Survival outcomes in early-stage cutaneous desmoplastic melanoma: A National Cancer Database analysis.

Abstract

e21577 Background: Desmoplastic melanoma (DM) is a rare subtype of melanoma characterized by spindle-shaped tumor cells within a fibrous stroma. Factors influencing survival in early-stage DM remain understudied in the US population. This study evaluates demographic, clinical, and treatment-related predictors of survival in early-stage DM to identify gaps in care and improve patient outcomes. Methods: Using the National Cancer Database (NCBD), we conducted a retrospective analysis of patients diagnosed with early-stage (AJCC stage I and II) cutaneous desmoplastic melanoma between 2010 and 2017. The primary cohort included patients who underwent surgery (S), or systemic therapy with surgery (ST+S). Kaplan-Meier survival analysis and accelerated failure time model (AFT) were used for survival analysis. First quartile survival time (Q1) was calculated given insufficient number of deaths to calculate median overall survival. STROBE guidelines were followed for reporting. Results: A total of 2,963 patients with desmoplastic melanoma were included. Of these, 2,051 (69.08%) were aged ≥65 years, 2,036 (68.58%) were male, 2,938 (98.96%) were White, 1,827 (61.54%) had Medicare insurance and 1,576 (53.08%) received care at Academic/Research Programs. 2897 (97.57%) underwent surgery (S), and 67 (2.25%) received systemic therapy in addition to surgery (ST+S). Q1 survival was 61.08 months for Surgery versus 100.17 months for combination ST+S group. However, after covariate adjustment, this survival benefit was found to be statistically insignificant (HR 0.62; p value 0.07). Female gender (HR 0.79, p = 0.003, CI 0.68–0.92) and private insurance were linked to better survival outcomes (HR 0.74, p = 0.008, CI 0.59–0.92). Race, treatment facility and other insurance types did not significantly predict mortality (p values > 0.05). Older age (>65) (HR 4.44, p < 0.001, CI 3.34–5.89), Charlson-Deyo Score (CDS) 1 (HR 1.24, p = 0.009, CI 1.05–1.47), CDS ≥3 (vs 0; HR 2.71, p < 0.001, CI 1.87–3.94), and TNM T4 were linked to worse outcomes (HR 1.43, p = 0.008). Additionally, treatment delay beyond 30 days of diagnosis (HR 1.30, p < 0.001) and receipt of care in the South-Atlantic (HR 1.48, p = 0.018), East North Central (HR 1.47, p = 0.031), East South Central (HR 1.92, p = 0.001), and West South-Central regions (HR 1.44, p = 0.048), compared to the Northeast, were also associated with worse survival outcomes. Conclusions: While combination of surgery and systemic therapy demonstrated higher Q1 survival, covariate-adjusted analysis found no statistically significant survival benefit over surgery alone. Older age, advanced TNM stage, and higher Charlson-Deyo Scores were linked to worse outcomes. Additionally, treatment delays and regional disparities further impacted survival, underscoring the need for timely and equitable treatment strategies.