電腦斷層攝影對胃平滑肌腫瘤之診斷

Computed Tomography of Gastric Smooth Muscle Tumor

潘慧本(HB Pan) ； 姜仁惠(JH Chiang) ； 刁翠美(CM Tiu) ； 周宜宏(YH Chou) ； 郭萬祐(WY Guo) ； 張遵(T Chang) ； 蔡養德(YT Tsai) ； 雷永耀(WY Lui)

《中華放射線醫學雜誌》 11卷4期 (1986/12) Pp. 291-298

摘要

榮民總醫院自民國69年初至民國75年初，6年間有21名接受CT掃描和手術切除而經病理證實為胃平滑肌腫瘤的病例；其中平滑肌瘤8名、平滑肌肉瘤12名、平滑肌母細胞瘤1名；男性14名、女性7名。年齡分佈自36歲至77歲，平均55.7歲。CT測量最大橫徑＜10公分的腫瘤，71%屬於良性。50%平滑肌瘤以均勻密度表現，而體積較大之良性腫瘤及所有惡性腫瘤都有壞死現象。中心性壞死(24%)全發生於平滑肌肉瘤病例，且在距離原發腫瘤愈遠方之腫瘤部分，壞死程度愈嚴重。僅有1例在腫瘤之中心部有鈣化現象。靜脈注射顯影劑能使此種含血管豐富的平滑肌腫瘤之實質部加強顯影；以口服顯影劑或水為對比劑對胃部平滑肌腫瘤之診斷各有優劣。9例平滑肌腫瘤直接侵犯附近器官(43%)；2例藉著播種(seeding)或腹水轉移至腹腔及骨盆腔內；1例有肝臟轉移：淋巴轉移較為罕見(4.8%)。腫瘤為外生性(exophyted)而且壞死佔大部份時需與附近器官特別是胰臟之囊樣腫塊作鑑別診斷；胃潰瘍(43%)或瘻管(19%)之存在有助於平滑肌腫瘤之確認，但仍需與其他胃腫瘤區分。胃平滑肌腫瘤不能繞胃腔一周，此點與小腸平滑肌腫瘤不同。

並列摘要

Twenty-one patients with gastric smooth muscle tumor, undergone computed tomography (CT), were proved surgically and pathologically within the recent six years in the Veterans General Hospital, Taipei. These included 14 male and 7 female. The age ranged from 36 to 77 years old with an average of 55.7. Eight patients had leiomyoma, 12 leiomyosarcoma and 1 leiomyoblastoma. CT shows that 71% of benign leiomyoma has a greatest transverse diameter within 10 cm. And half of them have a homogeneous density. Necrosis is usually present in the malignant tumor and huge benign tumor. Central necrosis (24%) is rather specific for leiomyosarcoma which takes place more easily in the periphery of the main tumor. Only one tumor shows calcification in its center.
Intravenous contrast material usually shows good enhancement to these tumors since they are hypervascular. Oral contrast ingestion or water intake has equivocal results in diagnosing gastric smooth muscle tumor. Direct invasion of tumor to the adjacent organs are noted in 9 patients (43%), 2 cases show presence of peritoneal seeding and 1 case (4.8%) metastasis to the liver hematogenously. Lymphomatous spreading is rather rare but still happens (4.8%). Exophytic tumor with necrosis should be differentiated from cystic mass of pancreas. The presence of ulcer (43%) and fistula usually indicate origin of gastric tumor but differentiation between smooth muscle tumor and other tumor is necessary. Gastric leiomyoma do not produce annular lesion which happens in small intestine leiomyoma.