Westerman ME, et al. - Following 2016 reorganization by the World Health Organization, researchers examined three subtypes of low grade cystic renal epithelial neoplasms—multilocular cystic neoplasm of low malignant potential (MCLMP), cystic clear cell RCC (ccRCC), and cystic clear cell papillary RCC (ccpRCC)— regarding their long-term oncologic outcomes. Among the 3,865 patients who underwent radical or partial nephrectomy for unilateral, sporadic ccRCC from 1970 to 2010, there were 145 who had previously been classified as cystic ccRCC. Rereview and reclassification of the specimens by 2016 WHO criteria was performed by one genitourinary pathologist who was blinded to outcome. Classification of 145 specimens determined 18 (12%) as MCLMP, 95 (66%) as cystic ccRCC, and 32 (22%) as cystic ccpRCC. Those with MCLMP were most likely to be female and have larger tumors; this was also the least common of the subtypes of low grade cystic renal epithelial neoplasms. Outcomes revealed that surgical resection results in excellent long-term prognosis in correlation to all subtypes. Across all subtypes, 10- and 20-year cancer-specific survival was 100%.