Large Conventional Osteosarcoma of the Proximal Humerus in a 13-Year-Old Child: Case Report

Introduction: Osteosarcoma is the most common primary malignant bone tumor in children. It is highly aggressive and has a poor prognosis. A late presentation modifies and makes difficult the management affecting the survival of children. We report the case of a large conventional osteosarcoma in a 13-year-old girl. Case Presentation: Adolescent girl admitted for painful swelling of the left shoulder with absolute functional impotence of the thoracic limb and severe anemia. The painful swelling was thought to have been caused by a minor trauma that had occurred six months previously. The patient’s general condition was poor, and she presented with a large, shiny, painful mass over the shoulder and upper 2/3 of the left arm, measuring 28 cm long by 28 cm wide and 57 cm in circumference, and a large fistulous axillary adenopathy. CT scan showed a tumour lesion of the left humerus with liver and lung metastases, raising suspicion of osteogenic osteosarcoma. The tumor was classified according to TNM staging: T2N1M1(a + b). Management was modified when uncontrolled bleeding developed. It consisted of an extended amputation of the left thoracic limb. Pathological analysis showed a high-grade conventional osteosarcoma. Quality improvement was obtained for thirty days, followed by the onset of dyspnea. The evolution was towards death at forty days post-operatively. Conclusion: Osteosarcoma is a highly aggressive cancer. Delayed treatment leads to a fatal outcome. Early diagnosis is one of the challenges to be met in order to improve survival.