Presence of thyroglobulin after radioiodine treatment may indicate recurrence of thyroid cancer

Detecting thyroglobulin (Tg) after initial surgery and radioactive iodine (131I) therapy for thyroid cancer may be predictive of an early cancer recurrence, according to a study reported at the 14th International Thyroid Congress, Doctor's Guide reports.

"Our study seems to indicate that, following initial therapy, a negative high-dose postoperative WBS [whole body scan] with detectable Tg is a valuable predictor for earlier and more recurrences, but is not associated with survival," said Deborah van Dijk, lead author. "We set out to assess the prognostic value of detectable thyroglobulin by comparing patients with a negative post-therapeutic WBS with either detectable or undetectable Tg."

Researchers from the University Medical Center of Groningen in the Netherlands found that out of 399 patients, 72 had positive Tg levels and negative post-therapeutic WBS. Meanwhile, a total of 399 individuals had negative Tg levels and the same WBS following the last dose of 131I treatment. The remaining 68 patients showed residual macroscopic disease.

The rate of recurrence and overall mortality within the positive Tg and negative Tg groups were compared with that in the general population. The outcome demonstrated that in the positive Tg group, recurrences were seen much earlier and more frequently than in the negative group.

According to the National Cancer Institute, there are 19,500 thyroid cancer diagnoses in the U.S. annually.