Exp Clin Endocrinol Diabetes 2009; 117(8): 406-412
DOI: 10.1055/s-0028-1105925
Article

© J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York

P-gp and MRP1 Expression in Parathyroid Tumors Related to Histology, Weight and 99 mTc-Sestamibi Imaging Results

F. H. Jorna1 , H. Hollema2 , H. N. Hendrikse3 , J. Bart2 , A. H. Brouwers4 , J.T.M. Plukker1
  • 1Department of Surgical Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
  • 2Department of Pathology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
  • 3Department of Clinical Pharmacology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
  • 4Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
Further Information

Publication History

received 01.11.2007 first decision 15.03.2008

accepted 19.11.2008

Publication Date:
20 February 2009 (online)

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Abstract

Objective: P-glycoprotein (P-gp) and multidrug resistance-associated protein (MRP) are membrane efflux pumps that may have a role in the kinetics of 99mTc-sestamibi (MIBI) in parathyroid tumors. P-gp and MRP1 expression in parathyroid tumors was studied and related to histology, weight and pre- and intraoperative MIBI imaging results.

Design: Patient cohort study

Setting: Tertiary referral center

Patients: Thirty-three patients underwent radioguided parathyroidectomy for primary or secondary hyperparathyroidism.

Main outcome measures: P-gp and MRP1 expression.

Methods: Dual-phase 99mTc-MIBI scintigraphy and SPECT results were compared to the surgical findings. Radioactivity and weight of resected parathyroid tumors were measured. Intraoperative radioactivity measurements were decay corrected. After routine histology immunohistochemistry was performed using C494 monoclonal antibodies to P-gp and MRP1r1 to MRP1. P-gp and MRP1 expression were scored covering both distribution of positivity and degree of immunostaining semi quantitatively.

Results: P-gp and MRP1 staining was observed in 97% and 43% of the glands respectively. P-gp staining was positive in 91% (21/23) of the adenomas and in all 36 hyperplastic glands. MRP1 staining was positive in 22% (5/23) of the adenomas and in 61% (22/36) of the hyperplastic glands. P-gp or MRP1 expression did not correlate with preoperative 99mTc-MIBI imaging or intraoperative radioactivity. Parathyroid weight was associated with preoperative MIBI imaging results and MIBI uptake measured during surgery.

Conclusion: P-gp and MRP1 expression did not correlate with 99mTc-MIBI uptake in parathyroid tumors. Parathyroid weight remains the major known factor influencing 99mTc-MIBI uptake.

References

Correspondence

J.T.M. PlukkerMD, PhD 

Prof. of Surgery

Department of Surgical Oncology

University Medical Center Groningen

P.O. Box 30.001

9700 RB Groningen

The Netherlands

Phone: 31/50/361 23 17

Fax: 31/50/361 48 73

Email: j.th.plukker@chir.umcg.nl