Survivors of childhood cancer at risk of keratinocyte carcinoma

Keratinocyte carcinomas (KC) remain a significant burden among childhood cancer survivors (CCS), but there are predictable risk factors that can guide screening, according to a study.

The authors identified KC among 25,658 participants of the Childhood Cancer Survivor Study, a cohort of 5-year cancer survivors diagnosed <21 years of age between 1970 and 1999 in North America. They estimated the cumulative incidence and generated multivariable models to assess the relative rates of KC associated with survivor and treatment characteristics.

Of the participants, 1,446 developed a total of 5,363 KC (93.5 percent basal cell carcinoma, 6.7 percent squamous cell carcinoma; mean age 37.0 years; mean latency 25.7 years; 95.3 percent White; and 88.4 percent with radiotherapy).

The mean number of lesions was 3.7, with 26.1 percent of patients having at least four. Radiotherapy was associated with a 4.5-fold increase in the rate of any KC and 9.4-fold increase in the rate of ≥4 KC. Likewise, allogeneic and autologous hematopoietic cell transplant correlated with a 3.4- and 2.3-fold higher rate of KC, respectively.

This study was limited by participants’ self-reporting of data, including race without skin phototype and past medical history. This could have influenced the analysis.

“CCS are at increased risk for KC,” the authors said. “[H]owever, the long-term incidence of single and multiple KC is not well established.”