Dedifferentiated Chondrosarcoma of Proximal Tibia and Fibula with an Infected Ulcer: A Case Report

INTRODUCTION Dedifferentiated chondrosarcoma (DDCS) is a rare and malignant form of primary bone tumor refractive to chemotherapy and radiotherapy. It accounts for 1-2% of all primary bone tumors. Surgical resection, limb-salvage surgeries and amputation remain the mainstay of treatment. The prognosis of dedifferentiated chondrosarcoma is poor. CASE REPORT We report a case of a 51-year-old male having a swelling and an ulcer distal to the left knee later diagnosed with dedifferentiated chondrosarcoma of proximal tibial and fibular metaphysis. Although DDCS is a highly malignant tumor, no metastasis was found and the patient was treated with transfemoral amputation. Post-operative histopathology showed nuclear atypia, binucleated and multinucleated chondrocytes with spindling and neoplastic cells arranged in storiform pattern and giant cells which confirmed the diagnosis of DDCS. CONCLUSION Early diagnoses and treatment are important while treating these tumors in order to prevent morbidity and mortality.