Granular Cell Tumor of the Right Thigh: A Case Report and Literature Review

Jue HouGongji YaoYifeng Zheng^*

• Huzhou University, Huzhou, China

Background: Granular cell tumor (GCT) is a rare soft tissue tumor, and granular cell tumors originating from the extremities (GCT-E) are even rarer. In this study, by reporting one case of GCT-E in the right thigh and conducting a literature review, we analyzed the clinical and imaging characteristics of this disease to improve the level of early diagnosis of GCT-E. Case Presentation:A 49-year-old male patient was admitted to our hospital due to a "mass in the medial aspect of the right thigh for more than 1 year, with progressive enlargement in the past week." Initial computed tomography and magnetic resonance imaging (MRI) examinations revealed a soft tissue mass in the inferior segment of the right medial femoral muscle. Positron em ission tomography-computed tomography (PET-CT) examination showed increased fluorodeoxygl ucose metabolism, suggesting the possibility of a benign or low-grade malignant tumor. He underwent a pathological biopsy at the Second Affiliated Hospital of Zhejiang University, and the biopsy result indicated an atypical GCT.Subsequently, the patient underwent complete resection o f the medial femoral muscle, and the postoperative pathological and immunohistochemical results were consistent with the biopsy diagnosis. Discussion: GCT originating from the extremities is extremely rare, with a very high preoperative misdiagnosis rate.We summarized the common MRI imaging findings of GCT, based on a review of the literature, and found that the possibility of misdiagnosis of schwannomas is the highest. To address this diagnostic challenge, we proposed imaging signs that can be used for differential diag nosis. PET-CT has potential value in the auxiliary imaging diagnosis of patients with GCT, while t he final diagnosis still depends on pathological immunohistochemistry.Extensive surgical resectio n is the main treatment for GCT-E. Currently, the efficacy of radiotherapy and chemotherapy rema ins controversial, and regular postoperative follow-up is required to monitor recurrence.In the pres ent case, the patient remained recurrence-free during 12 months of follow-up.