Low-grade myofibroblastic sarcoma with abdominal pain, a stuffy nose, hearing loss, and multiple cavity effusion: a case report and literature review

Low-grade myofibroblastic sarcoma (LGMS) is a rare, low-grade, malignant tumor and is mainly composed of myofibroblasts with varying degrees of differentiation. LGMS results in considerable diagnostic difficulty. We report a case of LGMS that occurred in multiple organs, including the diaphragmatic pleura, and head and neck region. A 34-year-old man was hospitalized in 2014 after coughing and shortness of breath for 10 days, and abdominal distension, abdominal pain, and bilateral lower extremity edema for 4 days. Before this admission, he had an abdominal tumor diagnosed in 1994 and 2003, a nasopharynx tumor in 2010, and a temporal lobe tumor in 2013. All tumors were resected surgically and the diagnosis was atypical fibrous histiocytoma and atypical fibrous xanthoma. Before surgeries for these tumors, no positron emission tomography-computed tomography (PET-CT) or whole-body scans were performed, and after surgery, there was no follow-up. After thoracoscopy and PET-CT after the most recent admission, the patient was diagnosed with LGMS with metastasis to the bone, nodes, and thoracic and abdominal cavities. The patient was discharged with albumin infusion treatment. Although LGMS is rare, it is potentially serious. Therefore, clinicians should be aware of such disease and make an early diagnosis and perform close follow-up.