DOI: https://doi.org/10.36347/sjmcr.2026.v14i10.042

Pages: 2302-2306

Giant cell tumor of bone (GCTB) is a rare, locally aggressive bone neoplasm with exceptional metastatic potential. Distant metastases occur almost exclusively in the lungs and are reported in approximately 1-9% of cases, with rates closer to 2-3% in large contemporary series. We report the case of a 37-year-old woman with a dedifferentiated GCTB of the proximal left tibia with a sarcomatous component, treated with chemotherapy followed by surgery. Two years after the initial diagnosis, she presented with a cough, an hemoptysis, left-sided chest pain, and dyspnea. Chest computed tomography revealed a large left pulmonary mass associated with bilateral pulmonary nodules, a pleural effusion, and osteolytic lesions of vertebrae L1, L3, L4, L5, and S1. Transthoracic biopsy of the pulmonary mass confirmed metastatic GCTB on the immunohistochemical analysis. The case was discussed at a multidisciplinary team meeting, where treatment with denosumab and pleural talc pleurodesis was indicated. However, the clinical course deteriorated rapidly, and the patient died before these treatments could be initiated. This case is noteworthy not only because pulmonary metastases from GCTB are rare, but also because they were diffuse, symptomatic, and rapidly progressive in the setting of a dedifferentiated primary tumor with a sarcomatous component. It highlights the need a long-term follow-up, particularly in biologically aggressive forms.