From Science Daily with additional comments from Robert B. Barriger, MD, radiation oncologist with OHC
August 14, 2018
Anaplastic thyroid cancer is one of the least common but most aggressive forms of thyroid cancer. Add to that, it’s resistance to cancer treatments. Patients diagnosed with the disease have an average lifespan of about five months after diagnosis. The standard treatment for the condition includes seven weeks of radiation, often with chemotherapy.
Now a paper published in the journal Thyroid suggests an alternative. Rather than conventional radiation therapy, the study led by Sana Karam, MD, PhD, investigator at the University of Colorado (CU) Cancer Center and assistant professor in the CU School of Medicine Department of Radiation Oncology, suggests that thyroid tumors may be more susceptible to treatment with precisely targeted radiation known as stereotactic body radiation therapy (SBRT), and possibly with fewer side effects.
“We use SBRT here locally at OHC and it allows us to deliver a larger dose of radiation in fewer treatments. And the patient’s quality of life is better because there are few side effects, the most common being slight fatigue for about a week after treatment,” said Robert B. Barriger, MD, radiation oncologist with OHC. “Dr. Karam’s study is important because SRBT isn’t typically used for thyroid cancer and, based on the research, it may eventually be better than conventional radiation for patients with anaplastic thyroid tumors.”
“My biggest thing was seeing if we could replace seven weeks of radiation with a shorter regimen, say three sessions of targeted radiation instead of thirty of conventional radiation,” Dr. Karam said.
Dr. Karam and team were able to show that anaplastic thyroid cancer cells are almost universally resistant to conventional radiation therapy. She wondered if targeted radiation might succeed where conventional radiation failed. In collaboration with other CU researchers, Dr. Karam tested these two types of radiation in mice.
“What we found is that not only is this condensed regimen of targeted radiation equivalent to conventional radiation therapy, but it’s actually superior, not only in terms of local control but also distantly,” she said. “It may be that SBRT eradicates the root of the cancer so that it can’t continue to send out cells that lead to spreading to other parts of the body. Or it may be that SBRT wakes up the immune system to the presence of cancer, which helps the immune system combat cancer elsewhere in the body,” Karam said.
Whatever the mechanism, mice treated with SBRT had less cancer and lived longer than mice treated with conventional radiation.
Source: University of Colorado Anschutz Medical Campus. (2018, May 21). Ice cream funds research showing new strategy against thyroid cancer. ScienceDaily. sciencedaily.com/releases/2018/05/180521131536.htm.
