Clear cell, papillary and chromophobe renal cell carcinoma in patients younger than 20 years old: a clinicopathologic study with follow-up.

To perform a clinicopathologic study with follow-up on this rare subset of tumors in the pediatric population.A search was made through the surgical pathology files of two academic institutions for cases of non-translocation associated renal cell carcinoma in patients younger than 20 years old from 1995 to 2011.12 cases were identified from 350 pediatric patients with renal tumors (prevalence = 3.4%). The mean age at diagnosis was 11 years (range 1-18 years). The average tumor size was 7.3 cm (range 3.0-15.0 cm). Pathological staging analysis revealed 7/12 (58%) pT1 tumors, 3/12 (25%) pT2 tumors, and 2/12 (17%) pT3 tumors. Lymph node metastasis was present in 3/12 (25%) patients. The majority of tumors 9/12 (75%) were Fuhrman nuclear grade 2, while 3/12 (25%) cases were Fuhrman nuclear grade 3. Tumor necrosis was identified in 5/12 (42%) tumors, and angiolymphatic invasion was identified in 4/12 (33%) tumors; 1 patient developed lung metastasis.Pathologic parameters typically associated with poor outcome in adults, including metastasis/high tumor stage, high Fuhrman nuclear grade, angiolymphatic invasion, and tumor necrosis, did not lead to death in any of the patients in our series.