Sentinel Lymph Node Dissection for Primary Cutaneous Melanoma: A Community Hospital's Initial Experience

Abstract

Management of the regional lymph nodes remains the most controversial aspect of treating patients with intermediate-thickness cutaneous melanoma. Prospective studies have failed to demonstrate a significant survival advantage for patients undergoing elective lymph node dissection. The sentinel lymph node dissection (SLND) technique has been proposed as a method of accurately identifying patients with occult metastases in whom a regional lymph node dissection would be indicated. The majority of studies evaluating this technique have come from academic centers, most with dedicated melanoma clinics. This report describes the initial experience with SLND at a community hospital. Fifteen patients with intermediate-thickness primary cutaneous melanoma underwent preoperative lymphoscintigraphy with 99Tc-sulfur colloid. In addition, intraoperative lymphatic mapping using intradermally injected isosulfan blue was performed. Dissection was guided by radioactivity levels (in counts per second) as measured by a hand-held gamma probe. The resected lymph node or nodes were evaluated for micrometastases using routine hematoxylin and eosin staining and immunohistochemistry with S-100 and HMB-45. All patients were followed clinically for any evidence of recurrence. A sentinel node(s) was identified on preoperative lymphoscintigraphy in all 15 patients (100%). A single sentinel node was identified in 11 of 15 (73%), two nodes in 3 (20%), and one node in 1 (6.7%). The hand-held gamma probe reading correlated well with the site marked the “hot spot” (600–15,320 cps for the hot spot versus 10–350 cps for background). The sentinel lymph node was successfully identified and resected in all 15 patients. Blue-stained lymphatics and/or lymph nodes were present in 8 of 15 (53%) cases. Histopathology was negative for evidence of occult micrometastases in all patients. At mean follow-up of 221 days, all 15 patients remain with no evidence of disease. The outcomes for mapping and harvesting the sentinel node at a community institution compare favorably with results at major academic institutions. SLND may therefore be offered to patients with intermediate-thickness cutaneous melanoma in the community hospital setting with regional lymph node dissection and adjuvant interferon α-2b as options for patients with nodal micrometastases.