Lymphatic mapping and sentinel node biopsy for melanoma.

Worldwide experience has now confirmed that the histological status of sentinel nodes (SNs) accurately reflects the status of regional lymph nodes in patients with melanoma. Preoperative lymphoscintigraphy has proved to be invaluable in identifying SNs and in demonstrating unusual lymphatic drainage pathways. Greatest accuracy at the time of surgery is achieved using both blue dye injection and a gamma-probe. Close cooperation between surgeons, nuclear medicine physicians and pathologists is required if the SN biopsy technique is to be reliable. The results of clinical trials will demonstrate whether SN biopsy has any therapeutic value. It is already clear, however, that SN examination provides very accurate staging, and SN biopsy is therefore essential for all melanoma patients entering adjuvant therapy trials.