N. Shafique1, K. Rabidou2, M.S. Farooq1, G.M. Vargas1, T.C. Mitchell2, J.T. Miura1, G. Karakousis1 1Hospital of University of Pennsylvania, Endocrine And Oncologic Surgery, Philadelphia, PA, USA 2Hospital of University of Pennsylvania, Hematology/Oncology, Philadelphia, PA, USA
Introduction: With the advent of targeted therapies and immune checkpoint blockade, there are now effective therapies approved for patients with high risk stage III melanoma after surgical resection. We hypothesized that these therapies may be non-uniformly utilized across patient populations and health system types.
Methods: The National Cancer Database was queried to identify patients who were diagnosed with Stage III melanoma and underwent surgical resection between 2018 and 2021. The primary outcome of interest was treatment with adjuvant systemic therapy (AT). Patient demographic, tumor, and treatment facility factors were included. We used univariate and multivariable logistic regression to assess likelihood of receiving AT.
Results: The cohort was comprised of 18,533 patients with a median age of 64 years. The patients were predominately White (94%) and male (60.7% ). 23.4% patients had stage IIIA disease, 23.5% had stage IIIB, and the remaining had stage IIIC disease. Adjuvant therapy was used more frequently over time, with 68.1% of eligible patients receiving adjuvant therapy in 2021 compared to 63.5% in 2018 (p<0.001). There were several significant differences in patient, tumor, and treatment characteristics between patients who only underwent resection and those who received AT (Table 1). On multivariable analysis adjusting for patient demographic, tumor, and facility factors, AT patients were more likely to be younger (≥ 65 years of age odds ratio [OR]: 0.61, 95% confidence interval [95% CI] 0.55-0.67) and privately insured (government insurance [Medicare/Medicaid] OR: 0.83, 95% CI 0.76-0.91 and uninsured OR 0.58, 95% CI 0.47-0.71). Those with stage IIIB or IIIC melanoma (IIIB vs IIIA OR: 2.03, 1.85-2.22; IIIC vs IIIA OR: 2.43, 95% CI 2.25-2.63) and truncal tumors (OR vs extremity: 1.12, 95% CI: 1.04-1.17) were also more likely to recieve AT. Treatment at a community facility (OR vs academic 1.29; 95% CI 1.18-1.39) and at a facility ≤50 miles from the patients home (OR 1.29; 95% CI 1.17-1.42) was also associated with receipt of AT.
Conclusion: Adjuvant therapy has become increasingly more common with approval of effective therapies. However, a sizable number of eligible patients continue to be treated with surgical resection alone. Patients who are older, uninsured or with government insurance, and treated at academic facilities are less likely to receive adjuvant therapy. Efforts are needed to further identify disparities and standardize melanoma care in the United States, and oncologic surgeons should ensure appropriate discussion and referral for consideration of adjuvant therapy when indicated.