LAS VEGAS – Micropapillary thyroid carcinoma may not be as indolent as generally thought, according to the findings of a retrospective study of thyroidectomy cases.
A review of 213 patients diagnosed with the cancer found that 34% of them had multifocal disease, and 14%, metastatic disease, Maggie Bosley reported at the Association for Academic Surgery/Society of University Surgeons Academic Surgical Congress.
“Although micropapillary thyroid cancer is thought to be rarely metastatic, we found that the incidence of metastasis to the central neck compartment is not negligible,” said Ms. Bosley, a third-year medical student at the Medical University of South Carolina, Charleston. “In 2% of our cases, we found metastases in the lateral neck compartment,” which required extensive neck dissection.
Ms. Bosley presented a review of 213 consecutive patients who underwent thyroidectomy from 2007 to 2015, and were found to have micropapillary thyroid cancer. She reviewed the pathology reports for tumor size, presence or absence of metastases in the central and lateral node basins, and multifocality.
Most of the patients (88%) were women, with an average age of 56 years, although the range was wide (18-89 years).
About a third of the patients (73; 34%) had multifocal disease. This was bilateral in 21 (29%). Metastasis to the central nodes was present in 31 patients (14%); 4 of these patients also had positive lateral neck node metastases (2%).
“Approximately 13% of patients with node metastasis also required selective lateral neck dissections,” Ms. Bosley said.
She noted that, in 2015, the American Thyroid Association published a set offor diagnosing and treating micropapillary cancer. The guidelines suggest that most of these cancers can be safely followed with ultrasound exams, if there is no extrathyroid extension or nodal metastasis.
“However, ultrasound surveillance [quality] is very operator dependent,” Ms. Bosley said. Technician skill “could potentially impact the quality of surveillance.”
She had no relevant financial declarations.