1287 Keratinocyte carcinomas in skin of color patients: A cohort study

Keratinocyte carcinoma (KC), comprised of squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), is the most common cancer in the United States (US). KCs occur most commonly in Caucasian patients. Little has been reported on the demographics and incidences of KCs in patients with SOC. We aimed to investigate KCs in SOC patients using a large claims dataset. We performed a retrospective cohort study using a de-identified, random sample of 4,999,999 fee-for-service Medicare beneficiaries (2009-2018). We included those with at least one surgically treated KC, defined by at least one ICD code for KC diagnosis and at least 1 CPT code for KC treatment on the same date. We evaluated demographics, incidences and anatomic locations of KCs in Caucasians and SOC patients. We defined SOC patients as Black, Other, Asian, Hispanic, or North American Native. We identified 784,880 patients with at least one surgically treated KC: 766,227 (97.6%) were Caucasian and 18,653 (2.4%) were SOC patients. SOC patients were more likely to be female (55% vs 51%, p<0.001) and older at first KC diagnosis (77.7 vs 76.7, p<0.001). We identified 2,498,805 KCs: 2,455,090 (98%) in Caucasians and 43,715 (2%) in SOC patients. The age adjusted incidence rate of KCs was 11,488 per 100,000 person-years in Caucasians and 1,196 per 100,000 person-years in SOC patients. The anatomic locations of KCs were similar in Caucasian and SOC patients: most common were head and neck (Caucasians 54%, SOC 59%, p<0.001) and upper limb (Caucasians 18%, SOC 16%, p<0.001). Greater proportions of KCs on the head and neck in SOC patients were driven by KCs on the face (4-9% absolute higher numbers of KCs on the face in SOC patients, p<0.001). Understanding incidences and anatomic sites of KCs in SOC patients is vital to addressing gaps in diagnosis and management for SOC patients.