Population-based analysis of lymphatic mapping and sentinel lymphadenectomy utilization for intermediate thickness melanoma

BACKGROUND AND OBJECTIVES: Lymphatic mapping and sentinel lymphadenectomy (LM/SL) is the nodal staging procedure of choice for patients with intermediate thickness melanoma. We hypothesize that a significant portion of these patients are not undergoing LM/SL. We explore factors that influence use of LM/SL. METHODS: Analysis was performed of all incident cases of invasive cutaneous melanoma in North Carolina between January 1, 1999 and December 31, 2001. RESULTS: Three thousand four hundred and thirty-six cases of melanoma were reported for 1999-2001. Two hundred and seventy-three cases (8%) were excluded due to metastases. Nine hundred and sixteen cases (29%) were excluded because the T classification was not reported. Of the remaining cases, 1,242 (55%) were intermediate thickness (T2-3); 48% (596/1,242) underwent LM/SL. Subjects >or=60 years old were less likely to receive LM/SL than subjects <60 years (39% vs. 55.4%, P < 0.001). Subjects with head/neck primary tumors were less likely to receive LM/SL than other subjects (33% vs. 51%, P < 0.001). Subjects with T3 tumors were more likely to receive LM/SL than those with T2 tumors (54% vs. 42%, P < 0.001). CONCLUSIONS: Half of all patients with intermediate thickness melanoma in North Carolina do not receive LM/SL. Use of LM/SL varies by patient age and primary tumor site. Further investigation is warranted to explore these differences.