The multiloculated renal mass: considerations and differential features.

1. Many diverse disease processes may result in a multiloculated renal mass. 2. The term "multilocular cyst" is purely descriptive and should not be used as a specific diagnosis. 3. The management of this diverse group of diseases is controversial. There is insufficient information concerning the accuracy of percutaneous biopsy to permit one to base management decisions on such a biopsy in most of these masses. The cystic diseases (septated cyst, localized cystic disease, segmental multicystic kidney) should be managed conservatively. Most cases of arteriovenous communication are readily diagnosed angiographically and managed by vascular occlusive techniques or by surgery. The remaining multiloculated renal masses usually require surgical removal for histologic diagnosis or definitive therapy or both.