Ossifying fibromyxoid tumor in the lower extremity mimicking a sebaceous cyst. Case report and literature review

Introduction: Ossifying fibromyxoid tumor (OFMT) is an uncommon soft tissue neoplasm, with malignant potential and unclear histogenesis. OFMT exhibits a spectrum of histopathologic features including benign (typical), atypical and malignant subtypes. To the best of our knowledge, about 300 cases have been reported worldwide. We present the first reported case from Qatar. Presentation of case: A 36-year old Egyptian male, with no comorbidities was admitted electively as a day case for excision of left thigh suspected sebaceous cyst under local anesthesia. History, physical examination and soft tissue ultrasound imaging were unremarkable. Intraoperatively, the patient was found to have a hard-calcified mass adhering to the surrounding fascia which was excised en bloc. The histopathology result was of ossifying fibromyxoid tumor. The post-operative course along with 40 months follow-up were uneventful in terms of surgical complications and recurrence. Discussion: OFMT has marked features in terms of cytology. Though it is difficult to diagnose preoperatively, it should be considered in tumors involving soft tissue that demonstrate prominent ossification and calcification. Conclusion: OFMT is a rare soft tissue neoplasm, and should be considered as a differential diagnosis in any subcutaneous swelling with a bony component. All OFMT patients should undergo a long course of follow-up to rule out and assess any recurrence or metastasis in the malignant variants.