Role of the parathyroid subtraction scintigraphy in the management of secondary hyperparathyroidism. Apropos of 33 cases

Aim: 99mTc-Sestamibi is used in the imaging of hyperparathyroidism in order to guide the surgical procedure and to propose methods of less invasive surgery. The aim of our study was to evaluate the efficiency of preoperative subtraction parathyroid scintigraphy (Sestamibi- 99mTc/Pertechnetate) in the management of secondary hyperparathyroidism. Patients and methods: The records of 33 patients with renal impairment consecutively operated from 2009 to 2011 for secondary hyperparathyroidism were retrospectively reviewed. We collected data on parathyroid function, results of parathyroid scintigraphy, intraoperative findings and pathological findings. Results: Scintigraphy was positive in 32 patients by disclosing a total of 75 hyperplastic parathyroid glands. The surgical exploration of all parathyroid glands revealed 99 hyperplastic glands confirmed by histological analysis. The sensitivity of parathyroid scintigraphy was 70.7% with a specificity of 85%. Positive predictive value was 93.3%, while negative predictive value was 50%. No correlation was found between the values of parathyroid hormone (PTH) and calcemia measured preoperatively and scintigraphic results. Discussion and conclusion: In our study, the correlation of scintigraphic data with PTH and serum calcium is not statistically significant. However, owing to a high positive predictive value, the parathyroid scan should be indicated. Value of parathyroid scintigraphy extends to searching ectopic or supernumerary glands and especially in cases of persistent or recurrent hyperparathyroidism. © 2012 Elsevier Masson SAS.