MONDAY, Feb. 24, 2014 (HealthDay News) -- Thyroid cancer that develops after treatment for another type of cancer is more deadly than primary thyroid cancer, according to a new study.
The findings highlight the importance of screening young cancer survivors to detect early signs of secondary thyroid cancer, the researchers said.
They examined data from amore than 41,000 cases of thyroid cancer in teens and young adults in the United States from 1998 to 2010. Of those patients, about 3 percent had previously been treated for another type of cancer.
Secondary thyroid cancers were more likely to be small but to occur in more than one location, compared to primary thyroid cancers, the study found. Survival rates for patients with both types of thyroid cancer were considered "excellent" at more than 95 percent, but those with secondary cancer were 6.6 times more likely to die than those with primary cancer.
The results suggest that there may be differences between the two types of thyroid cancers, according to the authors of the study published online Feb. 24 in the journal Cancer.
"This study will hopefully spur future research that will investigate if there are any causes -- biologic, environmental, prior treatment-related, or access to care disparities -- to account for the survival differences in these secondary cancers," study author Dr. Melanie Goldfarb, at the University of Southern California's Keck School of Medicine, said in a journal news release.
Thyroid cancer is among the five most common cancers in teens and young adults aged 15 to 39.
The American Cancer Society has more about thyroid cancer.