摘要
典型有症狀的胃腸道基質腫瘤(gastrointestinal stromal tumor, GIST)在CT檢查的特徵為腫瘤體積通常比較大，外生性，因血管豐富，注射顯影劑後通常會有明顯的顯影，腫瘤中間可能因血流供應不足而有壞死。當腫瘤幾乎完全壞死，剩下仍存活的腫瘤組織不多的時候，容易被忽略，誤以為不是一個腫瘤。故此，出現一個很難解釋的腹部膿瘍，也要考慮小腸基質瘤完全壞死這個可能性。基質瘤急性破裂會以出血的形式表現，慢性則侵犯附近的組織器官，形成瘻管。這個病例，小腸基質瘤有侵犯到附近器官的大腸，引起缺血性穿孔而導致氣腹，則是不尋常的表現。故此，腹部出現大量的游離氣體的時候，需要考慮急性的腸胃道穿孔，而非膿瘍斑點狀氣體的破裂。
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