15th International Thyroid Congress, 85th Annual Meeting of the American Thyroid Association:
American Thyroid Association Pediatric Guideline Discussed at ITC/ATA
Presented at the meeting by Steven G. Waguespack, MD
Steven G. Waguespack, MD summarized several key aspects of the Management Guidelines for Children with Thyroid Nodules and Differentiated Thyroid Cancer, which were sponsored by the American Thyroid Association and co-sponsored by the Pediatric Endocrine Society. These guidelines were ultimately endorsed by other societies after they were accepted for publication. Dr. Waguespack is Professor, Department of Endocrine Neoplasia and Hormonal Disorders, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX.
The need for a pediatric guideline was obvious realizing there was only one recommendation in the adult guideline for children—specifically, thyroid nodules in children should be worked up basically the same way as in adults. Dr. Waguespack pointed out that clinically relevant questions specific to the pediatric population were developed, a comprehensive literature review was conducted, followed by meetings, discussions, commentaries, and peer review.
Fourteen task force members from seven countries were involved in the development of the pediatric guideline. Areas of specialty included adult and pediatric endocrinology, endocrine surgery, molecular genetics, molecular biology, nuclear medicine, and radiology. The total number of recommendations is 34 with 38 sub-recommendations, and 405 references.
Why the need for separate pediatric guidelines? Dr. Waguespack responded, “Thyroid nodules are quite uncommon, and when they present in children, there's a higher risk of malignancy. PTC [papillary thyroid cancer] is overwhelmingly the most common subtype of thyroid cancer we will see, and rarely we will see poorly differentiated carcinomas and frankly, anaplastic carcinomas.”
Children with papillary thyroid cancer typically have:
- Larger tumors
- More lymph node metastases
- More pulmonary metastases
- Higher rates of recurrence
Usually, children with PTC have an excellent outcome and prognosis. The 30-year mortality is only 2% in the pediatric population.
“The cancers are more differentiated; they're more responsive to radioactive iodine, and this is probably related to underlying differences in molecular oncogenic events. But children are uniquely at risk for long-term complications. We've seen that children have more lymph node metastases, and—at least in the United States—they tend to have a hard time getting access to high-volume thyroid cancer surgeons,” stated Dr. Waguespack. Furthermore, surgical intervention may be preferred to minimize the effects of ionizing radiation on normal thyroid tissue.
Indeterminant Thyroid Nodules
“The risk of cancer in a child with an indeterminant biopsy is actually much higher than that of an adult. And in addition, there are no studies validating the use of molecular testing in this situation in pediatrics. So we felt that an indeterminant nodule should go to surgery implying a hemithyroidectomy in this case,” stated Dr. Waguespack.
- Dr. Waguespack strongly emphasized, “I think the most important thing a child with thyroid cancer can do is to meet the right surgeon at the beginning. And then, subsequently, hopefully endocrinology and nuclear medicine can judiciously use radioactive iodine to help treat any remaining disease.”
A post-treatment scan is particularly vital in children. The guideline recommends the judicious use of SPECT/CT to help clarify the location of iodine avid disease. After primary treatment is completed, thyroid stimulating hormone (TSH) is recommended. During the monitoring mode, ultrasound is recommended.
“So to summarize, the guidelines are available; this is not cookbook. This is just a reference of how we can think about treating these patients,” stated Dr. Waguespack. He reemphasized that children should be sent to high-volume centers, as this will lead to better outcomes. Furthermore, doing so will enable ongoing research, allowing larger groups of patients for study.