Health care system and socioeconomic factors associated with variance in use of sentinel lymph node biopsy for melanoma in the United States.

PURPOSE: Guidelines recommend sentinel lymph node biopsy (SLNB) for patients with clinical stage IB/II melanomas, but not clinical stage IA melanoma. This study examines factors associated with SLNB use for clinically node-negative melanoma.
METHODS: Patients diagnosed with clinically node-negative invasive melanoma in 2004 and 2005 were identified from the National Cancer Data Base. Regression models were developed to assess the association of clinicopathologic (sex, age, race/ethnicity, comorbidities, T stage), socioeconomic (insurance status, educational level, income), and hospital (hospital type, geographic area) factors with SLNB use.
RESULTS: A total of 16,598 patients were identified: 8,073 patients with clinical stage IA and 8,525 patients with clinical stage IB/II melanoma. For clinical stage IB/II melanoma, SLNB use was reported in 48.7% of patients. Patients with clinical stage IB/II melanoma were less likely to undergo SLNB if they were older than 75 years; had T1b tumors, no tumor ulceration, or head/neck or truncal lesions; were covered by Medicaid or Medicare; or lived in the Northeast, South, or West census regions. SLNB use was reported in 13.3% of patients with clinical stage IA melanoma and was more likely in patients who were younger than 56 years or lived in the Mountain or Pacific census regions. Patients treated at National Comprehensive Cancer Network-or National Cancer Institute-designated hospitals were most likely to undergo SLNB in adherence with national consensus guidelines.
CONCLUSION: SLNB use was associated with clinicopathologic factors but also with health system factors, including type of insurance, geographic area, and hospital type. These findings have implications for provider education and health policy.