Breast cancer is one of the major causes of death for women. Temperature measurement is advantageous because it is non-invasive, non-destructive, and cost-effective. Temperature measurement through infrared thermography is useful to detect changes in blood perfusion that can occur due to inflammation, angiogenesis, or other pathological causes.

In this work, we analyzed 206 thermograms of patients with suspected breast cancer, using a classification method, in which thermal asymmetries were computed, the most vascularized areas of each breast were extracted and compared; then these two metrics were added to yield a thermal score, indicative of thermal anomalies.

The classification method based on this thermal score allowed us to obtain the test sensitivity of 100 %, specificity of 68.68 %; a positive predictive value of 11.42 % and negative predictive value of 100 %.

Thermography imaging

These results highlight the potential of thermography imaging as an adjunctive tool to mammography in breast cancer screening. A classification of thermographic images for breast cancer detection was performed by an automated program.

A total of 206 patients were considered for test screening with clinical evidence of a tumor risk factors for breast cancer, BI-RADS classification of mammography, clinical diagnosis and pathology results of the biopsy.

The analyzed thermograms were classified as healthy (< 2.5 thermal scores) or with an abnormality (≥ 2.5 thermal scores). The findings revealed that patients who were classified as healthy, positively indicated a healthy state (automated program) with a sensitivity of 100 % and a specificity of 68.68 %.

In contrast, the same images analyzed qualitatively by an expert showed a sensitivity of around 87.5 % and specificity about 56 %, thus, our results showed a significant improvement over a manual procedure.

Furthermore, an automated method to analyze thermograms was implemented, increasing the sensitivity and specificity of the test under study. The main goal of it will be to help experts by assisting them with a better screening tool or even gives the possibility that someone without experience may benefit from the test results.

The authors emphasize that infrared thermography is not intended to replace mammography, but it is an excellent primary method/technique prior to subjecting patients to x-rays. It could be envisioned as a complementary diagnostic method to improve breast cancer detection.