Qap (Anatomical Pathology) 

Case: AP243
Contributor's Comment: Comment: Look for the possibility of Hereditary Leiomyomatosis and Renal Cell Carcinoma (HLRCC) and check for germline mutation of fumarate hydratase gene if indicated. The primary diagnosis would be Type 2 Papillary Renal Cell Carcinoma (RCC). Based on the cytomorphology, the distinction between type 1 and 2 is of important prognostic implication. A numbers of participant also raise the possibility of Xp11.2 translocation RCC. Although the morphology is not typical, but in view of the expanding spectrum of morphology and age range in Xp11.2 translocation RCC , it is reasonable to consider such differential diagnosis.
However, more importantly, for type 2 papillary RCC occurred in young adult, one need to consider the possibility of Hereditary Leiomyomatosis and Renal Cell Carcinoma (HLRCC). HLRCC is an autosomal dominant disease caused by germline mutation of fumarate hydratase. Thus assessing family history and considering testing for germline fumarate hydratase gene mutation would have important counseling and management implications. For this index patient, germline mutation of fumarate hydratase is subsequently confirmed.