Yonsei researchers enhance breast cancer diagnosis accuracy with blood test

Korean researchers have found a clue to improve the accuracy of breast cancer diagnosis through a blood test.

A group of researchers at Yonsei University said Tuesday that they have improved the diagnostic accuracy of mammography, the existing method of diagnosing breast cancer, by using a substance secreted by breast cancer tissue to compensate for the limitations of mammography.

The research team comprised Professors Kim Seung-il and Kim Ji-ye of the Department of Breast Surgery at Yonsei Cancer Hospital, Professor Kim Min-woo of the Department of Surgery at Yonsei University College of Medicine, and Ph. D. student Kim Yong of the Department of Medicine at Yonsei University Graduate School.

Mammography is mainly used for breast cancer screening, the number one cancer among Korean women. However, in the case of dense breasts, which have more mammary tissue than fatty tissue, there are many white areas besides cancer, making it difficult to diagnose.

The research team has developed a technology to selectively isolate substances secreted by breast cancer from the blood of breast cancer patients based on liquid biopsy, which analyzes blood to diagnose cancer and track its progress.

All cells, including cancer cells, secrete an “extracellular endoplasmic reticulum” for cell-to-cell signaling. The team identified five miRNAs in the extracellular vesicles from the patient's blood, which they named EVmiRs, and analyzed their expression patterns.

To validate the technology, they conducted a study on 120 breast cancer patients hospitalized at Yonsei Cancer Hospital, 46 patients with benign tumors of the breast, and 46 healthy people.

The results showed that EVmiR had a clinical sensitivity of 85.8 percent, a specificity of 84.6 percent, and an AUC (area under the curve) of 0.908, which measures the accuracy of diagnosing breast cancer. If the AUC approaches 1, it is considered superior, with an AUC above 0.8 being considered high performance.

In breast cancer patients with dense breasts, mammography showed a clinical sensitivity of 56.3 percent, while EVmiR had a clinical sensitivity of 84.4 percent, and the combination of the two methods increased the clinical sensitivity to 95.3 percent.

The researchers believe that EVmiR could serve as a key indicator for breast cancer diagnosis, as it was found to be consistently expressed in breast cancer patients regardless of their physical circumstances.

“By developing a technology that increases the sensitivity of breast cancer diagnosis based on the analysis of miRNAs secreted by breast cancer, we have provided a way to compensate for the limitations of conventional mammography,” Professor Kim Ji-ye said. “We will continue to improve the accuracy of early breast cancer diagnosis through further research.”

The findings were published in the international journal Theranostics.