Dr Christine Ko: Transplant Patients Face Unique Skin Cancer Risks

Patients who undergo transplant face an increased risk of skin cancer because of their immunosuppressed status, notably from the medicines they are on to prevent organ rejection, some of which can cause DNA mutations, explained Christine Ko, MD, professor of dermatology and pathology at Yale University.

Transcript

What factors predispose transplant patients to a higher risk of skin cancers?

So I enjoy transplant dermatology because I've been interested for a long time in skin cancer. One of the more common skin cancers they get is reported to be squamous cell carcinoma, which has been a long-standing interest of mine, initially more from the dermatopathology side. So these types of patients, some people are surprised. Some of my friends are like, “Why are you seeing transplant patients?” I reply, “Well, I just look at their skin.” The reason they're at increased risk for skin cancer is because of the immunosuppressive medicines they're on to prevent rejection of the transplanted organ. The great thing is, medicine is continuing to evolve and some of the newer immunosuppressive medicines that they're put on are not as promoting of skin cancer.

So that's great, but for example, azathioprine used to be used more, and that can directly cause mutations in our genetic code, in our DNA. And that's not good. There's a relationship also with sun exposure and sun damage; sun also being able to cause ultraviolet light–induced mutations. And so anything that can sort of add on to that is not good, and azathioprine can do that.

Cyclosporine and tacrolimus are other medicines that are used more often now, compared to azathioprine, and they're both in a class called calcineurin inhibitors. Those medicines don't directly cause DNA damage—like kind of inserting themselves into the DNA the way that azathioprine does—so that's good. But both of those also have strong immunosuppressive effects, which transplant doctors want for the sake and the patient wants too for the sake of their transplanted organ, but [they] can reduce immune surveillance, which is important for preventing skin cancer, particularly in sun-damaged skin of these patients who sometimes have very light skin and a significant amount of sun exposure from the past.