Clear Cell Sarcoma of the Kidney (CCSK) With BCOR-CCNB3 Fusion: A Rare Case Report With a Brief Review of the Literature

Abstract

Pediatric renal tumors are a rare entity and majority of these tumors are accounted for by Wilms tumor. The second most common renal tumor is clear cell sarcoma of the kidney (CSSK). Most of the CSSK have either BCOR-internal tandem duplication (ITD) or YWHAE-NUTM2B/E fusion. The sarcomas with BCOR-CCNB3 fusion are well documented in soft tissue and bone tumors, but are extremely rare in the pediatric renal setting. We are reporting an extremely rare case of pediatric clear cell sarcoma of the kidney (CSSK) with BCOR-CCNB3 fusion, which was a diagnostic challenge on morphological grounds. A final diagnosis could only be reached after multiple reviews and NGS based RNA fusion testing. We have also performed a brief review of literature which revealed eight (8) other cases of this rare entity.

Limpid and Pellucid- Clear Cell Renal Sarcoma

“…Tumour cells appear immune nonreactive to Wilm's tumour 1(WT1) antigen, CD56, epithelial membrane antigen (EMA), S100 protein, CD99, desmin, carcinoembryonic antigen (CEA), synaptophysin, cytokeratin AE1/ AE3 and CAM5.2. Ki67 proliferative index varies up to 32% [7,8]. Clear cell renal sarcoma requires segregation from renal neoplasms such as clear cell carcinoma, malignant rhabdoid tumour, mesoblastic nephroma or Wilm's tumour [7,8].…”

“…Ki67 proliferative index varies up to 32% [7,8]. Clear cell renal sarcoma requires segregation from renal neoplasms such as clear cell carcinoma, malignant rhabdoid tumour, mesoblastic nephroma or Wilm's tumour [7,8]. Clear cell renal sarcoma may be appropriately treated with total nephrectomy.…”

“…Radiation therapy of dorsolateral thoracolumbar zone appears advantageous. Combination chemotherapy with doxorubicin, vincristine and actinomycin is associated with significant amelioration, wherein doxorubicin is a crucial component which impacts clear cell renal sarcoma with curative intent [7,8]. Inferior prognostic outcomes are observed with stage IV disease and incrimination of paediatric subjects [7,8].…”