Renal Adenosarcoma Mimicking a Malignant Pelvocalyceal Tumor: An Interesting Imaging Case.

ABSTRACT: We report a rare case of primary renal adenosarcoma in a 26-year-old woman presenting with right flank pain. Contrast-enhanced computed tomography demonstrated a large, mixed solid and cystic mass confined to the renal pelvocalyceal system, closely mimicking a malignant renal tumor. Histopathologic examination revealed a biphasic tumor with phyllodiform architecture. Immunohistochemistry showed benign epithelial positivity for cytokeratin and focal malignant stromal positivity for smooth muscle actin and CD10; however, the tumor was negative for CD99, Wilm's tumor protein, SS18-SSX, BCOR, and estrogen/progesterone receptors. These findings led to the diagnosis of primary renal adenosarcoma. This case highlights the diagnostic challenge of distinguishing this rare tumor from more common ren

SUBMITTER: Kim SH 

PROVIDER: S-EPMC12896551 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature