The impact of prevalent primary cancers in melanoma patients on survival

Abstract

Background The presence of prior malignancies at the time of cutaneous malignant melanoma diagnosis may be a critical determinant of patient survival. The present study evaluated the clinical and economic impact of prevalent cancers at the time of cutaneous melanoma diagnosis. Methods This population-based retrospective cohort study included melanoma cases identified in the Italian Veneto Region Cancer Registry (RTV) in 2019 and 2021. Prevalent primary cancers that occurred within a five-year interval prior to melanoma diagnosis were identified from the RTV’s multiple tumors dataset. Kaplan–Meier and Cox proportional hazards models were used to test the association between prevalent primary cancers and overall and melanoma-specific survival. Over three years, healthcare costs were analyzed from a health system perspective using administrative data. Results Out of 2,978 melanoma patients, 134 (4.5%) had prevalent tumors. The most frequent additional cancer sites were prostate (30.2%), breast (10.8%), colon (7.9%), and kidney (7.2%). Prevalent malignancies were associated with older age, male sex, and greater comorbidity burden in melanoma patients. In univariate Cox regression analysis, prevalent tumors were associated with an increased risk of all-cause mortality (HR 2.23, 95% CI 1.59–3.15; p<0.001), whereas no significant association was observed with CM-specific mortality. After adjustment for prognostic factors, prevalent tumors remained independently associated with an increased risk of all-cause mortality (aHR 1.72, 95% CI 1.19–2.47; p=0.004), while the association with CM-specific mortality remained non-significant. Overall and melanoma-related costs were higher in melanoma patients with prevalent tumors (overall three-year average costs € 30,698.34 vs. € 17,471.23). Conclusions The presence of prevalent tumors at the time of melanoma diagnosis influences the direct costs associated with healthcare. These findings highlight the significance of integrating multimorbidity considerations into the management and resource allocation in patients with cutaneous melanoma.