The eyes don't see, what the mind doesn't know

Abstract

Abstract Introduction/Objective Calcifying fibrous tumor is a rare benign mesenchymal neoplasm. The etiology and pathogenesis of this tumor are uncertain. It has wide anatomical distribution. The tumor is most commonly found in the soft tissues of the extremities in younger individuals. However, in middle aged patients it tends to affect the visceral locations more commonly. In visceral location it can mimic aggressive lesions clinically. The purpose of this report is to describe a case of calcifying fibrous tumor in a 71-year-old female with a history of breast carcinoma who was found to have an incidental small bowel mass on her follow up. Clinically and radiologically and the main diagnostic consideration were metastatic disease and gastrointestinal stromal tumor. Methods/Case Report The patient underwent an open small bowel resection, and a 6.5 cm segment of small bowel was sent to pathology. Grossly, a 2.0 cm tan-pink smooth round submucosal polyploid mass protruding into the lumen, mimicking gastrointestinal stromal tumor was identified. The tumor was hard and serially sectioned to reveal a white, calcified cut surface. Microscopically, the tumor appeared hypocellular and composed of scant spindle cells embedded in a dense, hyalinized and calcified, collagenous stroma. Immunohistochemical stains for pan cytokeratin, DOG1, desmin, S100, CD34, and MUC4 were negative, and diagnosis of calcifying fibrous tumor was rendered. Results (if a Case Study enter NA) NA. Conclusion This case highlights the importance of knowledge of rare entities in providing accurate diagnosis for lesions that can clinically mimic common tumors.