PREDICTION OF POTENTIAL METASTATIC SITES IN CUTANEOUS HEAD AND NECK MELANOMA USING LYMPHOSCINTIGRAPHY

BACKGROUND: The technique of lymphoscintigraphy may allow a more selec tive approach to the management of clinically negative neck nodes amon g patients with cutaneous head and neck melanoma. PATIENTS AND METHODS : A group of 97 patients with cutaneous head and neck melanoma had pre operative lymphoscintigraphy using intradermal injections of technetiu m 99m antimony trisulfide colloid to identify sentinel nodes. Fifty-on e patients were eligible for clinical analysis after initial definitiv e treatment by wide excision only (n = 11), wide excision and elective dissection of the neck (n = 19) or axilla (n = 1), or wide excision a nd a sentinel node biopsy procedure (n = 20). RESULTS: Sentinel nodes were identified in 95 of 97 lymphoscintigrams, and 85% of patients had multiple sentinel nodes. In 21 patients (22%), sentinel nodes were id entified outside the parotid region and the 5 main neck levels, mostly in postauricular nodes (n = 13), Lymphoscintigrams were discordant wi th clinical predictions in 33 patients (34%), Lymph nodes were positiv e in 4 elective dissections and 4 sentinel node biopsies. Among 16 pat ients evaluable after wide excision and a negative sentinel node biops y, 4 patients subsequently developed metastatic nodes; however, confid ent identification of all nodes marked as sentinel nodes on lymphoscin tigraphy was not achieved at the original biopsy procedure in 3 of the se patients. CONCLUSIONS: Lymphoscintigraphy and sentinel node biopsy are more difficult to perform in the head and neck than in other parts of the body. The reliability of sentinel node biopsy based on lymphos cintigraphy may be improved by identifying and marking all nodes that are considered to receive direct lymphatic drainage from the primary m elanoma, and by use of a gamma probe intraoperatively.