Various Histological Types of Renal Cell Carcinoma Associated With Hereditary Papillary Renal Cell Carcinoma (HPRCC): a Case Report

Abstract Background: Hereditary papillary renal cell carcinoma (HPRCC) is a rare autosomal dominant disease characterized by the development of multiple and bilateral papillary type I renal cell carcinomas (RCC) and papillary adenomas caused by activating mutations in the MET proto-oncogene. Classically, distinctive histological features of RCC are described according to the familial renal cell carcinoma syndrome. To date, no clear cell RCC has been reported in HPRCC syndrome. Case presentation: We describe the case of a 51-year-old man with a germline MET mutation, who developed numerous papillary tumors but also unexpectedly clear cell renal cell carcinomas. During the follow-up, an adrenal metastasis was observed seven years after the initial diagnosis corresponding to a clear cell RCC metastasis. Using FISH, the metastatic tumor presented a trisomy of chromosomes 7 and 17. These genomic alterations are usually detected in papillary RCC, highlighting the potential link between both histological subtypes of tumors and the HPRCC syndrome.Conclusions: The pathologist must be aware that the presence of a non-papillary RCC associated with numerous papillary tumors should not exclude the diagnostic suspicion of HPRCC and thus to perform a thorough genomic study.