転移巣が先行して発見された胃原発転移性大腸癌の1例

Colonic Metastasis from Gastric Cancer Discovered Earlier than the Primary Lesion, Report of a Case

要旨●患者は60歳代，女性．主訴は腹部膨満感，便秘，腹痛，嘔吐．注腸X線造影検査，大腸内視鏡検査で肝彎曲部・横行結腸の狭窄，横行結腸上縁・下行結腸内側を中心に顆粒状粘膜と片側性変形を認めた．上部消化管X線造影検査・内視鏡検査で胃壁の伸展不良を認め，小腸X線造影検査では中部〜下部小腸に片側性変形，狭窄を認めた．横行結腸と胃から採取した生検組織の粘膜固有層内に低分化腺癌および印環細胞癌のびまん性増殖がみられ，免疫組織化学染色ではCK（cytokeratin）7陽性，CK20陰性であった．以上より，胃を原発とした低分化腺癌および印環細胞癌が大腸・小腸に転移を来した症例と診断した．

　A 60s woman was admitted to our facility with complaints of constipation, abdominal pain, fullness, and vomiting. Barium enema and colonoscopy revealed hepatic flexure and transverse colon stenosis, granular mucosa from the proximal colon to the sigmoid-descending junction, and eccentric stenosis in the transverse and descending colon. Upper gastrointestinal radiography and esophagogastroduodenoscopy revealed that the gastric wall was not distensible. Small bowel radiography revealed unusual stenoses. Biopsy specimens from the stomach and colon were histologically examined, which revealed poorly differentiated adenocarcinoma and signet-ring cell carcinoma in the gastric and colonic lamina propria. Both tumor cells were immunohistochemically positive for CK（cytokeratin）7 and negative for CK 20. We diagnosed the patient with colonic and small intestinal metastases from primary gastric cancer based on the abovementioned radiographic and endoscopic findings as well as the CK7（＋）/CK20（−）pattern.