IEEE TRANSACTIONS ON NANOTECHNOLOGY, VOL. 11, NO. 6,NOVEMBER 2012 1183 Modeling and Improvement of Breast Cancer Site Temperature Profile by Implantation of Onion-Like Quantum-Dot Quantum-Well Heteronanocrystal in Tumor Site Ahmad SalmanOgli and Ali Rostami Abstract—In this paper, we investigate one of the important pa- rameters (increase of infrared imaging sensitivity) in bioimaging applications that play a vital role (easy detection by nonsensitive detector) in the thermal imaging of breast cancer. It is known that differences in energy consumption exist for normal and abnormal tissue and that these differences lead to small but detectable local temperature changes if a tumor in the breast cancer is full grown. Infrared imaging has been used in tumor detection, but if the tumor is in the early stage of development, the common instrumentation is not sensitive enough to detect the subtle changes in temperature required for accurate diagnosis. Therefore, the disease can enter a dangerous stage of rapid growth. For detection of its early-stage progression, the onion-like quantum-dot quantum-well (QDQW) heteronanocrystal (CdSe/ZnS/CdSe/ZnS), for the first time, is pro- posed and used to increase the sensitivity of thermal detection. Indeed, the injected quantum-dots in the breast are excited by an external laser radiation source. In this study, the bioheat transfer equation is solved by the 2-D finite element approach for a simpli- fied model of a female breast and a cancerous tumor. The results of simulations will reveal that the local temperature change detec- tions considerably increased by using a new modified structure of quantum dot localized in tumor site. Index Terms—Finite element method (FEM), near-infrared (NIR), quantum-dot (QD), quantum-dot quantum-well (QDQW). I. INTRODUCTION B REAST cancer is an unmanaged and uncontrolled growth of breast cells. At first, we introduce a short review of breast cancer. Cancer occurs as a result of mutations or abnor- mal change in the genes responsible for regulating the growth of cells and keeping them healthy. Normally, the cells in our bodies replace themselves through an orderly process of cell growth: healthy new cells take over as old ones die out. But over time, mutations can turn on certain genes and turn off others Manuscript received July 27, 2011; revised June 5, 2012, July 3, 2012 and July 27, 2012; accepted August 1, 2012. Date of publication September 19, 2012; date of current version November 16, 2012. This work was supported by the Nano Ideh Pardazane ARAZ Company, TABRIZ-University of TABRIZ. The review of this paper was arranged by Associate Editor M. De Vittorio. The authors are with the Photonics and Nanocrystal Research Laboratory, University of Tabriz, Tabriz 51666-14766, Iran (e-mail: tirdad.zey@gmail.com; rostami@tabrizu.ac.ir). Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TNANO.2012.2213096 in a cell. That alters the ability of cell gains to keep dividing without control or order, producing more cells exactly like it and forming a tumor. The term “Breast cancer” refers to a ma- lignant tumor that has flourished and developed from cells in the breast. In general, only 5–10% of cancers are due to an ab- normality inherited from your mother or father. About 90% of breast cancers are due to genetic abnormalities that happen as a result of the aging process in general [1], [2]. Recently, ther- mal imaging [3]–[6] has been widely used due to availability of the high performance (high sensitivity) of infrared instruments. Also, the elements such as internal heat generator and photon amplifier can be attached to a detector to improve its sensitivity. The total amount of radiated infrared energy from the surface of an object in particular temperature can be calculated by Stefan– Boltzmann law. According to this law, for temperatures above absolute zero, the emitted energy from the surfaces of the ob- jects is directly proportional to their area. Since the emissivity of the human skin is extremely high, (about 1% of that of a black body), measurements of infrared radiation incited by the skin can be converted directly into accurate temperature values. This makes infrared imaging an ideal procedure to evaluate sur- face temperatures of the body. For many centuries, temperature changes within the human body have been used for disease di- agnosis. In particular, increase of body temperature has been used as an indicator of the progression of a disease. Infrared imaging was introduced into medicine in the late 1950s. This technique is one of the important keys to detect the temperature changes in breast cancer between normal and cancerous tumor tissue. However, because of critical depth and size of tumor, the early instrumentations were not sensitive enough to detect accurately the temperature changes and monitoring. In recent years, the sensitivity of infrared instruments has been extremely improved. Now, a small change in temperature can be reliably measured by means of the new high precise infrared detectors with a precision of about ±0.025 ◦ C. Cancer detection is one of the interesting areas that have made use of infrared imaging. In most cancerous sites, the differences in energy consumption of normal and cancerous tissue lead to small local temperature changes [7], [8]. Therefore, an accurate infrared imaging instru- ment can be used for cancer detection. Due to the diffusive nature of light in tissue, near-infrared (NIR) light can be preferred as a noninvasive means of diagnostic imaging within the human breast. Computational model-based difference methods are re- quired for functional imaging within the breast [9], [10]. These 1536-125X/$31.00 © 2012 IEEE