34151 Association of type II diabetes mellitus with characteristics and outcomes for patients undergoing sentinel lymph node biopsy for cutaneous melanoma

Background: Limited data exist describing patients with type II diabetes mellitus (T2DM) who are diagnosed with clinically localized primary cutaneous melanoma and require sentinel lymph node (SLN) biopsy. Methods: Consecutive patients diagnosed with AJCC clinical Stage I-II melanoma who underwent wide excision and SLN biopsy at a single institution (2007-2016) were identified, and patients with and without T2DM at the time of melanoma diagnosis were compared using logistic regression analysis. Patients were further stratified by whether their T2DM was non-insulin dependent (NID-T2DM) or insulin dependent (ID-T2DM). Associations between factors and outcomes were analyzed using Cox proportional hazards regression analysis. Results: Of the 1128 patients evaluated, 111 (9.8%) had T2DM (n = 94 [84.7%] NID-T2DM; n = 17 [15.3%] ID-T2DM). On multivariable analysis controlling for patient and tumor factors, T2DM patients were more likely to be older (odds ratio [OR] 1.04, p 1.0 mm thick (OR 1.91, P = .019), and have microsatellitosis (OR 2.27, P = .029). Ten-year cumulative incidence of melanoma recurrence was significantly greater for those with ID-T2DM (64.4% ID-T2DM vs. 34.4% NID-T2DM vs. 21.8% no T2DM, P < .001). On multivariable analysis, ID-T2DM was independently associated with melanoma recurrence (hazard ratio [HR] 2.58, P = .015); this association was not seen with NID-T2DM (HR 0.82, P = .421). Conclusion: Patients with insulin-dependent type II diabetes mellitus appear to present with more advanced melanoma and are at increased risk for melanoma recurrence. Further study as to whether this reflects differences in tumor biology or host differences in immune response is warranted.