Supplemental Files for "The incidence of keratinocyte carcinomas accelerates before the end of life""

This study investigated whether increases in keratinocyte carcinomas (KC) could serve as a marker of impending death. Using a large international patient database, patients with a history of KC who died in 2023 were compared to matched survivors, revealing that squamous cell carcinoma (SCC) diagnoses progressively increased before death while basal cell carcinoma diagnoses showed an initial rise followed by a decline. A sensitivity analysis from 2015-2019 only supported these patterns for SCC and benign neoplasms, suggesting that the COVID-19 pandemic may underlie some of the variation seen in BCC diagnoses. These patterns, along with a decrease in benign skin neoplasm diagnoses, suggest that both biological changes in aging skin and altered healthcare-seeking behavior may underlie these observations. Rising SCC incidence in the absence of known risk factors could help identify high-risk patients nearing the end of life.