Mixed Epithelial and Stromal Tumor (MEST): Case Report of An Unusual Presentation Causing Diagnostic Dilemma

Abstract

ABSTRACT Mixed epithelial and stromal tumor (MEST) are rare tumors of kidney accounting to approximately 0.2 percent of all renal tumors. They have striking female predominance seen in peri-menopausal females. They present as clinically palpable masses hematuria with few being diagnosed incidentally. Most of them are benign with few cases reported with its malignant transformation. We present a case of 41-year-old female who came with the complaints of abnormal uterine bleeding since one and a half years, for which she was further evaluated. Radiology revealed a multiloculated solid-cystic mass lesion in the right kidney with bilateral ovarian cysts which prompted a clinical suspicion of renal neoplasm with metastasis. Right radical nephrectomy revealed a single capsulated solid-cystic tumor. Microscopy was diagnostic of mixed epithelial and stromal tumor (MEST). Due to its rarity, MEST is least suspected clinically. The benign nature of this tumor and its characteristic histopathology leads to accurate diagnosis and appropriate management of patients.