Radio-guided lymph node surgery in urethral and penile cancer

Purpose: At the end of the 1970s, Cabanas postulated the existence of reproducible sentinel lymph nodes (SLN) located medial to the saphenofemoral junction by means of lymphangiography. The lack of reproducibility of SLN in penile carcinoma as to its defined localization was later emphasized by numerous investigations in which patients with gross lymphatic metastases could be monitored despite negative biopsies of the "Cabanas lymph node". The high morbidity of inguinal lymphadenectomy and the individual variability regarding the location of SLN justified the necessity for a technique which enables identification of these nodes. It was the aim of this study to determine whether preoperative lymphoscintigraphy and intraoperative gamma probe-guided lymph node detection was able to identify the SLN. Material and methods: Since 1998, SLN were identified intraoperatively and selectively dissected in 6 patients with penile or urethral cancer after peritumoral injection of technetium-99m nanocolloid and performance of lymphoscintigraphy. Results: At least one SLN could be detected in each patient. The maximum surgical time for sentinel lymphadenectomy was 30 minutes. There were no severe complications. Lymph node metastases were found in one patient in one sentinel lymph node. After a mean follow-up of 16 months, all patients are currently tumor-free. Conclusions: Due to the long-term results of sentinel lymphadenectomy in malignant melanoma of other locations and our preliminary results in urethral and penile cancer, we consider this method to be appropriate as the only primary operation for lymph node staging in early stages and, in combination with modified inguinal lymphadenectomy, in locally advanced stages.