転移性小腸腫瘍のX線診断

Radiologic Diagnosis of Metastatic Tumors of the Small Intestine

要旨　過去28年間に国立がんセンター病院で外科的に切除された転移性の小腸腫瘍129例について検討した．その90.7％は原発巣が腹部の臓器由来で，9.3％は腹部以外の悪性腫瘍からの転移であった．転移性の小腸腫瘍のX線像には，胃，小腸，結腸の問に共通性がみられた．すなわち腹部臓器由来の悪性腫瘍，特に腺癌が小腸壁に浸潤・転移した場合は，病変の主体は漿膜側にあって，X線像では，腸管の長軸方向に幅が数mm大の粘膜ひだの収束像が特徴的な所見であった．次に，腹部の臓器以外の悪性腫瘍が，小腸壁に脈管性に転移し切除された例は12例で，そのうちの10例は肺癌からの転移であった．そこで，今まであまり知られていない肺癌からの転移性小腸腫瘍を主体に，その臨床的事項，切除標本の肉眼像，X線像における特徴像について検討した．その結果，肺癌からの転移性小腸腫瘍の特徴として，①男性に多い，②多発傾向がある，③空腸に多い，④大細胞癌が多い，⑤イレウス，穿孔，出血が主な症状である，⑥発育形式と時期によって，腫瘤型，扁平隆起型，隆起陥凹型，陥凹型，を示す，⑦悪性リンパ腫，小腸癌，平滑筋肉腫，カルチノイドとの鑑別診断が必要となることを述べた．

　The purpose of this paper is to analyze macroscopic and radiologic features of 129 cases of metastatic small intestinal tumors which were resected surgically at the National Cancer Center Hospital over the last 28 years. In 90.7% of cases, primary lesions were found in the abdomen, with extra-abdominal primary lesions accounting for the remainder. Metastatic small intestinal tumors from stomach, small and large intestinal primaries had common pathological and radiologic features: they were typically adenocarcinoma and were principally located on the serosal side of the intestinal wall. X-ray examinations revealed mucosal fold convergence, several mm in width, aligned in a longitudinal direction. Small intestinal metastasis of extra-abdominal origin were thought to be hematogenous. Ten out of the 12 cases of extradominal origin were lung cancer. We focused on clinical, macroscopic and radiologic features of metastatic small intestinal tumors from lung: 1) male sex was dominant, 2) multiple lesions were noted, 3) jejunum was more prone to be involved than ileum, 4) giant cell cancer was the common histological type, 5) common clinical presentations were ileus, perforation, and bleeding, 6) the shapes of tumor were classified as mass-forming, flat but elevated, flat and depressed, and depressed depending on the stage and the pattern of growth, and 7) differential diagnosis included malignant lymphoma, primary small intestinal cancer, leiomyosarcoma, and carcinoid.