Changes in Health Care Costs, Survival, and Time Toxicity in the Era of Immunotherapy and Targeted Systemic Therapy for Melanoma

IMPORTANCE: Melanoma treatment has evolved during the past decade with the adoption of adjuvant and palliative immunotherapy and targeted therapies, with an unclear impact on health care costs and outcomes in routine practice. OBJECTIVE: To examine changes in health care costs, overall survival (OS), and time toxicity associated with primary treatment of melanoma. DESIGN, SETTING, AND PARTICIPANTS: This cohort study assessed a longitudinal, propensity score (PS)–matched, retrospective cohort of residents of Ontario, Canada, aged 20 years or older with stages II to IV cutaneous melanoma identified from the Ontario Cancer Registry from January 1, 2018, to March 31, 2019. A historical comparison cohort was identified from a population-based sample of invasive melanoma cases diagnosed from the Ontario Cancer Registry from January 1, 2007, to December 31, 2012. Data analysis was performed from October 17, 2022, to March 13, 2023. EXPOSURES: Era of melanoma diagnosis (2007-2012 vs 2018-2019). MAIN OUTCOMES AND MEASURES: The primary outcomes were mean per-capita health care and systemic therapy costs (Canadian dollars) during the first year after melanoma diagnosis, time toxicity (days with physical health care contact) within 1 year of initial treatment, and OS. Standardized differences were used to compare costs and time toxicity. Kaplan-Meier methods and Cox proportional hazards regression were used to compare OS among PS-matched cohorts. RESULTS: A PS-matched cohort of 731 patients (mean [SD] age, 67.9 [14.8] years; 437 [59.8%] male) with melanoma from 2018 to 2019 and 731 patients (mean [SD] age, 67.9 [14.4] years; 440 [60.2%] male) from 2007 to 2012 were evaluated. The 2018 to 2019 patients had greater mean (SD) health care (including systemic therapy) costs compared with the 2007 to 2012 patients ($47 886 [$55 176] vs $33 347 [$31 576]), specifically for stage III ($67 108 [$57 226] vs $46 511 [$30 622]) and stage IV disease ($117 450 [$79 272] vs $47 739 [$37 652]). Mean (SD) systemic therapy costs were greater among 2018 to 2019 patients: stage II ($40 823 [$40 621] vs $10 309 [$12 176]), III ($55 699 [$41 181] vs $9764 [$12 771]), and IV disease ($79 358 [$50 442] vs $9318 [$14 986]). Overall survival was greater for the 2018 to 2019 cohort compared with the 2007 to 2012 cohort (3-year OS: 74.2% [95% CI, 70.8%-77.2%] vs 65.8% [95% CI, 62.2%-69.1%], hazard ratio, 0.72 [95% CI, 0.61-0.85]; P