New Paradigms Emerging in Diagnosis, Management of Thyroid Cancer

In order to manage those numbers, Dr. Tuttle emphasized the importance of detection of recurrent disease and persistent disease and the importance of risk stratification.

Risk stratification is much more than the argument about total thyroidectomy versus less than total, or yes or no on radioactive iodine, Dr. Tuttle said. Risk stratification is much more than that; it helps me understand which test to use.

Dr. Tuttle said the good old days are gone when people either had thyroid cancer or they didn’t.

Life was easy back then; their scan was either positive or negative, he said. And then we messed things up by developing thyroglobulin assays. We had all those people that we thought were cured of thyroid cancer and now, all of a sudden, we’re not so sure. If you look at the literature of the 1970s and 80s, this was a big puzzle. How could people have negative scans, but yet we’re measuring all this thyroglobulin?

The answer, he said, is that now researchers understand that thyroglobulin is a marker of persistent disease.

The ultrasound helped us out a lot because most of these patients had little low-level thyroglobulin after their total thyroidectomy and after radioactive iodine, Dr. Tuttle said. In the last 10 years, though, there has been a dramatic fall-away from radioactive iodine. When I was a fellow in the army, I was taught that I should talk people into doing radioactive iodine scans once a year for five years, with traditional hypothyroid withdrawal, taking their pills away. And, if you can talk somebody into going off their pills once a year for five years, we would like to hire you at Memorial to write grants for us, because you are a very persuasive surgeon.

Fortunately, he continued, over the past several years, there has been a big shift away from that approach.

In the setting of someone who’s had a total thyroidectomy and radioactive iodine, Dr. Tuttle said thyroglobulin should be measured every 6 to 12 months for the first year or two and then once a year after that. Ultrasound should be performed six months after surgery and again a year after surgery.

It’s not good enough to risk-stratify someone five minutes after surgery, he said. We are going to continually risk-stratify them based on time and all of the information that we have.

Another advantage of thyroglobulin measurement, Dr. Tuttle pointed out, is that it allows the physician to localize the disease.