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Spontaneous Regression of Multiple Pulmonary Metastasis of Sacral Chordoma

Case: A 53-year-old man was referred to our institution for the treatment of sacral chordoma and underwent a wide resection. Multiple lung metastases were observed in both the lungs, a year after the surgery, and the diagnosis was confirmed by biopsy. The patient refused treatment, and the lesions continued to increase in size gradually. However, 3 years and 6 months after the surgery, computed tomography of both the lungs showed spontaneous regression of the lesions without any obvious causes. The metastatic lung lesions had disappeared at the final follow-up, 7 years and 5 months after the multiple pulmonary metastases were diagnosed. Conclusion: We report the first case of spontaneous regression of pathologically proven pulmonary metastases of a sacral chordoma.