title: P-glycoprotein expression influences the result of 99mTc-MIBI scintigraphy in tertiary hyperparathyroidism.
abstract: Precise localization of parathyroid glands using 99mTc-labeled hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) scintigraphy could be affected by various biological factors. There is increasing evidence that radiotracer retention could be controlled by members of multidrug resistance (MDR) system, especially P-glycoprotein (P-gp). Since the role of P-gp in tertiary hyperparathyroidism (T-HPTH) scintigraphic studies is poorly recognized, the aim of the study was to compare the correlation between parathyroid P-gp expression and results of their scintigraphy in T-HPTH versus primary hyperparathyroidism (P-HPTH). P-HPTH (n = 19) and T-HPTH (n = 18) patients were subjected to 99mTc-MIBI scintigraphy followed by surgical treatment. The parathyroid glands were assessed in routine hematoxylin-eosin staining and P-gp expression was analyzed using immunohistochemistry. Parathyroids collected during cadaver donor multi-organ harvesting were used as a control. It has been found that P-HPTH-derived parathyroid glands with predominating adenoma morphology expressed less P-gp, as compared to P-gp-rich T-HPTH glands, mainly displaying nodular or diffused hyperplasia phenotype. This finding reversely correlated with results of 99mTc-MIBI scintigraphy. However, we did not observe any difference in P-gp expression nor scintigraphy result between nodular or diffused hyperplasia. Altogether, these data suggest that P-gp overexpression in T-HPTH could be responsible for decreased sensitivity of 99mTc-MIBI scintigraphy in those patients. Therefore, the recently proposed reduced neck exploration or limited parathyroid resection on the basis of scintigraphy could create the risk of persisted/recurrent hyperparathyroidism. However, this problem requires further study.
authors: Department of General, Vascular and Transplant Surgery, Central University Hospital, Warsaw, Poland.
authors: Witold
authors: W
authors: Chudzinski
authors: Justyna
authors: J
authors: Niderla
authors: Zofia
authors: Z
authors: Lasiecka
authors: Grzegorz
authors: G
authors: Wilczynski
authors: Barbara
authors: B
authors: Gornicka
authors: Aleksander
authors: A
authors: Wasiutynski
authors: Joanna
authors: J
authors: Maczewska
authors: Malgorzata
authors: M
authors: Kobylecka
authors: Leszek
authors: L
authors: Krolicki
authors: Magdalena
authors: M
authors: Durlik
authors: Ewa
authors: E
authors: Nowacka
authors: Maciej
authors: M
authors: Lazarczyk
authors: Piotr
authors: P
authors: Dziunycz
authors: Lukasz
authors: L
authors: Milewski
authors: Ireneusz
authors: I
authors: Nawrot
authors: Tomasz
authors: T
authors: Grzela
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000096:biosynthesis*; D000236:Adenoma / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D006801:Humans; D006961:Hyperparathyroidism / Q000145:classification / Q000000981:diagnostic imaging* / Q000378:metabolism; D006965:Hyperplasia; D007150:Immunohistochemistry; D010280:Parathyroid Glands / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D011877:Radionuclide Imaging; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi / Q000493:pharmacokinetics
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D017256:Technetium Tc 99m Sestamibi