Clear cell papillary renal cell carcinoma : two cases report and review of literature

ZENG Ying; MA Qiang; ZHONG Peng; DU Juan; MA Yu; LIN Li; FU Ping; XIAO Hua-liang

doi:10.3969/j.issn.1007-8096.2018.03.004

Abstract：To investigate clinicopathologic features and differential diagnosis of clear cell papillary renal cell carcinoma ccpRCC).Methods The clinical and radiological data were collected in two cases of ccpRCC,their pathological and immunohistochemical features,pathological diagnosis and differential diagnosis were studied with review of related literature.Results The age of the patients at diagnosis was 37 and 50 years,respectively one ease was male and one female.The one lesion was located in the left kidney,and one lesion was located in the right kidney.Clinical manifestation of one patient was back pain for half an year,and one patient was detected in physical examination.The two lesions were solid.Histologically,the tumors were encapsulated and showed several morphologic patterns,with macro/microcysts,tubules,papillae,acini,interconnecting ribbons lined by single layer of cells with clear cytoplasm and low-grade nuclei (WHO/ISUP nuclei grade 1 or 2).Characteristically,there was linear arrangement of the nuclei away from the basement membrane.The results of immunohistochemistry showed that CK7,CK34betaE12,vimentin,EMA,MOC31,PAX-2,PAX-8 were positive,CAIX was with characteristic " goblet" staining pattern.CD117,P504S,E-cad,p53 and TEF-3 were negative,and Ki-67 proliferation index was 2％.The two patients were disease-free after operation.Conclusion ccpRCC is a rare variant of RCC and has a favorable prognosis.Differential diagnosis includes clear cell renal cell carcinoma,papillary renal cell carcinoma,multilocular cystic renal neoplasm of low malignant potential.The diagnosis should be combined with histopathological and immunohistochemical phenotype.