RESUMO
A-49-year-old man was admitted because of a lower abdominal mass. During the five days prior to admission, he had noted fever and lower abdominal pain. Palpation of the abdomen revealed a tender mass, 10 cm in diameter, in the suprapubic region. An x-ray revealed an irregular collection of gas, 9 cm in diameter, in the pelvic cavity, which appeared as a mirror image when the patient was upright. Based on the physical finding and the results of a barium enema, abdominal CT, MRI, and small intestine imaging, a diagnosis of leiomyosarcoma of the ileum was made. Excision of the tumor and part of the small intestine was performed. A saccular tumor, 11 x 6 x 5 cm, was found 1.0 m from the cecum and growing out of the wall of the ileum. A large amount of pus was found inside the cavity. The pathological diagnosis was leiomyosarcoma.