JNM
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH RSS TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

First published online October 16, 2009, 10.2967/jnumed.109.064980
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
jnumed.109.064980v1
50/11/1785    most recent
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Related articles in JNM
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Google Scholar
Right arrow Articles by Saggiorato, E.
Right arrow Articles by Orlandi, F.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Saggiorato, E.
Right arrow Articles by Orlandi, F.
Journal of Nuclear Medicine Vol. 50 No. 11 1785-1793
© 2009 by Society of Nuclear Medicine
doi: 10.2967/jnumed.109.064980

Clinical Investigation

99mTc-MIBI Imaging in the Presurgical Characterization of Thyroid Follicular Neoplasms: Relationship to Multidrug Resistance Protein Expression

Enrico Saggiorato1, Tiziana Angusti2, Rosy Rosas3, Morena Martinese1, Monica Finessi1, Federico Arecco1, Edoardo Trevisiol2, Nicoletta Bergero4, Barbara Puligheddu1, Marco Volante3, Valerio Podio2, Mauro Papotti3 and Fabio Orlandi1

1 Section of Endocrinology, Division of Internal Medicine, Department of Clinical and Biological Sciences, Gradenigo Hospital, University of Turin, Turin, Italy; 2 Division of Nuclear Medicine, Department of Clinical and Biological Sciences, San Luigi Hospital, University of Turin, Turin, Italy; 3 Division of Pathology, Department of Clinical and Biological Sciences, San Luigi Hospital, University of Turin, Turin, Italy; and 4 Department of Anesthesiology and Intensive Care, San Giovanni Battista Hospital, University of Turin, Turin, Italy

Correspondence: For correspondence or reprints contact: Enrico Saggiorato, Section of Endocrinology, Division of Internal Medicine, Department of Clinical and Biological Sciences, Gradenigo Hospital, University of Turin, c.so Regina Margherita 10, 10153 Turin (TO), Italy. E-mail: enrico.saggiorato{at}unito.it

Recently, thyroid 99mTc-methoxyisobutylisonitrile (99mTc-MIBI) scintiscanning has been proposed in an attempt to preoperatively identify thyroid malignancies, but discrepant results have been reported for oncocytic lesions. The aim of this study was to investigate the usefulness of visual and semiquantitative analyses of 99mTc-MIBI scintigraphy for preoperatively characterizing thyroid nodules with indeterminate cytologic diagnoses, segregating in advance nononcocytic variants from those that are oncocytic. This study also aimed to analyze the relationship between 99mTc-MIBI images and P-glycoprotein (P-gp)/multidrug resistance-associated protein-1 (MRP1) immunohistochemical expression. Methods: Fifty-one consecutive patients with cold thyroid nodules cytologically diagnosed as nononcocytic or oncocytic follicular neoplasm were prospectively studied. Visual and semiquantitative 99mTc-MIBI scanning was performed and the diagnoses of the lesions were histologically proven by subsequent thyroidectomy. Immunohistochemical evaluation of P-gp and MRP1 was also performed on surgical samples. Results: Visual and semiquantitative 99mTc-MIBI scintiscans showed a low specificity in preoperatively discriminating malignant oncocytic lesions. In nononcocytic nodules, the semiquantitative method was more accurate than the visual (94.44% and 77.78%, respectively). P-gp protein expression was negative in all thyroid lesions, whereas apical plasma membrane MRP1 expression was found in 78% of the lesions with a negative 99mTc-MIBI retention index, compared with 11% of lesions with a positive retention index, correlating most strongly with a negative 99mTc-MIBI RI in those cases with strong MRP1 apical expression. Conclusion: Semiquantitative 99mTc-MIBI scintigraphy is an adjunctive method to predict preoperatively the malignant behavior of nononcocytic follicular thyroid nodules indeterminate at fine-needle aspiration biopsy, with a potential impact on the definition of their clinical management. Moreover, the good correlation found between immunohistochemical apical expression of MRP1 and the scintigraphic findings supports the 99mTc-MIBI results and provides tissue information on the molecular mechanisms responsible for 99mTc-MIBI images in thyroid lesions.

Key Words: thyroid follicular neoplasms • thyroid 99mTc-MIBI scintigraphy • fine-needle aspiration biopsy • P-glycoprotein • multidrug resistance–associated protein-1

COPYRIGHT © 2009 by the Society of Nuclear Medicine, Inc.


Related articles in JNM:

This Month in JNM

JNM 2009 50: 11A-12A. [Full Text]  





HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH RSS TABLE OF CONTENTS
JOURNAL OF NUCLEAR MEDICINE TECHNOLOGY THE JOURNAL OF NUCLEAR MEDICINE
Copyright © 2009 by the Society of Nuclear Medicine.