Study design: Case report.
Objective: To demonstrate that interferon alfa-2b is a therapeutic option for obtaining long-term control of recurrent and metastatic giant cell tumor of spine.
Summary of background data: Interferon alfa served as angiogenesis inhibitor and has been successfully used to treat giant cell tumor of long bones and facial bones. Up to date, no report is found with regard to the use of interferon as a stand-alone treatment for unresectable, recurrent, and metastatic giant cell tumor originated from the spine.
Methods: A 29-year-old woman with C1 and C2 giant cell tumor was treated by radiotherapy, intralesional curet, and chemotherapy orderly. Tumor recurred after 2 years. A second curet was undertaken. Tumor recurred second time and caused severe spinal cord compression. Lung metastasis was diagnosed simultaneously. A 24-year-old man with recurrent giant cell tumor of T5 and T6 was treated by spondylectomy of T5 and T6. Six months later, a giant metastatic lesion was found in sacrococcygeal region, which was excised and proved to be giant cell tumor of bone. Four months later, 2 recurrent lesions were found beside the rectum. Interferon alfa-2b at a dose of 3,000,000 U/m was then administered subcutaneously everyday for both patients for 3.5 and 3 years, respectively.
Results: No major complications related to the use of interferon occurred. The lesion in C1-C2 of the first patient regressed steadily and was restricted and encircled within the lateral mass. The metastatic lesions in the lungs also significantly reduced. The pararectal lesions of the second patient disappeared completely.
Conclusion: Interferon therapy may be an effective and safe treatment for spine giant cell tumor recurrence and metastasis in soft tissue. The effectiveness may be time and dosage dependent.