A case report of extensively ossification renal cell carcinoma and review of literature

Objective To review the pathogenesis, pathology, diagnosis and prognosis of calci-fication or ossification renal cell carcinoma with 1 case report. Methods A 48-year-old man was re-ferred for evaluation of an incidental mass found on the upper-middle right kidney, and computed tomography showed a 7 cm tumor with extensively calcification. PET-CT found an extensively calci-fied and ossification mass without high-function in the upper-middle right kidney. Under the diagnosis of renal cell carcinoma, a transabdominal radical right nephrectomy was performed. Results During the operation, a 7.5 crux 5.0 cm well-circumscribed, encapsulated heterogeneous mass was found on the upper-middle right kidney. The patient underwent an partial nephrectomy. Frozen section diagno-sis was renal cell carcinoma with heterotopic bone formation. Then a transabdominal radical right ne-phrectomy plus regional lymph node dissection were performed. Paraffin sections showed renal cell carcinoma with heterotopic bone formation(clear cell carcinoma, pT2b No M0 ). There was neither me-tastasis nor recurrence during the 8 months follow-up. Conclusions Renal cell carcinoma with ossifi-cation is extremely rare. Renal mass with obvious substantive calcification ossification should be trea-ted as malignant mass before operation. The prognosis of renal cell carcinoma associated with ossifica-tion is relatively good. Key words: Carcinoma, renal cell;  Ossification;  Prognosis