The Role of Bilateral Neck Exploration for Primary Hyperparathyroidism in the Minimally Invasive Parathyroidectomy Era

OBJECTIVES: In recent years, together with the contribution of new imaging methods, minimally invasive parathyroidectomy (MIP) has become the standard procedure in selected patients with the primary hyperparathyroidism (pHPT). However, some patients may still need bilateral neck exploration (BNE). In this study, we aimed to evaluate the factors associated with the necessity of BNE. METHODS: Data of the patients, operated by same single surgeon in between 2010 and 2019, were evaluated retrospectively. Patients were divided into two groups as MIP group (group 1) and BNE group (group 2). The risk factors associated with necessity of BNE were evaluated. RESULTS: Three hundred and forty-four patients (288 females and 56 males) were included in study. The mean age was 54.1±12.8. Pre-operative parathormone level (288 pg/mL vs. 190 pg/mL, p<0.001; respectively), compatible, inconsistent and negative imaging on scintigraphy (82.5% vs. 28.7%, 9.6% vs. 19.1, 7.9% vs. 52.25%, p<0.001; respectively), compatible, inconsistent and negative imaging in ultrasonography (USG) (72.9% vs. 20%, 7% vs. 19.1%, 20.1% vs 60.9%, p<0.001; respectively) in combination of USG and scintigraphy, two positive, single positive and negative imaging (72.5% vs. 11.3%, 25.8% vs. 55.7%, 1.7 vs. 33%, p<0.001; respectively), single adenoma, double adenoma, hyperplasia rates in pathology (96.1% vs. 79.1%, 3.1% vs. 12.2%, 0.9% vs. 8.7%, p<0.001; respectively), concomitant thyroidectomy (11.4% vs. 38.3%, p<0.001; respectively), diameter of the removed gland (2.03 vs. 1.58 cm, p<0.001; respectively), and volume of the removed gland (2.27 vs. 1.22 cm(3), p<0.001; respectively), were significantly different in group 1 compared to group 2. Low pre-operative parathormone, discordant pathological gland localization compared to pathological gland compatible with scintigraphy images (odds ratio [OR]: 3.690; p=0.027), negative scintigraphy images (OR: 9.174, p=0.000), and need for additional thyroidectomy (OR: 5.067); p=0.000) were determined as independent risk factors increasing the need for BNE in the multinomial logistic regression analysis. Long-term cure rates were similar (98.3% vs. 94.8%, p=0.079; respectively). CONCLUSION: At present, BNE may be necessary in the surgical treatment of a significant proportion of patients with pHPT. According to our results, the possibility of BNE requirement is higher in patients with low PTH level compared to pre-operative high PTH values, in patients with discordant and negative scintigraphy compared to positive and compatible scintigraphy, and in patients who will undergo additional thyroidectomy. We think that BNE is not an alternative to MIP, but an effective option that is complementary to MIP to achieve optimal results in parathyroid surgery.