People receiving liver transplants are at higher risk for non-Hodgkin's lymphoma and colorectal cancer, according to a recent Canadian study published in Liver Transplantation.

Past studies have shown that the drugs used to help bodies accept new liver transplants, in addition to the transplantation process itself, lead to an increased cancer risk in recipients.

In an effort to advance previous research, officials at the Public Health Agency of Canada used the Canadian Organ Replacement Registry to cross-reference liver transplant recipients with national mortality and cancer incidence databases.

The researchers focused on more than 2,000 patients who received a transplant between June 1983 and October 1998. The health history of these patients was followed for up to 15 years.

The study excluded patients who already had liver cancer or who had been diagnosed with any other type of cancer, excluding non-melanoma skin cancer, before transplantation, or in the following 30 days.

According to the report, researchers were astounded by the higher incidents of non-Hodgkin's lymphoma, with an approximate 20-fold increase compared to the general population.

The second highest disease reported was colorectal cancer, which researchers thought could be attributed to the higher instances of inflammatory bowel disease in liver transplant recipients. Cancer risk in general was more likely during the first year of follow up.

Authors of the study recommend more surveillance and screenings for liver recipients.