Favorable outcomes with, without treatment for patients with papillary thyroid cancer

Individuals with papillary thyroid cancers of any size that are limited to the thyroid gland and without extraglandular extension or lymph node metastases at presentation appear to have favorable outcomes, regardless of whether they received treatment within the first year of diagnosis, according to a new study.

Using data on cancer cases and individual treatment from the National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) program and National Vital Statistics System, researchers identified 35,663 patients with papillary thyroid cancer that had not spread to the lymph nodes or other areas and was limited to the thyroid gland. Of this eligible group, 1.2% did not undergo immediate, definitive treatment.

The researchers determined that the 20-year survival rate of the treated group was 99% compared with 97% for the untreated group.

In the untreated cohort, six patients died from their cancer during six years of follow-up. This number was not significantly different from the rate of cancer death among treated patients (n=161) during an average 7.6 years of follow-up (P=.09).

“These data help put management decisions about localized papillary thyroid cancer in perspective: papillary cancers of any size that are confined to the thyroid gland, have no lymph node metastases at presentation and do not show extraglandular extension are unlikely to result in death due to cancer,” the researchers wrote.

One option for clinicians is to observe cancers that fall into this category for one year or longer, according to the researchers.

“When treatment is elected, the cancers in this category can be managed with hemithyroidectomy or total thyroidectomy and the prognosis will be the same,” they wrote.

Call for individualization

In an accompanying editorial, Erich M. Sturgis, MD, MPH, and Steven I. Sherman, MD, of the University of Texas M.D. Anderson Cancer Center, argued for keeping the individual patient’s best interest at the center of decision making.

“If the 5-, 10- and 20-year thyroid cancer-specific survival estimates are accurate and the entire 35,000 patients with papillary thyroid cancer confined to the thyroid gland were observed, crudely, between 500 and 700 excess patients would have died of papillary thyroid cancer. Certainly, most of these hypothetical 500 to 700 people would have wished their physicians had offered them the treatment that had ‘statistically’ better survival (ie, surgery),” the editorialists wrote.

Further, “we would wonder if the six people who died of their thyroid cancer in this real yet very selected and/or small ‘no treatment’ group would have agreed that a statically significant 2% difference in survival was not clinically relevant,” they wrote. – by Matthew Brannon

Davies L. Arch Otolaryngol Head Neck Surg. 2010;136:440-444.

Sturgis EM. Arch Otolaryngol Head Neck Surg. 2010;136:444-446.