Four-Year Survival of a Patient With Spinal Metastatic Acinic Cell Carcinoma After a Total En Bloc Spondylectomy and Reconstruction With a Frozen Tumor-Bearing Bone Graft

Acinic cell carcinoma metastasizing to the spine is extremely rare. The authors present a case of acinic cell carcinoma of the parotid gland with subsequent lung and spinal metastases, treated with en bloc spondylectomy. A 41-year-old man presented with a left parotid mass. After being diagnosed with acinic cell carcinoma, he underwent a total parotidectomy. Imaging studies revealed a metastatic osteoblastic lesion in the T4 vertebral body and multiple lung metastases. Total en bloc spondylectomy and reconstruction with a frozen tumor-bearing bone graft were performed to treat the T4 metastasis. Lung metastases were treated with periodic radiofrequency ablation. At the 48-month follow-up, there was no local recurrence of the lesions, and the lung metastases were controlled. The bone graft had fused with the adjacent vertebrae, and the patient had full neurological function and normal daily activities. This report indicates satisfactory long-term outcomes of total en bloc spondylectomy and reconstruction with frozen tumor-bearing bone graft in a patient with acinic cell carcinoma with spinal metastasis. It also emphasizes the benefits of radical resection of spinal metastasis even in cases with multiple organ metastases.