Prediction of potential metastatic sites in cutaneous head and neck melanoma using lymphoscintigraphy.

BACKGROUND: The technique of lymphoscintigraphy may allow a more selective approach to the management of clinically negative neck nodes among patients with cutaneous head and neck melanoma.

PATIENTS AND METHODS: A group of 97 patients with cutaneous head and neck melanoma had preoperative lymphoscintigraphy using intradermal injections of technetium 99m antimony trisulfide colloid to identify sentinel nodes. Fifty-one patients were eligible for clinical analysis after initial definitive treatment by wide excision only (n = 11), wide excision and elective dissection of the neck (n = 19) or axilla (n = 1), or wide excision and 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 identified outside the parotid region and the 5 main neck levels, mostly in postauricular nodes (n = 13). Lymphoscintigrams were discordant with clinical predictions in 33 patients (34%). Lymph nodes were positive in 4 elective dissections and 4 sentinel node biopsies. Among 16 patients evaluable after wide excision and a negative sentinel node biopsy, 4 patients subsequently developed metastatic nodes; however, confident identification of all nodes marked as sentinel nodes on lymphoscintigraphy was not achieved at the original biopsy procedure in 3 of these 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 lymphoscintigraphy may be improved by identifying and marking all nodes that are considered to receive direct lymphatic drainage from the primary melanoma, and by use of a gamma probe intraoperatively.