Organ transplant recipients face an elevated risk of keratinocyte cancers (KCs) due to immunosuppression. Although many studies have focused on the increased incidence of KC in solid organ transplant recipients (SOTR), the burden of disease directly relates to the number of skin cancers requiring therapy. This retrospective cohort study conducted from 2017 to 2021 in Brisbane, Australia, aimed to evaluate trends in KC numbers among kidney and lung transplant recipients while identifying patient predictors and modifiable clinical practices to alleviate the burden of KCs.
240 patients were enrolled in the study. Over the 5 years of investigation, a total of 2384 KC (all histology proven) were excised. Among all patients, prevalence ratio increased by 28% in 2021 compared to 2017 (p=0.005). In average, the number of KC per patient rose from 2.3 in 2017 to 2.9 in 2021 (p=0.006). However these changes in KC numbers were not homogenous across the population. When focusing only on data obtained at least 12 months post-transplantation for 3 consecutive years (n=189), we could identify 5 clusters reflecting evolution trends in KC numbers: decreasing (11%), increasing (32%), stable-low (24%), stable high (11%), increase-then decrease (7%), excluding those with no KC across the 5 years (15%). Age, transplant type, use of chemoprophylaxis and occupational sun exposure were significantly associated with specific trends in KC numbers.
Overall, SOTRs experience different trends in their number of KC over time. Understanding drivers of increase or decrease in numbers of KC will help in the management of his life-threatening complication.