Current Thoracic Surgery

Fibro-osseous lesions of the rib are rare benign entities that frequently mimic primary or secondary chest wall malignancies. They are most commonly reported in the sixth to eighth ribs, with lower rib involvement being exceptionally uncommon. Radiological findings are often nonspecific, thus, histopathological evaluation is crucial for establishing a definitive diagnosis. We report the case of a 32-year-old female presenting with left lower chest pain and a firm, gradually expanding swelling over the left posterolateral chest wall. Imaging revealed a lytic lesion of the left 11th rib, raising suspicion of a primary bone tumor. Given the diagnostic uncertainty, resection of the affected rib segment was performed. The postoperative course was uneventful, and the patient was discharged on the fourth postoperative day. Histopathology confirmed a benign fibro-osseous lesion. Fibro-osseous lesions of the rib are rare and diagnostically challenging due to their radiological resemblance to malignant tumors. Involvement of the 11th rib is infrequent, and to our knowledge, has not been previously documented. This case showed the importance of surgical excision in achieving diagnostic certainty in the case of a fibro-osseous lesion.