Giant Chondroblastic Osteosarcoma Mandible-A Rare Case Report

Abstract

Introduction: Osteosarcoma is a highly malignant neoplasm of bones which most commonly involves the long bones but the involvement of flat bones is very rare. Recurrence rate of flat bones osteosarcomas are high. We are reporting a case of mandibular osteosarcoma treated with radical surgery, adjuvant chemotherapy and radiotherapy to avoid local recurrences. Case Report: A 32 year old male patient presented with complaints of swelling in right side of lower jaw which on examination revealed a smooth, reddish, tender lesion of size 4 × 3 × 3 cm in alveolar ridge opposite to canine and premolar tooth. No neck nodes were palpable. CECT Head & Neck revealed it to be arising from mandible. He underwent segmental mandibulectomy, right selective neck dissection and free fibular reconstruction. On histopathological examination, it was a highly cellular tumor composed of lobules of chondroid material surrounded by spindle-shaped cells with a moderate degree of nuclear atypia with increased mitotic figures. In addition to above findings, therewas a lacy osteoid material in between spindle cells and an evidence of infiltration into the fibro-adipose tissue and skeletal muscle. IHC showed cells to be negative for SMA, panCK, S-100 and positive for Ki67-40%, CD99. A diagnosis of chondroblastic osteosarcoma was made and planned for adjuvant chemotherapy with IAP regimen followed by adjuvant radiotherapy with 60 Gy in 30 fractions using VMAT. He is currently on follow-up for seven months post-surgery and locally disease free. Conclusions: Mandibular osteosarcomas are rare malignancies with high chance of local recurrence and a multimodality treatment with surgery, adjuvant chemotherapy and adjuvant radiotherapy is necessary to reduce local recurrence and to improve survival.