Sentinel node biopsy in melanoma.

There has, for a long time, been an ongoing discussion on whether the prophylactic removal of lymph nodes ("elective lymph node dissection") is of benefit for melanoma patients. More recently, "selective" lymphadenectomy ("sentinel node biopsy", SNB) has been proposed to evaluate the status of the first draining lymph node ("sentinel node") of the regional basin. Several studies now demonstrate that the sentinel node evaluation for underlying metastatic disease reflects the status of the entire lymph node region and is therefore a useful prognostic factor. A multi-institutional study highlighted SNB status as the most significant prognostic factor, superior to measurement of tumor thickness in primary melanoma. Different techniques to detect micrometastasis within the lymph node are under current evaluation. Histology and immunohistology using antibodies against melanoma-associated antigens are routinely performed in SNs. The clinical value of reverse-transcriptase polymerase chain reaction (RT-PCR)based search for minimal melanoma disease in lymph nodes remains unclear.