BACKGROUND Desmoid tumors, also known as aggressive fibromatosis, are extremely rare, accounting for less than 3% of soft-tissue sarcomas and less than 0,03% of all neoplasms. The diagnosis is usually delayed because of the lack of specific symptoms, and can sometimes lead to serious and, even fatal complications. CASE PRESENTATION We report the case of a 27-year-old male patient presenting with the clinical picture of acute appendicitis. During the operation, we found a tumor in the jejunum with a necrotic zone and perforation on its surface, causing hemorrhagic effusion into the abdominal cavity and subsequent peritonitis. The tumor was removed with negative margins via resection of the small bowel. The final histological result showed aggressive fibromatosis. CONCLUSIONS Aggressive fibromatosis remains a serious problem with the possibility of locally aggressive behavior with high rates of recurrence. Sometimes, its clinical and macroscopic recognition can be immensely tricky. As shown by our patient, on rare occasions, desmoid tumors can lead to acute surgical abdomen requiring an emergency operation.

中文翻译：

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破裂的类胶质瘤模仿急性阑尾炎-急诊手术的罕见原因。

背景技术类腺瘤，也称为侵袭性纤维瘤病，极为罕见，仅占软组织肉瘤的3％和所有肿瘤的0.03％。由于缺乏特定症状，通常会延迟诊断，有时会导致严重甚至致命的并发症。病例介绍我们报告了一名27岁的男性患者，其临床表现为急性阑尾炎。手术期间，我们在空肠中发现了一个具有坏死区并在其表面穿孔的肿瘤，导致出血性积液渗入腹腔并随后发生了腹膜炎。通过切除小肠切除肿瘤，切缘阴性。最终的组织学结果显示侵袭性纤维瘤病。结论侵袭性纤维瘤病仍然是一个严重的问题，可能会导致局部侵袭性行为复发率高。有时，其临床和宏观识别可能非常棘手。如我们的患者所示，在极少数情况下，类胶质瘤可导致需要紧急手术的急性手术腹部。