Background/aims: The increasing length of survival of organ transplant recipients necessitates careful attention to the potential neoplastic complications of life-long immunosuppression, which is required for such patients. Previous studies by Penn of patients taking triple drug therapy (Cyclosporin, Azathioprine and Prednisone) for immunosuppression, or even of those taking Imuran and Cyclophosphamide, have shown a high percentage of tumor development (3117 per 2915 patients).
Methodology: Three thousand three hundred and ninety-four adult patients underwent orthotopic liver transplantation (OLTx) at the University of Pittsburgh Medical Center, Transplant Institute prior to December, 1992. Of these, 1657 were examined (48.8%). All patients with hepatic or biliary cancer as the indication for OLTx were excluded; all other indications were considered. All forms of tumor development after OLTx were considered, except for lymphoprolipherative disease and hepato-biliary tumors. The immunosuppressive regimens were reviewed and patients treated with FK 506 and Cyclosporin A (CSA), as well as those switched from CSA to FK 506, were divided into different groups.
Results: A total of 50 patients with tumors were identified (37 males, 13 females), ranging between 34 and 69 years of age. Of these patients, 48 are still alive. In these patients, 64 tumors, classified according to the TMN classification, were discovered: 50 in males and 14 in females. Two metastases were found following discovery of the tumor. The tumors identified were as follows: basalioma 25%, squamous 20.3%, Bowen 6.2%, warts 3.1%, melanoma 6.2%, Kaposi's sarcoma 3.1%, colonic adenocarcinoma 3.1%, colonic polyps 4.6%, rectal cancer 1.5%, breast cancer 4.6%, cervical cancer 3.1%, ovarian cancer 3.1%, laryngeal cancer 3.1%, prostate cancer 1.5%, lung cancer 3.1%, gastric cancer 3.1%, and hemangioblastoma 1.5%.
Conclusions: Skin cancer is the most common type of tumor discovered after liver transplantation (The transplant does not change the occurrence in lung transplants with a positive smoking history). A lower incidence of tumors was found after liver transplantation as compared to kidney transplantation. A higher incidence of tumors was found with CSA, as opposed to FK 506 immunosuppression therapy. None of the patients in this series experienced acute graft rejection necessitating re-transplantation. Chronic graft rejection was treated either with FK 506 or with OKT3, without an increase in the incidence of tumor development.