Project: Real-time freehand SPECT imaging for image-guided occult lesion localization in breast cancer

The surgical procedures known as radioguided occult lesion localization (ROLL) and radioactive seed localization (RSL) in non-palpable breast cancer has extended the indications of radioguided surgery, while improving significantly the quality of treatment in terms of better resection margins and minimized healthy tissue extraction (e.g. [1, 2]). Currently up to 25% of all new breast cancer patients are non-palpable tumors making more than 80.000 cases per year in Europe. In up to 50% of these patients the surgical treatment will fail showing close or involved margins [1]._x000D_According to the principle of ROLL/RSL in order to localize a non-palpable breast tumor (which is detectable in ultrasound, MRI or mammography) one can replace the traditional wire marking (wire-guide localization, WGL) with the injection/implantation of a radioactive tracer (injection in case of ROLL and implantation in case of RSL). This radioactively labeled tumor can be then localized intra-operatively using a gamma probe. Thus problems and complications related to the WGL can be minimized and localization can be simplified, while dropping the rate of close or involved margins down to 10% [3]._x000D_Despite the vast experience in Italy, Spain, the Netherlands, Hungary, etc. (e.g. [3,4,5]) the ROLL and RSL procedures have however not managed to be established as a routine examination in Europe. Among the reasons are the difficulty to determine quantitatively the borders of the regions intra-operatively using only the acoustic signal of a gamma probe, the lack of 3D information and in particular depth information and the learning curve of the procedure._x000D_To tackle the problem of surgical borders in breast cancer groups have proposed the use of 2D mini-gamma cameras [6], intra-operative X-ray specimen imagers or also impendance-based systems to assess the malignancy of borders [7]. However, none of them solve complete the lack of 3D information; mini-gamma cameras do provide quantitative information; X-ray specimen imagers and impedance-based systems do not provide any feedback during the resection, but merely at the moment the tissue is already resected._x000D_In order to overcome these problems, we propose the development of a real-time 3D intra-operative imaging system for ROLL/RSL based on the principles of freehand SPECT. Freehand SPECT is a 3D intra-operative nuclear imaging modality based on gamma probe and surgical navigation technologies, which was introduced by the core team of SurgicEye in 2010 [8]. Currently there are no real-time imaging methods in Nuclear Medicine._x000D_The availability of a real-time imaging and navigation tool for ROLL/RSL can result in a break-through for the ROLL/RSL procedures, which will enable the extension of these minimal invasive and personalized procedures to a wide population and be implemented uniformly throughout Europe. The inclusion of imaging in the operating room will reduce the involved margins rate while minimizing the resected healthy tissue. The image-guidance and the availability of depth information will further enable a fast and intuitive roll-up of the procedure even for less experienced physicians._x000D_The development of a real-time freehand SPECT will involve the modelling of the workflow of ROLL/RSL and the development of protocols and its evaluation within pilot clinical trials prelude to future controlled multicentric trials not considered within this project._x000D_On the technical side, major changes are required in terms of algorithms needed to generate 3D freehand SPECT images. This has to do with the fact that the assumption of a rigid 3D image is not valid in ROLL/RSL. Completely new algorithms considering real-time update of the 3D image will be developed. From a physics perspective methods for tissue modelling in real-time will be set in order to constrain the ill-posed nature of the problem of real-time 3D freehand SPECT imaging._x000D_The availability of real-time freehand SPECT will also expand the ROLL/RSL procedures in further clinical indications like head/neck cancer, melanoma, etc. and will improve significantly the acceptance of these technologies in procedures like the sentinel lymph node procedure._x000D_Finally, as only real-time 3D nuclear imaging method, the concepts developed in this project can be used also to extend conventional SPECT or PET imaging to real-time SPECT or real-time PET expanding further the impact of the project to diagnostic procedures in fields like nuclear cardiology._x000D__x000D_[1] Lavoué et al. Ann Surg Oncol. 2008 Sep;15(9):2556-61._x000D_[2] Moreno et al. J Exp Clin Cancer Res. 2008 Aug 15;27:2._x000D_[3] Monti et al. Ann Surg Oncol. 2007 Oct;14(10):2928-31._x000D_[4] Van Riet et al. Br J Surg. 2010;97:1240–1245._x000D_[5] Besic et al. The Breast. 2009;18:294–298._x000D_[6] Paredes et al. Eur J Nucl Med Mol Imaging. 2008 Feb;35(2):230-5._x000D_[7] Pappo et al. J Surg Res. 2010 May 15;160(2):277-81._x000D_[8] Wendler et al. Eur J Nucl Med Molec Imaging. 2010 Aug;37(8):1452-61.

Acronym	Real-time fhSPECT (Reference Number: 7103)
Duration	01/07/2012 - 30/06/2014
Project Topic	Within this project a 3D intra-operative imaging system based on the freehand SPECT technology will be developed and clinically tested for the procedures of radioguided occult lesion localization in breast cancer.
Project Results (after finalisation)	In order of priority:_x000D_1. Development, implementation and validation of a world-wide new real-time freehand SPECT image generation approach with a quality close to the one needed for its integration in the products of SurgicEye._x000D_2. Understanding of the requirements for the techniques of ROLL and RSL._x000D_3. Stronger relationship with AvL, our clinical Ps in Amsterdam.
Network	Eurostars
Call	Eurostars Cut-Off 7

Project partner

Number	Name	Role	Country
2	Stichting Antoni van Leeuwenhoek Ziekenhuis	Partner	Netherlands
2	SurgicEye GmbH	Coordinator	Germany