Object: Thyroid carcinoma generally has a favorable prognosis, and patients rarely present with distant metastases. Authors of several studies have proposed piecemeal resection for spinal metastases in thyroid carcinoma; however, few have analyzed the impact of local curative surgery such as total en bloc spondylectomy (TES) for thyroid carcinoma. The purposes of the present study are to determine the strategy of surgical treatment for spinal metastases of thyroid carcinoma and to evaluate the surgical results of and the prognosis associated with TES.
Methods: Twenty-four cases of spinal metastases were retrospectively reviewed. The patients included 16 women and 8 men, with a mean age of 60.7 years. Histological examination showed follicular carcinoma in 15 cases, papillary carcinoma in 8, and medullary carcinoma in 1. Total en bloc spondylectomy was performed in 10 cases; debulking surgery, such as piecemeal excision or eggshell curettage, was performed in 14. The average follow-up time was 55 months (12-180 months).
Results: Four patients had no evidence of disease, 8 were alive with the disease, and 12 had died of the disease. The overall survival rate from the time of surgery was 74% at 5 years. Patients with visceral metastases had a significant, higher risk of death. The survival rate of patients following TES was 90% at 5 years, which was higher than the rate in patients who underwent debulking surgery (63%). However, no significant difference was observed between the 2 types of surgery. There was a local recurrence after debulking surgery in 8 (57%) of 14 cases. Because of the recurrences, reoperation was required after a mean of 41 months. In contrast, there was a local recurrence after TES in only 1 (10%) of 10 cases. The difference between debulking surgery and TES regarding local recurrence was statistically significant.
Conclusions: Total en bloc spondylectomy with enough of a margin provided favorable local control of spinal metastases of thyroid carcinoma during a patient's lifetime.