Clear cell papillary renal cell carcinoma: a case report and literature review.

Clear cell papillary renal cell carcinoma (CCPRCC), a type of low-grade renal cell neoplasm was recently included in the 2016 WHO classification of renal tumors (Tickoo SK, dePeralta-Venturina Mariza N, Harik LR, Worcester Heath D, Salama ME, Young AN Spectrum of epithelial neoplasms in end-stage renal disease: an experience from 66 tumor bearing kidneys with emphasis on histologic patterns distinct from those in sporadic adult renal neoplasia. Am J Surg Pathol 30:141-153, 2006). While being recognized as its own entity, there is little research on CCPRCC. The specific tumor comprises of 9.3% of all renal tumors in young adults with an age range of 18-88 years (Wang Y, Ding Y, Wang J, Gu M, Wang Z, Qin C Clinical features and survival of clear cell papillary renal cell carcinoma: 10-year retrospective study from two institutions. Oncology letters 16:1010-22, 2018.). In this article we provide recent understanding of CCPRCC and how to identify its distinct pathological entity. It is strongly positive for cytokeratin 7 (CK7), vimentin and mostly negative for CD10 and AMACR (Zhanyong B and John TE Clear cell papillary renal cell carcinoma in bilateral native kidneys after 2 year of renal transplantation: report of a case and review of literature. Case Reports in Transplantation 2011:11-4, 2011). Histopathologically, all cases of CCPRCC exhibited a tubular and papillary architecture, cuboidal tumor cells with clear cytoplasm and low Fuhrman grade (Wang Y, Ding Y, Wang J, Gu M, Wang Z, Qin C Clinical features and survival of clear cell papillary renal cell carcinoma: 10-year retrospective study from two institutions. Oncology letters 16:1010-22, 2018; Kuroda N, Ohe C, Kawakami F, Mikami S, Furuya M, Matsuura K Clear cell papillary renal cell carcinoma: a review. Int J Clin Exp Pathol 7: 7312-18, 2004.; Srigley JR, Delahunt B, Eble JN, Egevad L, Epstein JI, Grignon D, The International Society of Urological Pathology (ISUP) Vancouver Classification of Renal Neoplasia. Am J surg Pathol. 37:1469-89, 2013). This case report and literature review highlights the cryptomorphic, immunohistochemical and cytogenic features of CCPRCC which will assist in understanding and managing these tumors.