirty-five patients with squamous carcinoma of the penis and histo- or cytological staging of the inguinal lymph nodes were reviewed. A clinical TNM staging system was used in which the size (diameter) of the primary tumour and the clinical extent of invasion were considered. Subsequently, the tumours were also staged according to a modified T-system in which the histological degree of differentiation and pathological extent of tumour invasion were combined.

Penectomy was performed in 34 patients (partial amputation in 20 and radical penectomy in 17). Inguinal lymphadenectomy was performed in 31 patients and in four the presence of lymph node metastases was confirmed by aspiration cytology. Using the clinical TNM staging system, lymph node metastases were histo- or cytologically present in no patients with T1, in five of 19 with T2, in 10 of 13 with T3 and in both patients with T4 tumours. Lymph node metastases were present in two of eight patients without clinically palpable inguinal nodes, in three of 14 with nodes clinically thought to be infective and in 11 of 12 nodes clinically considered to be malignant. Lymph node metastases were present in five of 17 patients with grade 1, in nine of 13 with grade 2 and in three of five with grade 3 tumours. Using the modified histological T-staging system (T1 = grade 1-2, invasive through dermis; T2 = any grade, invasion of corpus spongiosum or cavernosum; T3 = any grade, invasion of urethra; T4 = grade 3, regardless of invasion) lymph node metastases were present in one of nine patients with T1, in eight of 16 with T2, in all five with T3 and in three of five with T4 tumours.

The modified T-staging system, which combines histological differentiation with pathological extent of invasion, provided the best predictive distinction between T1 and T2-4 tumours, indicating that lymphadenectomy can be avoided in T1 tumours, but should be performed in all patients with T2-4 tumours. We recommend bilateral inguinal lymphadenectomy 6-8 weeks after penectomy in such patients.