Sentinel node biopsy for malignant melanoma: a staging procedure only?

Sentinel node biopsy (SNB) is an established staging tool for malignant melanoma. It allows identification of patients with metastatic disease at a very early stage and to collect accurate and complete prognostic information for these patients. Having noted that in a relevant percentage of patients the sentinel node is the only site of metastases, some authors have postulated a therapeutic role for SNB. In this paper, the possibility of a therapeutic role of SNB is evaluated. Relevant literature on the topic has been analyzed. Several findings suggest that not all patients with a positive SNB have further lymph node involvement. The prognostic indicators currently available do not significantly correlate with non-sentinel node (NSN) involvement. It seems that more than morphological data of the tumor and of the lymph node metastasis, biologic markers may be investigated to understand tumor behavior and predict NSN involvement. At present, SNB must still be considered a staging procedure only and an appealing field of research to understand the behavior of melanoma. Better understanding of the biology of melanoma and of the host’s immune response towards it may lead to identification of those patients with the sentinel node as the only site of metastases.