New findings on thyroid nodule cancer risk will be incorporated into the American Thyroid Association’s new guidelines for nodule screening.

New research published today in the Journal of the American Medical Association has concluded that even thyroid nodules that grow in size are unlikely to become cancerous.

The research team followed 992 patients in Italy with benign thyroid nodules for five years, beginning in 2006.

“The results of our study suggest that most benign nodules exhibit no significant size changes over time, and some actually decrease in size,” said Sebastiano Filetti, professor of internal medicine at the University of Rome Sapienza, Italy, principal investigator of the study, and American Thyroid Association (ATA) member, in an interview with Healthline. “Only a subgroup of nodules can be expected to grow, about 15 percent in our series.”

The research also suggests that growing nodules do not, in fact, require more frequent screenings.

“Nodule growth is regarded as a possible predictor of malignancy,” said Filetti. “This was not confirmed in our study. If a nodule is benign it is very likely that it will remain benign during follow-up, even if it grows.”

While screening nodules is crucial for early cancer detection, the ATA reports that more than 90 percent of nodules remain noncancerous. Nodule growth was thought to predict which nodules would develop cancer.

Learn More: Do a “Neck Check” to Detect Thyroid Cancer »