Immunosenescence markers as predictors of cutaneous keratinocyte carcinoma risk in heart transplant recipients: a prospective pilot study of 30 patients

Cutaneous keratinocyte carcinomas (CKCs) are more frequent and aggressive in solid organ transplant recipients (SOTRs), particularly heart transplant recipients (HTRs), owing to prolonged immunosuppressive treatment. This prospective cohort study evaluated the association between immunosenescence markers and CKC development in 30 HTRs over 1 year of follow-up. Lymphocyte subpopulations were analyzed by flow cytometry, along with cellular immunosenescence markers including PD-1, CD57, and TIGIT. At the end of follow-up, 23.3% of patients developed new CKCs. These patients showed a higher proportion of CD8⁺PD-1⁺ lymphocytes compared to those without new CKCs. No significant differences were found in CD4⁺ lymphocyte populations, NK cells, or regulatory T cells. These results suggest that CD8⁺PD-1⁺ lymphocytes may represent a potential biomarker associated with increased CKC risk in HTRs.