Changes introduced by intra operative quick parathyroid hormone assay in the surgical management of hyperparathyroidism.

At the beginning of the 90’s the quick intraoperative Parathormoneassay (Nichols or Future Diagnostic) has entered as routine in theoperative theaters. This has provoked a deep change in the behaviourof surgeons toward parathyroid pathology.Primary HPT. A 50% fall of the initial values of PTH is judgedsatisfactory for the definitive resolution of a parathyroid pathology.However, according to our experience, in presence of a multiglandulardisease, a problem of data interpretation exists. In our experienceof 727 cases, we have observed 84 double adenomas (11.5%),72 hyperplasias (9.9%), including 18 MEN. We performed a quickintraoperative PTH assay in 284 cases during the last 5 years. Thecut-off is optimal for the good result of the intervention when it is atleast 50% after 10 minutes of the removal of the adenoma, but clinicalexperience remains very important in difficult cases. In thesecases, a normalization of the PTH is necessary to be certain of thegood results of surgery.Secondary and tertiary Hyperparathyroidism. The quick intraoperativePTH assay is also useful, in these cases, to prevent or toreduce the persistences and the recurrences of the disease. The bestcut-off is still controversial. A retrospective study based on 448patients operated on from 1995 to 2003 (360 HPT II and 88 HPTIII) has been made : quick PTH assay was used in 241 patients. Wethink that it is useful to avoid a persistence of the disease, not onlyin the reoperations, but also during the first intervention. The opt imalcut-off should be 81% for the secondary HPT (in the particularlydifficult cases with more than two samples, 82%) while for thetertiary HPT a 50% fall is satisfactory (except in particularly complexcases where it is necessary to consider a 68% fall).