Bifocal clear cell papillary renal cell tumor not associated with end-stage renal disease

Abstract

Clinical case description: A 63-year-old man with gastrointestinal symptoms without history of kidney disease. Through an abdominal computed axial tomography study, two lesions were detected in the right kidney that were resected. By morphology both lesions showed papillary pattern with clear cell features, low grade and fibromuscular stroma. By immunohistochemistry cytokeratin 7, cytokeratin 34βE12, carbonic anhydrase IX, PAX8, parafibromin and vimentin were positive, while CD10, AMARC, RCC, TFE3 were negative.

Clinical implications: Clear cell papillary renal cell tumor (CCPRCT) is a recognized entity that has a unique morphologic and immunohistochemical features with an indolent clinical behavior with no recurrences, metastases or lymph node involvement. It was initially described in conjunction with end-stage renal disease; however, sporadic cases have been described in patients without kidney disease. It is important to correctly differentiate from other subtypes with worse prognosis.

Relevance: CCPRCT previously called carcinoma has changed its name in the latest WHO publication (2022) due to the absence of cases with metastasis or recurrence, it is an indolent neoplasm that must be differentiated from other more aggressive tumors.

Conclusions: CCPRCT can occur in patients without history of renal disease, it has an excellent prognosis, partial or total nephrectomy is the treatment of choice. The pathologist must differentiate it from other renal cell tumors with more aggressive behavior.