Table of Contents
International Journal of Molecular Imaging
Volume 2012 (2012), Article ID 545034, 10 pages
http://dx.doi.org/10.1155/2012/545034
Research Article

Feasibility Evaluation of Radioimmunoguided Surgery of Breast Cancer

1Department of Medical Physics, Sunnybrook Odette Cancer Centre, 2075 Bayview Avenue, Toronto, ON, Canada M4N 3M5
2Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada M5S 3M2
3Department of Medical Imaging, University of Toronto, Toronto, ON, Canada M5S 3E2
4Department of Surgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada M4N 3M5

Received 22 August 2011; Revised 19 October 2011; Accepted 11 November 2011

Academic Editor: John Humm

Copyright © 2012 Ananth Ravi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Breast-conserving surgery involves completely excising the tumour while limiting the amount of normal tissue removed, which is technically challenging to achieve, especially given the limited intraoperative guidance available to the surgeon. This study evaluates the feasibility of radioimmunoguided surgery (RIGS) to guide the detection and delineation of tumours intraoperatively. The 3D point-response function of a commercial gamma-ray-detecting probe (GDP) was determined as a function of radionuclide (131I, 111In, 99mTc), energy-window threshold, and collimator length (0.0–3.0-cm). This function was used to calculate the minimum detectable tumour volumes (MDTVs) and the minimum tumour-to-background activity concentration ratio (T:B) for effective delineation of a breast tumour model. The GDP had larger MDTVs and a higher minimum required T:B for tumour delineation with 131I than with 111In or 99mTc. It was shown that for 111In there was a benefit to using a collimator length of 0.5-cm. For the model used, the minimum required T:B required for effective tumour delineation was 5.2 ± 0.4. RIGS has the potential to significantly improve the accuracy of breast-conserving surgery; however, before these benefits can be realized, novel radiopharmaceuticals need to be developed that have a higher specificity for cancerous tissue in vivo than what is currently available.