Al Abdulsalam Ali, Al Safi Sarah, Aldaoud Sami, Al-Shadidi Nimer, Dhar Piyaray Mohan
Department of General Surgery, Al-Adan Hospital, Hadiya 46969, Kuwait.
Histopathology Department, Al-Adan Hospital, Hadiya 46969, Kuwait.
Int J Surg Case Rep. 2022 Nov;100:107710. doi: 10.1016/j.ijscr.2022.107710. Epub 2022 Sep 30.
Intramuscular myxoma (IM) is a rare benign soft tissue tumor that involves the musculoskeletal system with a reported incidence of 0.1-0.13 per 100,000. The mean age of diagnosis is 40-70 years of age, with female predilection. The most common site of involvement is the thigh, however, it may present in other areas such as the upper arm, calf, and buttock.
A case of a 45-year-old female without a significant past medical or surgical history who presented with 3-year history of a slow-growing, painless mass in her left upper thigh. MRI scan was performed which showed intramuscular soft tissue mass lesion 9 × 6 × 4.5 cm implicating the left distal vastus medialis muscle. A fine needle aspiration was inconclusive so a core needle biopsy was performed which was suggestive of intramuscular myxoma. A complete surgical excision of the mass was done and the postoperative period was uneventful and patient was discharged home. The final histopathological examination confirmed the diagnosis of intramuscular myxoma.
Intramuscular myxoma is a rare benign soft tissue neoplasm. 50 % of cases commonly occur in the thigh. IM has an unknown etiology, however, the literature has showed common gene mutations such as the GNAS gene mutations (Guanine nucleotide binding protein, alpha stimulating). Imaging modalities such as ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) are useful in diagnosis of soft tissue mass but not specific to intramuscular myxoma. Histopathological examination is the gold standard for diagnosis. The treatment of choice is surgical excision with clear margins to prevent recurrence, which is extremely rare.
Intramuscular myxomas, although benign and rare, should be in the differential diagnosis of soft tissue lesions due to the similarity they share with malignant tumors such as sarcomas. Histopathological examination is the gold standard for diagnosing a soft tissue lesion and surgical excision is the treatment of choice.
肌内黏液瘤（IM）是一种罕见的良性软组织肿瘤，累及肌肉骨骼系统，报告发病率为每10万人中有0.1 - 0.13例。诊断的平均年龄为40 - 70岁，女性更易患病。最常见的受累部位是大腿，不过也可能出现在其他部位，如上臂、小腿和臀部。
一名45岁女性，既往无重大内科或外科病史，因左大腿上部缓慢生长、无痛性肿块3年就诊。进行了MRI扫描，显示肌内软组织肿块病变大小为9×6×4.5厘米，累及左股内侧肌远端。细针穿刺结果不明确，因此进行了粗针活检，提示为肌内黏液瘤。对肿块进行了完整的手术切除，术后恢复顺利，患者出院。最终组织病理学检查确诊为肌内黏液瘤。
肌内黏液瘤是一种罕见的良性软组织肿瘤。50%的病例常见于大腿。IM的病因不明，然而，文献显示常见基因突变，如GNAS基因突变（鸟嘌呤核苷酸结合蛋白，α刺激型）。超声、计算机断层扫描（CT）和磁共振成像（MRI）等影像学检查对软组织肿块的诊断有用，但对肌内黏液瘤不具有特异性。组织病理学检查是诊断的金标准。治疗选择是手术切除，切缘要清晰以防止复发，复发极为罕见。
肌内黏液瘤虽然是良性且罕见的，但由于它们与肉瘤等恶性肿瘤有相似之处，应列入软组织病变的鉴别诊断中。组织病理学检查是诊断软组织病变的金标准，手术切除是治疗的选择。
