Objective Transplantation results in a 5-time elevated risk for a variety of malignancies (Kaposi sarcoma, skin, liver, lung, gastrointestinal cancer). A patient’s risk for malignancies could be of particular interest for the follow-up programs of patients and risk adaption after kidney transplantation. The aim of this study was to identify independent risk factors for de novo malignancies in women after renal transplantation.

Methods and Materials This is a multicenter transversal study, conducted at the Medical University of Vienna and Hospital Rudolfstiftung, Vienna, Austria. We included female kidney graft recipients who were transplanted between 1980 and 2012 and followed-up at our institutions (N = 280). Clinical data of patients were extracted from hospital charts and electronic patient files. Patients were interviewed using a standardized questionnaire regarding their medical history, history of transplantation, and malignant diseases. Detailed information about present and past immunosuppressive regimens, rejection episodes and therapies, renal graft function, and information about primary disease was obtained. Diagnostic work-up and/or surgical exploration was performed if any presence of malignancy was suspected during routine follow-up. Histological specimens were obtained from all patients. Main outcome measures: the presence of de novo malignancy after kidney transplantation.

Results Two hundred sixty-two women were included for statistical analysis. Median (interquartile range) follow-up period after transplantation was 101.1 (27.3–190.7) months. Thirty-two patients (12.2%) developed a malignancy: dermatologic malignancies (5.7%), breast cancer (3.4%), cervical cancer (0.8%), lung cancer (0.4%), gastrointestinal malignancies (1.5%), vulvar cancer (0.4%), and unclassified malignancies (1.9%). Median (interquartile range) time to malignancy after transplantation was 185.9 (92.0–257.6) months. Cumulative cancer rates were 4.9% (1 year), 14.4% (3 years), 16.4% (5 years), and 21.8% (10 years). Second transplantations were identified as independent risk factor for development of malignancy after transplantation.

Conclusions Long-term risk of developing a malignancy after kidney transplantation is high, which might justify a follow-up of more than 10 years.