The mortality rate for those with Merkel cell carcinoma (MCC) is 40%, similar to the mortality rate for patients with heart failure. Less than 1% of the global population has heart failure, but more than 19% of patients with MCC will die from cardiovascular disease (CVD), according to study findings published in the Journal of the American Academy of Dermatology.
Investigators sought to outline the causes of death associated with MCC. In addition, they aimed to evaluate the incidence of CVD deaths in this patient population and identify patients with MCC at greatest risk for CVD mortality.
They initiated an observational study that included 9375 patients with MCC identified using the Surveillance, Epidemiology, and End Results (SEER) 18 Regs Research Data from 1975 through 2016. Associations between patient and tumor characteristics and cause of death were evaluated using a Cox proportional hazards model. Survival differences for patients who died of MCC vs CVD were examined with a Mann-Whitney U test. CVD mortality derived from the CDC WONDER Online Database was used to create standardized mortality ratios (SMR).
Investigators found the overall median age at MCC diagnosis was 75 to 79 years of age. Among the 3521 patients alive at follow-up, their median age at diagnosis was 70 to 74 years of age. Of the 5815 patients who died during the median 27-month follow-up (median age at diagnosis was 80 to 84 years), they noted that 40.4% of the deaths were attributable to MCC. Other cancers, including hematologic malignancies, lung cancer, and melanoma as the most common, accounted for 17.4% of deaths among patients with MCC.
Investigators found 19.6% of deaths were attributed to CVD, infection (3.3%), cerebrovascular diseases (3.1%), chronic obstructive pulmonary disease (2.7%), and Alzheimer’s disease (2.5%). Median age at death from MCC was 75 to 79 years vs CVD (80 to 84 years), and other causes (75 to 79 years). They calculated that 17 months was the median difference in survival for those who died of CVD (32 months survival; IQR 7-26) and MCC (15 months; IQR 11-73) (P <.001).
They noted that men had a more than doubled increased risk for death due to CVD. They believe a 59% risk reduction is associated with being married. Overall, they found patients with MCC ages 10 to 84 years vs the general population were 8.18 times more like to die of CVD (SMR 95% CI, 8.16-9.48) and 52.8 times more likely to die of all causes (SMR 95% CI, 51.2-54.4).
“The majority of MCC patients died from non-MCC causes,” investigators concluded. They added “CVD mortality was common and occurred at a significantly greater rate than in the general population, with single men at greatest risk.” They urge the importance of age-appropriate screening for CVD and cancers among patients with MCC.
Udkoff J, Russell E, Knackstedt T, Holzer AM. Drivers of overall mortality in Merkel cell carcinoma: a population-based analysis. J Am Acad Dermatol. Published online November 29, 2022. doi:10.1016/j.jaad.2022.11.041