By Kristina Rebelo
SAN DIEGO -- October 7, 2009 -- Pre-excisional intraoperative parathyroid hormone (iPTH) levels are not predictive of parathyroid adenoma mass, according to researchers presenting at the American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF) Annual Meeting 2009.
In a retrospective study that reviewed 71 patients (aged 56.5 +- 14.2 years; 16 men) who were undergoing parathyroid resection from January to December 2006 at a tertiary institution, researchers found that PTH levels were not consistent with adenoma size.
"You would think it would be the inverse," said David Shamouelian, University of California, Los Angeles (UCLA), Los Angeles, California, on October 5. "With elevated levels of PTH, you would have a large parathyroid gland that would be easier to localise during the surgical procedure."
The average mass of resected adenomas was 1.04 +- 1.55 g. Average pre-excisional iPTH value was found to be 196.41 +- 189.00. The Pearson correlation coefficient was 0.196 (P = .101).
Researchers said the results represented an obviously poor relationship between parathyroid adenoma mass and pre-excisional iPTH levels.
According to Shamouelian, the study was able to get such a large population in 1 year because UCLA was a surgical centre in a large metropolitan area. He attributed the high number of adenoma masses primarily to germ line mutations of the MEN1 gene, found in >85% of multiple endocrine neoplasia type 1 patients, and germ line mutations of the RET gene, found in >95% of MEN2 patients; parathyroid hyperplasia is seen in >90% of MEN1 and about 15% of MEN2A patients.
An increasing body of published literature documents the study findings, noted Shamouelian.
[Presentation title: Does Size Matter? The Relationship Between Parathyroid Adenoma Mass and Intra-Operative PTH Values. Abstract SP169]
E-Mail this DGDispatch to a colleague
