Estimation of Size and Depth of a Breast Tumor Using Thermal Analysis; A Numerical Study

As the most common type of cancer in women, breast cancer has a high death rate. One effective way to lower this rate is by breast screening. Thermography is used as a non-invasive, painless, non-contact, and cost-effective method to show breast abnormalities and lesions. A breast tumor generates more heat than normal tissue, which affects the skin temperature and can be quantified by thermal patterns. In this study, in order to assess the temperature distribution in a breast with a tumor, an axisymmetric finite element model was presented. The tumor metabolism rate was considered according to its grade. A parametric study was conducted to investigate the surface temperature distribution according to the size and location of the tumor. The maximum observed temperature difference was 1.3°C, which can be fully recognized by thermal imaging. The temperature difference drops from 0.93 to 0.14°C when the tumor’s depth rises from 20 to 35 mm. The results showed that the tumor’s location and size can be estimated by considering the two main features of the maximum temperature difference on the surface of the skin and circumferential distance from the axis of symmetry where the temperature differential equals half of its maximum. Also, the effect of blood perfusion rate on temperature distribution was analyzed. The temperature differential at the axis of symmetry increased from 0.50 to 0.82°C when the blood perfusion rate was increased four times. A transient process was used to analyze the impact of employing a cooling load and investigate the thermal recovery profile. In the recovery phase, the maximum temperature difference was 0.6°C between normal and cancerous breasts, and after 10 minutes, the temperature contrast stabilized. The results of this study showed that, although thermography and thermal analysis are not known as the most accurate diagnostic tools, they can be useful tools in the early and non-invasive screening of breast abnormalities.