Purpose of review
With the aging population of kidney transplant candidates, a history of malignancy is an increasingly prevalent finding. Tumors can constitute a contraindication for transplantation or can lead to a delay of acceptance to the waiting-list. Current waiting time guidelines mainly refer to early data collected nearly 30 years ago, when the knowledge on tumors was, by current standards, still limited.
Today, cancers can usually be divided into many different biological subtypes, according to histological and molecular subclassification and the availability of genetic testing. A more precise stratification and targeted antitumor therapies have led to better therapy outcomes or even cures from certain malignancies and to a better appreciation of tumor risks for the patient.
Even though transplant patients do have an increased risk for malignancies, it is often overlooked that patients, while on dialysis, are equally prone to develop a tumor. Competing risks (e.g. cardiovascular, mortality risks) through prolonged time on dialysis have to be equally considered, when the decision for acceptance of a patient to the waiting-list is made. Current waiting time suggestions should be critically reconsidered for every patient after a thorough discussion with an oncologist, including new diagnostic and therapeutic strategies, as well as novel risk stratifications.