According to a new study published in the Journal of the American Society of Nephrology (JASN), patients with certain forms of kidney disease have a reduced risk of developing cancer compared to patients with other kidney diseases. Polycystic kidney (PKD) is a kidney disease characterized by the formation of numerous cysts in the kidney that enlarge the kidney. PKD is thought to have cancer-like features, but the risk of developing cancer has never been compared between people with PKD and people with other kidney diseases. People who receive kidney transplants also have an elevated risk of developing cancer due to immunosuppressive drugs. James B. Wetmore, MD, and his colleagues conducted a study to examine the risk of cancer in PKD kidney transplant recipients compared to other kidney transplant recipients. The team analyzed data from the National Cancer Institute’s Transplant Cancer Match Study, which contains information on all solid organ transplant recipients in the United States, as well as information from 15 population-based U.S. cancer registries. For PKD recipients, the researchers compared their overall cancer risk with that of the general population. They also compared the incidence of cancer in PKD versus non-PKD kidney transplant recipients. The analysis included 10,166 PKD kidney transplant recipients and 107,339 kidney transplant recipients without PKD. After adjusting for differences in demographics between PKD kidney transplant recipients and other recipients, patients with PKD had a 16% lower risk of potentially developing cancer compared to other recipients of kidney transplantation. PKD kidney transplant recipients had a 48% increased risk of cancer overall compared to the general population, while non-PKD kidney transplant recipients had an 86% increased risk of cancer overall. The findings suggest that PKD patients who receive transplants have a lower risk of developing cancer than other kidney transplant recipients. In fact, they may have a lower risk of cancer. The reasons for this are uncertain, but certain factors in the disease itself or factors in PKD patients themselves such as the associated care PKD patients receive are associated with a reduced risk of cancer, Dr. Wetmore said: Further research is needed to determine how PKD may affect the development of cancer. Dr. Wetmore speculates that PKD may induce certain anti-tumor defense mechanisms that prevent subsequent cancer progression. Or it may be that people with PKD often have a progressive medical condition and therefore often receive close medical care for years or decades or engage in other health behaviors to prevent cancer.