Abstract
Some patients presenting with cutaneous malignant melanoma without palpable adenopathy have regional metastatic disease. We have applied the technique of gamma probe-directed selective lymph node biopsy and used the results to direct further therapy. The results of a prospective nonrandomized clinical study are presented. Between November 1993 and December 1996, 63 patients with a diagnosis of primary cutaneous malignant melanoma underwent lymphoscintigraphy with technetium sulfur colloid followed by gamma probe- guided lymph node biopsy. There were 32 (51%) women and 31 (49%) men with a mean age of 51.1 years (median, 50; range, 13-87). Mean Breslow thickness was 2.13 mm (range, 0.5-15.0 mm; median, 1.56 mm). Primary locations were head and neck in 8 (13%), trunk in 24 (38%), upper extremity in 13 (21%), and lower extremity in 18 (29%). Selective lymph node biopsy was done on an outpatient basis with local anesthesia in 49 cases (78%) and in the operating room with general anesthetic in 14 patients (22%). One lymph node site was biopsied in 46 patients (73%), two sites in 16 (25%), and three in 1 (2%), for a total of 81 selective lymph node biopsy sites, mean 1.29 per patient. The mean number of labeled lymph nodes removed per site per patient was 1.64 (range, 1-5). Seroma or infection occurred in 6 patients (10%). Micrometastatic disease was identified in nine selective lymph node biopsy sites in eight patients. Of eight patients undergoing lymph node dissection, 5 (63%) had no additional pathological lymph node involvement. With a mean follow-up of 579 days from selective lymph node biopsy (median, 594; range, 36-1157), 59 (94%) have no evidence of disease. Three patients have died, 2 with systemic disease (475 and 1149 days) and 1 from a myocardial infarction (380 days). No patient has failed with regional-only recurrence. Gamma probe- directed selective lymph node biopsy is a straightforward procedure that can be done in the outpatient setting and facilitates management of patients with cutaneous malignant melanoma.