Preoperative visualization of parathyroid pathology in patients with primary hyperparathyroidism using PAT/KT: a retrospective study

INTRODUCTION: Topical diagnosis of pathologically altered parathyroid glands in patients with primary hyperparathyroidism is a challenge both for specialists of radial diagnostics and for planning the scope of surgical intervention. The choice of diagnostic modality for localization of parathyroid glands depends on the availability of the method for a particular medical center. PET/CT is a promising method to determine the localization of parathyroid adenoma OBJECTIVE: To analyze the experience of using PET/CT with 11C-methionine and PET/CT with 11C-choline for preoperative diagnosis of parathyroid pathology in patients with primary hyperparathyroidism. MATERIALS AND METHODS: 72 patients diagnosed with PHPT and underwent surgical treatment were included in the study. Before surgical intervention all patients underwent laboratory and instrumental investigations in the scope of: blood tests for PTH, TTH, ionized calcium, calcitonin, 25(OH)D, creatinine, phosphorus, ultrasound of the neck, computer tomography of the neck with intravenous bolus contrasting. RESULTS: PET/CT showed the highest rates of DA in the patient group before primary surgery — 90.9%, compared with ultrasound (89.6%) and CT with IV contrast (84.9%). In the group of solitary adenomas of ectopic MTCS, PET/CT also had a higher DA — 92.8% than the other modalities. In patients with relapsed or persistent disease, the informativity rates of CT with intravenous contrast and PET/CT were similar (Se — 100%, Sp — 94.1%, DT — 96.2%). DISCUSSION: The algorithm for preoperative evaluation of patients to identify the location of pathologic parathyroid glands now includes imaging with two modalities: Neck ultrasound and radionuclide imaging: planar scintigraphy (washout/subtraction), SPECT, SPECT-CT. If the results are questionable, a CT scan of the neck with contrast or PET/CT is performed as a second step. None of the modalities has 100% diagnostic accuracy. Our study demonstrated the superiority of PET/CT over ultrasound and CT w/in contrast in a group of patients scheduled for primary surgical treatment. In a small group of patients, high informative rates of PET/CT and CT with contrast were demonstrated before reoperation, confirming the great potential of these techniques in these patients. CONCLUSION: PET/CT with 11C-methionine and PET/CT with 11C-choline have high diagnostic accuracy in patients with primary hyperparathyroidism before reoperation. PET/CT and CT with contrast showed similarly high diagnostic accuracy for the diagnosis of parathyroid adenoma with persistence or recurrence of the disease in patients with primary hyperparathyroidism.