Background/aim: Keratinocyte carcinoma (KC) is a marker of increased risk of other cancer types. To assess if this association exhibits a dose-response relationship, a case-control study was carried out.
Patients and methods: This was a clinic-based study of cases with KC plus another type of cancer matched by age, race (all Caucasian), sex and histologic type to controls with KC only (n=48 matched pairs).
Results: Compared with the KC only group, those with KC plus another cancer had a mean number of lesions that were 43%, 35%, and 41% greater for basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and total KC, respectively. The odds ratio (OR) of developing another type of cancer increased from 1.0 to 1.09 (95% confidence interval (CI)=0.23-5.13) to 2.12 (95%CI=0.50-9.08) according to whether the patient had zero, one, or ≥two BCC lesions; for SCC, the corresponding ORs were 1.0, 1.24 (95%CI=0.48-3.24), and 1.39 (95%CI=0.29-6.61).
Conclusion: A dose-response relationship seems to exist between the number of skin lesions and the risk of another type of cancer, but the lack of statistical significance weakens this evidence.
Keywords: Keratinocyte carcinoma; cancer risk; case-control study; epidemiology; nonmelanoma skin cancer; second primary cancers.
Copyright© 2019, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.