Minimally invasive radio-guided parathyroidectomy: long-term results with the 'low 99mTc-sestamibi protocol'

This paper reports the results of minimally invasive radio-guided surgery (MIRS) performed in a large group of 280 consecutive patients affected by primary hyperparathyroidism (PHPT) and with a high probability of being affected by a solitary parathyroid adenoma before surgery.

The probability of a solitary parathyroid adenoma was established by evaluating the patients with a single-day imaging protocol based on parathyroid double-tracer scintigraphy and high resolution neck ultrasonography. MIRS was performed successfully in 269 (96.1%) patients. MIRS consisted of a very low dose (37 MBq (1 mCi)) of Tc-sestamibi, given by intravenous injection, in the operating theatre a few minutes before surgery, thus allowing the radiation exposure dose to the patient and operating theatre personnel to be minimized (< 1.5 muSv.h to the surgeon).

No major intraoperative complication was recorded in our series. Transient hypocalcaemia was observed in 8% of patients. MIRS required a mean duration time of 33 min and a mean hospital stay of 1.2 days. Local anaesthesia was successfully performed in 71 patients, 63 of whom were elderly and with concomitant invalidating diseases contraindicating general anaesthesia. No case of disease relapse was observed during the subsequent follow-up.

MIRS using the 'low sestamibi protocol' is a safe and effective treatment in PHPT patients with a high likelihood of a solitary parathyroid adenoma at preoperative imaging.