Westerman ME, Cheville JC, Lohse CM, et al. - The researchers reported on the long term oncologic outcomes of three subtypes of low grade cystic renal epithelial neoplasms - multilocular cystic neoplasm of low malignant potential (MCLMP), cystic clear cell renal cell carcinoma (ccRCC), and cystic clear cell papillary RCC (ccpRCC), after 2016 reorganization by the World Health Organization. A total of 3,865 individuals, for unilateral, sporadic ccRCC, underwent radical or partial nephrectomy between 1970 and 2010, of which 145 had previously been listed as cystic ccRCC. Of 145 specimens, 18, 95, and 32 were classified as MCLMP, cystic ccRCC, and cystic ccpRCC, respectively. In comparison with those cystic ccRCC and cystic ccpRCC, respectively, those with MCLMP were more likely female with larger tumors. Hardly 2% of cystic ccRCC had tumor necrosis or grade 3 nucleoli present. For survivors, the median follow-up was 10.3 years. During follow up, overall, 1 MCLMP, 5 cystic ccRCC, and 4 ccpRCC reappeared. Across all subtypes, 10- and 20-year cancer-specific survival was 100%. Hence, MCLMP was the least prevalent subtype of low grade cystic renal epithelial neoplasms out of patients who were formerly classified as cystic ccRCC with pathologic re-review and long-term follow-up. Moreover, post-surgical resection, all subtypes were correlated with an outstanding long term prognosis.