Thyroid Tumor Case could Uncover Clues on Fighting Cancer
One thyroid tumor case could uncover clues on how researchers can use drugs to more effectively treat cancer. Researchers reported that 56-year-old Grace Silva's thyroid cancer completely disappeared for 18 months after being treated with everolimus (Afinitor). However, her tumor developed resistance to the drug and started to spread.
"The study of patients with extraordinary responses can yield critically important insights," study first author Dr. Nikhil Wagle, an oncologist at Dana-Farber Cancer Institute, said in the news release reported by Philly. "These studies could help us develop methods for matching patients to drugs, highlight effective uses for otherwise 'failed' therapies and design new therapeutic strategies to fight cancer."
In this case, the researchers had identified two new gene mutations in Silva's tumor. One of the mutations made the tumor sensitive to everolimus, which would explain why the drug was so effective. The other mutation, however, appeared to be linked to the development of drug resistance. That mutation negated the sensitivity of the tumor to the drug. The tumor went on to infect her lungs. Surgery, radiation and chemotherapy have not worked so far.
The researchers concluded that if they screened a patient's cancer DNA before and after treatment, they could potentially find clues on how the cancer develops resistance to a certain drug. By tracking the cancer, the team hopes to find a way to guide the treatment and prevent it from becoming ineffective.
"This is personalized, precision medicine at its best," study senior author Dr. Jochen Lorch, a thyroid cancer specialist at the Head and Neck Treatment Center at Dana-Farber, in Boston, said.
The researchers are currently testing a new kind of drug in clinical trials. The patient, who has been alive for four years since her diagnosis, will get the treatment.
The study was published in the New England Journal of Medicine.