RESUMO
Multilocular cystic renal cell carcinoma [MCRCC] is a rare clear cell type of renal cell carcinoma. Although cytologyically and cytogenetically MCRCC is similar to clear cell carcinoma, histology and behavior differ markedly. Prognosis in MCRCC is excellent as the tumour is of consistently low grade and surgical resection is curative. We report here a case of MCRCC in 44 year old female presented with right loin pain, was miss-diagnosed as renal hydatid cyst for 2 years. Local excision of the tumor mass only was done with no recurrence after 30 months of follow up after. The differentiation between renal hydatid cyst and MCRCC may be difficult clinically and radiologically.The tumor grows very slowly.The outcome of the lesion is not affected adversely by large tumor size. There is an increasing belief that MCRCC should be renamed and reclassified to indicate much more favorable prognosis than the conventional clear renal cell carcinoma