Unusual Presentation of a Rare Chest Wall Tumor: Giant Cell Tumor of Bone

Introduction: Giant cell tumours account 5% of all bone tumours. However, the anterior chest wall is rarely involved . Clinical case: This is a 68-year-old housewife who has been thyroidectomized, for 11 years and is under hormone replacement therapy, and hysterectomized for 6 years after a uterine tumor. She is present for the onset of a 5 month old hard submammary mass on the left associated with left anterior chest pain under mammals. The clinical examination had found an irregular hard mass under left mammary which is fixed to the anterior arch of the 4th left rib. A thoracic x-ray showed a limited left hilo-axillary with an homogenously dense opacity. The thoracic CT scan showed the presence of a thoracic parietal mass of osteolytic tissue density centered on the anterior arch of the 4th left rib; without contrast agent, the surgical exploration through thoracotomy revealed a thoracic parietal tumoral process at the expense of the anterior arch of the 4th limb pushing the corresponding lung inwards. Surgical excision allowed ablation of the whole tumor in monobloc towards a healthy zone. The anatomopathological study of the operative specimen showed a morphological and histopathological aspect compatible with a costal tumor with giant cells. The postoperative recovery was marked by a good clinical and radiological improvement. The last check up after the surgery revealed that the patient was still asymptomatic. Good clinical, biological and radiological improvement was noted with a decline of 8 months. Conclusion: Giant cell tumors are aggressive bone tumors, yet histologically benign. The chosen examination is a thoracic CT scan with surgical treatment. A clinical and radiological monitoring is necessary. The recurrence is rare, but it usually necessitates a second surgery. The objective of this clinical observation is to highlight the possibility, although rare, of a giant cell tumor in case of the swelling of the soft parts, and a lytic lesion of the anterior part of a rib. Therefore, this tumor must be added to the list of diagnoses to be mentioned in this situation.