Patient characteristics including, age and photodamaged skin, were validated as independent risk factors for keratinocyte carcinoma after allogeneic hematopoietic cell transplantation (alloHCT), according to study results published in JAMA Dermatology.
While it is known that alloHCT increases patient risk for keratinocyte carcinoma, the contribution of patient characteristics to this risk remains unknown; therefore a team of investigators conducted a retrospective cohort study to identify and validate independent risk factors (transplant- and host-associated) for keratinocyte carcinoma after alloHCT.
The primary outcome was time to development of first cutaneous keratinocyte carcinoma following alloHCT. The secondary outcome was time to development of the first individual basal and/or squamous cell carcinoma following alloHCT.
Data from patients who received alloHCT between January 1, 2000, and December 31, 2014, at the Mayo Clinic in Rochester, Minnesota, (872 patients) and the University Hospitals Cleveland Medical Center in Ohio (147 patients) were analyzed.
The team built a multivariate keratinocyte carcinoma risk model based on discovery (581 participants) and validation cohorts (291 participants) from the Mayo Clinic. They validated the risk model using the Mayo Clinic validation cohort, followed by an additional validation using the independent cohort from the University Hospitals Cleveland Medical Center.
The majority of patients from the Mayo Clinic and the University Hospitals Cleveland Medical Center were men (59.6% and 58.5%, respectively) and the average age in each patient population was 48.3 years and 47.9, respectively.
After a follow-up of 5349 person-years, 10.9% alloHCT recipients from the Mayo Clinic cohort developed keratinocyte carcinoma; 12.2% of alloHCT recipients from the external validation cohort developed keratinocyte carcinoma after a follow-up of 880 person-years.
The investigators identified 4 risk factors that were independently associated with keratinocyte carcinoma after alloHCT: age (hazard ratio [HR] per 10 years, 1.72; 95% CI, 1.21-2.42), chronic lymphocytic leukemia (HR, 2.47; 95% CI, 1.20-5.09), clinically photodamaged skin (HR, 3.47; 95% CI, 1.87-6.41), and history of cutaneous squamous cell carcinoma (HR, 2.60; 95% CI, 1.41-5.91).
The concordance (C statistics) for the internal and external validation of the risk model were 0.81 (95% CI, 0.72-0.90) and 0.86 (95% CI, 0.74-0.98), respectively.
Limitations of the study included its retrospective design, limited statistical power, surveillance bias, and limited generalizability.
“These findings highlight the importance of assessing host-associated risk factors for keratinocyte carcinoma in patients eligible for alloHCT,” wrote the authors. “Future studies should examine whether keratinocyte carcinoma risk stratification before alloHCT may inform long-term surveillance strategies.”
Disclosures: Some authors have declared affiliations with the pharmaceutical industry. Please refer to the original study for a full list of disclosures.
Scott JF, Brough KR, Grigoryan KV, et al. Risk factors for keratinocyte carcinoma in recipients of allogeneic hematopoietic cell transplants [published online April 8, 2020]. JAMA Dermatol. doi: 10.1001/jamadermatol.2020.0559