Researchers at the University of Michigan have developed a technique to predict whether ductal carcinoma in situ (DCIS) may become aggressive. The new method, called biomarker ratio imaging microscopy (BRIM), may prevent women whose cancers would never become aggressive from receiving unnecessary treatment. The findings were published in Scientific Reports.
DCIS is a noninvasive form of early breast cancer in which abnormal cells are localized to milk ducts in the breast. In some cases, however, DCIS may become aggressive and spread to surrounding tissue, but until now pathologists have not had a way to identify which cases may become invasive. Long-term studies of DCIS cases that were untreated because they were originally misclassified as benign found that 20%–53% became invasive in the 10 years following the original diagnosis.
BRIM combines traditional techniques that pathologists use to microscopically examine DCIS tissue samples with mathematical analysis. It compares levels of different biomarkers, which can be seen as different fluorescent colors in stained tissue under a microscope.
In the study, researchers looked at biopsy samples from 23 patients with DCIS and stained each biomarker a different color. A computer then calculated the levels of different biomarkers in each pixel. The researchers used BRIM to identify samples with a high number of cancer stem cells, which are precursers to aggressive cancer cells. They found that 22% of the samples were slow-growing and nonaggressive and that those patients could avoid unnecessary additional treatment.