Introduction: For minimally invasive surgery of primary hyperparathyroidism (PHPT), the identification of the accurate localization is required. As preoperative diagnostic imagings, we perform ultrasound, technetium 99m-sestamibi scintigraphy and either or both of megnetic resonance imaging or computed tomography in all cases. The aim of the present study is to evaluate the clinical biochemical factors that fascilitate preoperative diagnostic imagings for localization.
Methods: We retrospectively searched the medical records of patients with PHPT who were admitted in our hospital from 2014 to 2016. Fifty-five patients were identified. Four patients with parathyroid carcinoma, multiple endocrine neoplasia type 1, familial hypocalciuric hypercalcemia, and detectable parathyroid hormone-related protein were excluded. Fifty-one patients were included in the study. We defined 36 patients as the localized group, including 30 patients who underwent curative operation and 6 non-operative patients whose suspicious adenoma was consistently identified by two or more of diagnostic imagings. And other 15 patients were defined as the non-localized group. We compared biochemical data including intact parathyroid hormone (iPTH), serum calcium, urine calcium, and tartrate-resistant acid phosphatase 5b.
Results: iPTH was statistically higher in the localized group (146  vs. 98  pg/ml: p=0.010). Multivariate logistic regression analysis demonstrated that the usefulness of preoperative diagnostic imaging was ensured only in higher iPTH (p=0.014). When we set the cut-off value of iPTH to 150 pg/ml, sensitivity was 48.6% and specificity was 87.5% (AUC: 0.73 [95% CI 0.590.87]). When we used whole parathyroid hormone (wPTH) in place of iPTH, we obtained similar results: the cut-off value 85 pg/ml with sensitivity 57.1% and with specificity 87.5% (AUC: 0.84 [95% CI 0.720.96]).
Conclusion: Both iPTH and wPTH as circulating parathyroid hormone concentration are useful to predict whether preoperative diagnostic imagings can identify the acurate localization of the parathyroid adenoma.
20 May 2017 - 23 May 2017