“…2,6 The majority of cysts are benign, acquired, and soli-( In most series with histologic follow-up, radiographically suspicious cysts almost always prove to be RCC. 4,7,10 Finally, in the largest series of cystic RCCs to date (11 cases), only 2 cases had atypical cells on cytologic examination, and repeated aspirates in these 2 patients were negative. 44 This strongly suggests that the sensitivity of FNA for the diagnosis of cystic RCC is low, and will remain so despite attempts to thoroughly sample the edge of radiographically cystic lesions.…”