7) 過誤腫（Peutz-Jeghersポリープ，myoepithelial hamartomaなど）

Hamartoma (Peutz-Jeghers polyp, myoepithelial hamartoma etc.)

要旨　小腸の過誤腫は比較的まれな良性腫瘍である．1995～1999年の5年間に報告された本邦の小腸良性腫瘍196例中，過誤腫は20例（約10％）であり，うち9例はPeutz-Jeghers症候群に合併したものであると報告されている．過誤腫も他の小腸腫瘍と同様に症状を呈することは少ないが，腫瘍が増大すると内腔を狭小化し，閉塞症状を現したり，腸重積による腹痛や出血が主症状となることも多い．診断は小腸造影，CT，腹部超音波検査，出血シンチグラフィー，血管造影検査などを組み合わせて行うことが重要であるが，近年，カプセル内視鏡や小腸内視鏡による診断・治療が積極的に導入されている．

　Hamartomas of the small intestine are benign and rarely detected. During the period from 1995 to 1999, 196 cases of benign tumors of the small intestine were reported. Among them, 20 cases of hamartomas were reported (about 10％) and 9 cases were hamartomas associated with Peutz-Jeghers syndrome. Hamartomas rarely presented abdominal symptoms like other benign tumors in the small intestine. However with increasing size, the lumen of the small intestine becomes small and obstructive symptoms, abdominal pain and bleeding due to intussuception will be presented. Diagnosis is made by the combined use of CT, abdominal ultrasonography, bleeding scintigraphy and angiography. Recently, capsule enteroscopy and balloon enteroscopy have become available and the usefulness of these modalities in the diagnosis and also treatment of benign tumors of the small intestine has been reported.