自然脱落をきたした大腸脂肪腫の1例

Lipoma of the Colon That Was Passed Spontaneously, a Case Report

　従来比較的稀と考えられていた大腸脂肪腫も近年その報告例が増加し，わが国では本症例を含め51例が報告されている．今回，われわれは，上行結腸に発生し，本邦第1例目と思われる自然脱落をきたした脂肪腫を経験したので，本邦報告例と併せ検討し，報告する．

　A 45-year-old woman was admitted to the hospital for thorough check-up because she had complaints of epigastric pain since three months before and an abdominal tumor detected by her physician. At admission, an elastic soft tumor with smooth surface suggesting an intestinal loop was palpated in the epigastric region. Laboratory examination showed that the feces was (±) to (＋) for occult blood.

　There was also slight anemia along with accelerated sedimentation rate and slight hypoproteinemia. Barium enema examination of the colon showed in the upper part of the ascending colon a well-defined protrusion with smooth margin. The tumor had a stalk on the oral side. The surface was reticular and no definite ulcer formation was recognized. Barium enema examination done several days later showed that the shadow of the tumor was seen in the descending coion. Air and barium enema, pushing back the tumor successively to the transverse colon and ascending colon, suggested that the tumor was a very mobile pedunculated tumor. Roentgenologically, the tumor also showed changes like “crab's claws” that were suggestive of intestinal intussusception. We had to suspect chronic intussusception as well due to the presence of the tumor. Colonoscopy revealed partial mucosal defect, but except reddening the mucosa covering the surface looked the same as the normal mucosa. These findings were highly suggestive of non-epithelial pedunculated benign tumor. We were ready for ‘surgical intervention, but early in the morning of the day for operation the patient had an episode of severe abdominal pain. Later the patient passed the tumor spontaneously. Histologic diagnosis was an almost oval submucosal lipoma, measuring about 7.0×5.0×4.0 cm. Since 1928, 51 cases of colonic lipoma including the present one have been reported, but we have not as yet come across spontaneous falling-off of lipoma of the colon. The present case must be the first one in Japan. In western coutries according to D’Javid there were only three (1.1 per cent) cases out of 278 reported so far. We have made also reference to the 51 cases of lipoma of the colon reported in this country.