Pathological features and outcomes of incidental renal cell carcinoma in candidate solid organ donors

Background: We report the findings of a single Italian center in the evaluation of renal lesions in deceased donors from 2001 to 2017. In risk evaluation, we applied the current Italian guidelines, which include donors with small (< 4 cm, stage pT1a) renal carcinomas in the category of non-standard donors with a negligible risk of cancer transmission. Methods: From the revision of our registries, 2,406 donors were considered in the Emilia Romagna region of Italy; organs were accepted from 1,321 individuals for a total of 3,406 organs. Results: The evaluation of donor safety required frozen section analysis for 51 donors, in which a renal suspicious lesion was detected by ultrasound. Thirty-two primary renal tumors were finally diagnosed: 26 identified by frozen sections and 6 in discarded kidneys. The 32 tumors included 13 clear cell renal cell carcinomas (RCCs), 6 papillary RCCs, 6 angiomyolipomas, 5 oncocytomas, 1 chromophobe RCC, and 1 papillary adenoma. No cases of tumor transmission were recorded in follow-up of the recipients. Conclusion: Donors with small RCCs can be accepted to increase the donor pool. Collaboration in a multidisciplinary setting is fundamental to accurately evaluate donor candidate risk assessment and to improve standardized protocols for surgeons and pathologists.