連続した3つの病変からなる胃小細胞癌の1例

Small Cell Carcinoma of the Stomach, Report of a Case

要旨　患者は69歳，男性．食欲低下と嘔気を訴えて当院を紹介された．胃X線，内視鏡検査では，胃体部小彎から前庭部の前後壁にかけて大きな腫瘤が認められた．この腫瘤は連続したBorrmann 1型様の隆起と，2個のBorrmann 2型様の病変とから成り立っていた．これらの臨床的所見，および生検組織診の結果から，胃悪性リンパ腫と診断され，胃亜全摘術が施行された．切除標本の病理組織学的検索では，類円形または紡錘形の核を有する胞体の乏しい腫瘍細胞が不規則に増殖して認められ，一部に偽ロゼット構造や索状配列を示すことから，胃小細胞癌と診断された．患者は，術後54日目ごろから感冒様症状が出現し，術後63日目に広範な肺転移による呼吸不全で死亡した．胃小細胞癌の邦人による報告例は，検索しえた範囲では本症例を含めわずか7例である．その組織発生について文献的に考察を加え報告した．

　The patient was a 69-year-old male who was referred to our hospital because of vomiting and loss of appetite. Gastric radiography and endoscopy demonstrated a large tumor extending from the lesser curvature of the middle body to the anterior and posterior walls of the antrum. The tumor had a massive Borrmann 1-like elevation 〔lesion 1〕 and two Borrmann 2-like lesions 〔lesion 2, 3〕. These findings and results of biopsy examinations led to the preoperative diagnosis of malignant lymphoma and subtotal gastrectomy was carried out. Histopathologic examination of the resected specimen showed irregular proliferation of tumor cells with little cytoplasm and round or spindle-shaped nuclei, and part of tumor cells forming a pseudo-rosette structure and trabecular disposition, and thereby leading to the final diagnosis of small cell carcinoma. The patient developed flu-like symptoms on about 54th postoperative day and died of diffuse metastasis to the lung on the 63rd postoperative day.

　Our literature survey indicated that this case is the 7th case of small cell carcinoma of the stomach in Japan. Histogenesis of small cell carcinoma of the stomach remains to be clarified in the future.