A new thermography-based approach to early detection of cancer utilizing magnetic nanoparticles theory simulation and in vitro validation Arie Levy, MSc, Abraham Dayan, PhD, Moshe Ben-David, PhD, Israel Gannot, PhD ⁎ Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel Received 29 October 2009; accepted 20 June 2010 Abstract This work describes the utilization of tumor-specific magnetic nanoparticles together with an alternating magnetic field as a means to thermally mark a tumor so as to detect it using a thermal imaging system. Experiments were conducted using an in vitro tissue model, an inductive heating system, and an infrared camera. The thermal images, recorded by the infrared camera during the experiments, were analyzed using an algorithm that was developed as part of this work. The results show that small tumor phantoms (diameter of 0.5 mm) that were embedded under the surface of the tissue phantom (up to 14 mm below the surface) can be detected and located, indicating that the proposed method could potentially offer considerable advantages over conventional thermography and other methods for cancer early detection. Nevertheless, several issues should be clarified in future studies before the method can be offered for clinical use. From the Clinical Editor: Tumor-specific magnetic nanoparticles exposed to an alternating magnetic field provide a method to thermally mark a tumor for detection using thermal imaging systems. In-vitro tissue model experiments demonstrated that tumor phantoms of 0.5mm up to 14mm below the surface can be detected and located, indicating that the proposed method could offer considerable advantages over conventional thermography. © 2010 Elsevier Inc. All rights reserved. Key words: Thermography; Magnetic nanoparticles; Antibody targeting Cancer is a world epidemic, claiming the lives of more than 500,000 people each year in the United States alone. 1 Early detection of cancer can significantly improve the patient's chances of survival. 2 In most cases cancer is detected using an imaging method [e.g., mammography, computed tomography, magnetic resonance imaging (MRI)]. However, there are several disadvantages associated with the current methods; chief among these are the lack of sufficient sensitivity and specificity, high costs, and significant health risks. Therefore, considerable efforts are being invested to improve the performance of the present imaging modalities. Thermography was proposed more than five decades ago as a cost-effective tool for early detection of breast cancer. 3 Thermography can detect cancer according to temperature differences on the skin surface as a result of the presence of an embedded cancerous tumor. This temperature increase is generated mainly by increased metabolism and blood perfusion in and around tumors 4 and can be detected using an infrared (IR) camera, which is utilized for remote measurement of the patient's skin temperature. The thermal images acquired by the IR camera are analyzed by an expert radiologist so as to detect thermal patterns that can indicate the presence of an embedded tumor. The radiologist can also be aided by image analysis tools. Thermography can offer several considerable advantages 4 : it is radiation and contact free, and it is a relatively low-cost approach. However, thermography has several considerable disadvantages when compared to other early cancer detection methods (e.g., mammography), including its relatively low sensitivity for deep and small tumors, 4 its inability to distinguish tumors from natural qhot spotsq (e.g., local inflammation), and its reliance as a subjective method on the radiologist's skills to interpret the IR images. Because of these disadvantages and other factors, thus far thermography has failed to gain full acceptance as a primary tool for cancer screening. Numerous studies have tried to improve thermography performances by using various image analyses, algorithms, and other approaches, such as asymmetry analysis 5 and dynamic thermography. 6 However, tumor-specific thermal markers have not yet been proposed as a means for improving thermography performance. The current work suggests using tumor-specific magnetic nanoparticles (MNPs) as such thermal markers so as to improve the current tumor detection ability of thermography. MNPs are BASIC SCIENCE Nanomedicine: Nanotechnology, Biology, and Medicine 6 (2010) 786 – 796 Original Article www.nanomedjournal.com No conflict of interest was reported by the authors of this article. ⁎ Corresponding author: Department of Biomedical Engineering, Tel Aviv University, Levanon St., Tel Aviv 69978, Israel. E-mail address: gannot@eng.tau.ac.il (I. Gannot). 1549-9634/$ – see front matter © 2010 Elsevier Inc. All rights reserved. doi:10.1016/j.nano.2010.06.007 Please cite this article as: A. Levy, A. Dayan, M. Ben-David, I. Gannot, A new thermography-based approach to early detection of cancer utilizing magnetic nanoparticles theory simulation and in vitro validation, Nanomedicine: NBM 2010;6:786-796, doi:10.1016/j.nano.2010.06.007