著明な間質反応を伴った胃のいわゆる癌肉腫の1例

A Case of the So-called Carcinosarcoma associated with Prominent Stromal Reaction

　胃に発生する癌肉腫は稀な疾患である．著者らがここに報告するものは肉眼的にはBorrmannⅡ型進行胃癌が疑われたが，組織学的に著明な間質反応を伴う腫瘍であって，これを癌肉腫とすべきか，肉腫様形態を伴う異型的な癌腫とすべきか判断に迷うものである．元来，癌肉腫のentityに関しては諸家により見解を異にし，その存在自体を疑うものも多いが，本症例の特異な組織像より著者らは“いわゆる癌肉腫”として報告する．

症例

　患　者：63歳　男性

　主　訴：心窩部重圧感

　家族歴：父（43歳）と母（80歳）共に胃癌で死亡．同胞5人には特記事項なし．

　現病歴：約20年前より某院で便秘のため冶療を受けていた．1970年8月30日，心窩部に重圧感および膨満感があり是真会東望病院を訪れたが，心窩部痛，胸やけ，嘔気その他の消化器症状はなかった．同年9月1日，胃X線検査を受け前庭部小彎に巨大潰瘍があり穿通性胃潰瘍を疑われ同院に入院した．

　入院時現症：体格大，栄養状態良好．眼瞼結膜に貧血なく，眼球結膜に黄疸なし，脈拍80整，緊張良好，血圧130/70．口腔および咽頭に著変なく，舌苔厚し．頸部リンパ節腫脹なし．心肺に理学的所見なし．腹部は平坦．軟で圧痛，抵抗もなく腫瘤触知せず．肝，脾，腎はともに触知せず．下肢に浮腫なく腱反射正常で病的反射なし．

　Carcinosarcoma originating in the stomach is a rare disease. Opinion differs about its entity. There are many like Saphir who doubt its presence itself.

　A 63-year-old man visited us with a chief complaint of feeling of pressure in the epigastrium. As both x-ray and endoscopy suggested cancer, operation was performed. The resected stomach showed a tumor on the lesser curvature of the pyloric antrum associated with a large ulceration over it. The neoplasm reached the muscular coat in cut section. Histologically, tumor cells with monotonous sarcoma-like structure proliferated especially in the middle and lower layers of the tumor. Poorly differentiated tubular carcinoma was seen in the upper layers with a shifting change to sarcoma-like cells in between. In a part of the mucosa around the ulcer was seen highly differentiated tubular carcinoma, suggesting its link to the afore-mentioned carcinomatous part.

　These results may be construed as showing atypical carcinoma with more of sarcomatous picture than well differentiated carcinoma, but we arrived at a diagnosis of “the so-called Carcinosarcoma” on account of the peculiar histologic picture of sarcoma-like cells.

　Stromal reaction was recognized in the lower layers of the tumor as well as in the adjacent region, surrounding, as it were, the tumor. In spite of its large size, the tumor was localized with no lymph node metastasis. As of this writing, more than 5 years after the operation no recurrence is seen. Stromal reaction may play a part in prognosis.