Primary Chondrosarcoma of the Right Fourth Rib Resected at the Marginal Margin: A Case Report.

Primary chondrosarcoma of the ribs is relatively rare, and its basic treatment is surgical resection. In cases with positive resection margins, additional resection is considered, but its indications are unclear. However, reported cases with positive resection margins have been limited. We report a 71-year-old man whose medical checkup revealed an abnormal shadow in the chest. The findings from chest computed tomography, axial T2-weighted magnetic resonance imaging (MRI), and contrast-enhanced MRI led to a diagnosis of chondrosarcoma of the right fourth rib, and surgical resection was performed. The chest wall defect was reconstructed with a Marlex mesh. Postoperative histopathologic diagnosis was grade 2 chondrosarcoma. Gross resection margins, which were marginal, were negative, and the resection margin was grade 1. The patient was followed up without adjuvant therapy and did not undergo additional surgery. For chondrosarcomas with negative gross margins but a marginal margin, additional resection should be considered depending on the histologic grade of the margins. In cases with extensive resection of the chest wall, it is useful to reconstruct the chest wall while paying careful attention to infection control.