Clear cell sarcoma of the kidney in children: a clinopathologic analysis of three cases.

BACKGROUND Clear cell sarcoma of the kidney (CCSK) is a rare malignant tumor in children with uncertain histologic and immunohistologic traits. It mostly reveals atypical clinical symptoms similar to other familiar pediatric renal neoplasms, including abdominal mass, abdominal pain, hematuria, etc. Therefore, the lack of specificity in clinical symptoms may induce some challenging and controversial diagnoses. METHODS Three cases of CCSK were acquired data from the First Affiliated Hospital of Bengbu Medical College (China) in recent years, accompanied by clinical symptoms and imaging manifestations without obvious specificity, while abdominal mass and abdominal pain were described as the main manifestations; even the initial clinical diagnosis of one case was Wilms Tumor (WT). Two of them underwent a radical nephrectomy. All 3 cases were detected by hematoxylin-eosin (H&E) staining and immunohistochemistry. RESULTS Microscopic examination demonstrated the tumor component consisted of loose, locally dense tumor stroma and parenchyma composed of round or oval cells, which were separated by dendritic fibrosis. Afterwards, the unified immunophenotype were positive for Cyclin D1, Bcl-2, Vimentin, SATB-2, α-AACT, and Ki-67 (+, 30%, 40% and 80%, respectively). CONCLUSION Pathologic diagnosis of the disease should be comprehensively analyzed by multiple methods. More abundant morphologic, immunohistological, clinical and radiologic data can contribute to rigorous diagnosis and more accurate clinical treatment.