転移性小腸腫瘍の画像診断

Imaging Diagnosis of Metastatic Small Intestinal Tumors

要旨　転移性小腸腫瘍27例について検討した．男性23例，女性4例と男性に多く，年齢は26～72歳，平均年齢は57.2歳であった．原発臓器では，肺癌，悪性黒色腫が多くみられ，原発巣の発見から転移巣発見までの期間は1～74か月（平均13.9か月）であった．転移に伴う症状では下血が最も多く，閉塞（イレウスと腸重積を含む），穿孔と続いた．腫瘍の最大径と症状の間に相関がみられ，小さいうちから閉塞症状を呈して見つかる群と，大きくなっても閉塞を来さず，下血によって初めて見つかる群がみられた．両者の間には病理組織学的にも相違が認められ，閉塞群では強い間質反応または重積の痕跡が認められ，出血群では両者ともに弱い傾向がみられた．形態は，隆起型が約25.9％，潰瘍型が74.1％で，潰瘍型の中では，非狭窄型が全体の約40％と多くみられた．小腸転移が発見された時点で52％に他臓器にも転移を認めており，予後は50％生存期間が3か月と不良であったが，2年以上生存した症例も25％あり，治療法の進歩に伴い小腸転移があっても長期の予後が期待できるようになると考えられた．

　A total of 27 cases with metastatic small intestinal tumors were studied. There were 23 males and 4 females, and the age ranged from 26 to 72 years (average 57.2 years old). As for the origin of metastatic tumors, many of the cases had lung cancer and malignant melanoma. The period from detection of the original tumor to that of the metastatic lesion ranged from one month to 74 months (average 13.9 months). As for clinical manifestations, melena was the most frequent, with obstruction (intestinal obstruction and intususception) and perforation ensuing. A relationship between tumor size and symptoms was found. There was a group of cases which manifested obstruction despite smallness of tumor size and there was another group of cases which did not reveal obstruction despite the largeness of tumor size and which were first detected by melena. There was a histopathological distinction between the groups. In the group presenting obstruction there were marked stromal reactions or signs of intususception, but in the group presenting melena those findings were mild. Morphologically, 25.9％ of the cases were elevated type and 74.1％ were ulcerated type. Approximately 40％ of cases with ulcerated type were non-stenotic type. At the time when metastatic lesions of the small intestine were detected, 52％ of cases had metastasis to other organs, and the prognosis was poor (50％ has survival of only 3 months). However 25％ of cases survived for more then two years, and better prognosis may be expected as better treatment strategies are developed.