The Risk of Internal Malignancy Following a Prior Diagnosis of Non-Melanoma Skin Cancer in Solid Organ Transplant...

Solid organ transplant recipients (SOTRs) are at increased risk for both skin and internal malignancies (IM). The risk of IM after the occurrence of non-melanoma skin cancer (NMSC) has been studied in the general population but very little is known about this association in SOTRs.

To evaluate the risk of IM following a prior diagnosis of post transplantation NMSC in SOTRs.

This single center retrospective cohort study included a study population of 329 SOTRs from Rabin Medical Center who had a post-transplant diagnosis of skin malignancy, internal malignancy, or both from 2012 to 2018.

In total, 135 (41.03%) SOTRs were diagnosed with IM without a preceding diagnosis of NMSC while only 42 (12.76%) patients diagnosed with IM had a preceding diagnosis of NMSC. SOTRs with a diagnosis of NMSC showed a significantly decreased risk of developing subsequent IM (hazard ratio [HR] 0.64, 95% confidence interval [95%CI] 0.44-0.94, P = 0.02) compared to those without a prior NMSC diagnosis. Liver and lung transplant patients showed a significantly decreased risk of developing subsequent IM after a diagnosis of NMSC (HR 0.09 and 0.43, respectively). When stratified by type of IM, only patients who were diagnosed with a hematological malignancy had a significantly lower risk of developing this malignancy if they had a prior NMSC (HR 0.26).

The findings of this study suggest a protective effect of NMSC on subsequent IM in the organ transplant population.