Parathyroidectomy monitored by intra-operative PTH: The relevance of the 20 minutes end-point

OBJECTIVES: RI-PTH measurements are a prerequisite for minimally invasive parathyroidectomy, providing guidance regarding the removal of hyper-functioning tissue. Different criteria of PTH decrease, concentration and clearance were analyzed in order to predict surgical treatment. DESIGN AND METHODS: Blood samples at pre-incision, manipulation, 5, 10 and 20 min after resection, were collected from 145 patients presenting unambiguous, pre-surgical "single adenoma" diagnosis. RESULTS: The meeting of Irvin criterion would have permitted the identification of 28% uncured cases leading to 4% unnecessary neck exploration. On the contrary, we would have identified all of the uncured patients, to the detriment of 7% unnecessarily prolonged procedure by taking into account PTH drop, concentration and clearance shape at 20 min. CONCLUSIONS: The 20' end-point plays a key role in the correct determination of surgical outcome, strongly improving the possibility of adequate patient treatment. However, since the high success rate of traditional parathyroidectomy, yet not provided by RI-PTH, the utmost improvement to hyper-parathyroidism surgical treatment by RI-PTH could be achieved in pre-operative equivocal glands localization or multiglandular disease selected population to quickly guide and confirm the complete removal of all hyper-secreting tissue.