Neoadjuvant chemotherapy in 29 patients with locally advanced follicular or Hürthle cell thyroid carcinoma: a phase 2 study.

Background: It is believed that chemotherapy (ChT) is ineffective in follicular thyroid carcinoma (FTC) and Hürthle cell thyroid carcinoma (HCTC). The aim of our retrospective study was to find out whether neodjuvant ChT before thyroid surgery had any effect on the size of primary tumor in patients with FTC or HCTC.
Methods: The study included 29 patients (20 women, 9 men; mean age: 60.8 years) with FTC or HCTC who had T3 or T4 tumor and were treated with neoadjuvant ChT from 1979 to 2004. A mean tumor diameter was 9.3 cm. Extrathyroid growth of tumor was present in 15 patients. Regional and distant metastases were detected in 6 and 12 patients, respectively. With respect to the site of metastatic spread, the lung was involved in eight patients and the skeleton in five. ChT consisted of vinblastine in 19 cases, vinblastine with adriamycin in 5 cases, or other ChT regimens in 5 cases.
Results: Altogether, 67 cycles of ChT were given and tumor size decreased by >50% in 13 patients (=45%). ChT was effective in patients with FTC and HCTC in 47% and 43%, respectively. In the patients with and without distant metastases, the primary tumor size decreased by >50% in 17% and 65% (p=0.02), respectively. R0, R1, and R2 resection was performed in 15, 10, and 4 cases, respectively. Histopathology revealed that ChT (i.e., wide areas of tumor necrosis) was effective in seven patients (24%). The 5- and 10-year cause-specific survivals of the patients were 77% and 47%, while the 5- and 10-year disease-free intervals were 57% and 46%, respectively. Six patients are alive (median survival: 162 months), four of them have no evidence of disease, six patients died of other causes (median survival: 101 months), while 17 patients died of FTC or HCTC (median survival: 72 months). Among them, 16 died of distant metastases, while only one succumbed to locoregional recurrence and distant metastases.
Conclusions: ChT before surgical procedure may be effective in order to decrease the tumor size in FTC or HCTC in 45% of patients.