According to results from a Phase II clinical trial, use of targeted radiation therapy with [90Yttrium-DOTA]-TOC may improve outcomes among patients with iodine-refractory, metastatic thyroid cancer. These results were published in Cancer.
The thyroid gland is located in the front of the neck and is attached to the lower part of the voice box (larynx) and to the upper part of the windpipe (trachea). It has two sides, or lobes, that are connected by a narrow neck. The thyroid gland produces thyroid hormones, which regulate metabolism, growth, and development and are essential for life.
Thyroid cancer is often treated by surgery and radioactive iodine. Management of cancer that is resistant to conventional treatment can be challenging, and researchers continue to explore new approaches to treatment. Several new targeted agents appear to be effective for patients with iodine-refractory thyroid cancer, including Nexavar® (sorafenib), axitinib, and motesanib diphosphate.
[90Yttrium-DOTA]-TOC provides targeted radiation therapy. It is administered intravenously, binds to a specific protein on the surface of the tumor cell, and emits radiation. To evaluate the use of [90Yttrium-DOTA]-TOC in the treatment of iodine-refractory, metastatic thyroid cancer, researchers in Europe conducted a Phase II clinical trial among 24 patients.
- Seven patients (29%) responded to treatment with [90Yttrium-DOTA]-TOC. Treatment response was assessed by measuring serum thyroglobulin levels.
- Median survival was 17 months from the start of treatment. Patients who responded to treatment experienced better survival than patients who did not respond to treatment.
These results suggest that [90Yttrium-DOTA]-TOC is active against iodine-refractory, metastatic thyroid cancer, and may improve survival for some patients. The authors recommend that future studies assess the effect of increasing the number of treatment cycles.
Reference: Iten F, Muller B, Schindler C et al. [90Yttrium-DOTA]-TOC response is associated with survival benefit in iodine-refractory thyroid cancer. Cancer. 2009;115:2052-62.