Papillary Renal Cell Carcinoma with Clear Cell Change: A Proposed Variant with Unique Morphologic Features
YA Yeh, PR Koduru, C Sreekantaiah, TY Chan. North Shore University Hospital, North Shore-Long Island Jewish Health System and Hofstra University School of Medicine, Manhasset, NY
Background: Papillary renal cell carcinomas are traditionally distinguished from clear cell renal cell carcinomas by their papillary architecture. However, papillary renal cell carcinomas composed of various amounts of neoplastic cells with clear cytoplasm have been observed. Whether these tumors should be classified as papillary renal cell carcinoma or clear cell renal cell carcinoma remains undetermined. We report seven cases of papillary renal cell carcinoma with extensive clear cell change and unique morphologic features.
Design: Seven papillary renal cell carcinomas were retrieved from the slide archives of the Department of Pathology, North Shore University Hospital. Patients included 6 males and 1 female. The age ranged from 51 to 80 years old. Cytogenetics studies were performed.
Results: Seven papillary renal cell carcinomas are composed of solid and papillary patterns of neoplastic cells. Of the seven cases, four tumors show various components of papillary tumors exhibit features typical of type 1 and type 2. Extensive and multifocal clear cell components lining the fibrovascular cores are observed. Clear cells are mostly present in areas of type 2 tumors and are associated with higher nuclear grade. Multiple islands and nests of clear cells are embedded in adjacent stroma with foamy histiocytes and occasional psammoma calcifications. Tumor necrosis and hemorrhage are noted. The table below summarizes our findings.
|Age (yr)||Gender||Cytogenetics||Histologic type||Grade||% Clear cells||Stage|
|1||80||M||+7,+17,-Y,+16||1 +2 (focal)||3||90%, evenly||T1a|
|2||72||F||+7,+17,+16,+20,-3||1 +2 (focal)||3||50%, focal 100||T2|
|3||80||M||+7,+17,-Y,+16,+3||1 +2 (focal)||3||80%, focal 100||T1|
|4||51||M||+7,+17,-Y||1||2||50%, focal 100||T2|
|5||58||M||+7, 9p21 deletion||1 +2 (focal)||2||50%, focal 100||T1|
|6||78||M||+7,+17,-Y,+16,+20||1||2||60%, focal 100||T1a|
|7||71||M||+7||2||1||70%, focal 100||T2|