A Calcifying Fibrous Tumor Which Developed in the Small Intestine Causing Ileus

We present a case of a calcifying fibrous tumor (CFT) in the small intestine causing ileus. To the best of our knowledge, CFTs occurring in the small intestine are extremely rare. A 69-year-old man presented with abdominal pain. Abdominal CT and US showed a calcified nodule measuring 1 cm in diameter adjacent to a sharp U-shaped bend in the small intestine where the caliber of the small intestine changed. Failure of intestinal decompression with a long tube indicated the need for surgical intervention. At laparotomy, the U-shaped bend caused bowel obstruction, and the patient underwent resection of the affected small intestine. Histopathologically, the lesion was a smooth, marginated, hyalinized nodule measuring 1 cm in diameter with accompanying calcification located in the muscular layer of the small intestine. Immunohistochemically, spindle cells identified in the nodule were positive for vimentin and CD34 and negative for α-SMA, desmin, S100, CD117 and ALK. Therefore, we diagnosed the nodule as CFT.