A recent study has offered new insights into a condition called ductal cancer in situ, or DCIS. A well-known risk factor for breast cancer patients, doctors have long debated whether or not to treat cases of DCIS. According to a report from NBC, the study adds new information to the debate, but does very little towards resolving it.

Researchers found that roughly 3 percent of women with DCIS ultimately died of breast cancer. The study also showed that the women who died after being diagnosed with DCIS underwent a wide range of treatments, with just as many not receiving any sort of treatment.

The study looked at more than 100,000 DCIS patients’ medical records over a 20-year period. They did not have access to individual details in each case.

Over the 20-year period, 517 women diagnosed with DCIS died in the study from breast cancer. Women who received their diagnosis before age 35 were 17 times more likely to die from breast cancer.

According to Dr. Steven Narod of the Women’s College Hospital and the University of Toronto, the risk of death largely depended on the size of a tumor and how aggressively if grew.

The results of the study confused many, as roughly half of the women with DCIS that received radiation treatments also later died of breast cancer. The symptoms were often undetectable, and it was often too late to treat.

According to Dr. Deanna Attai, a surgeon at the University of California Los Angeles, “Not all invasive cancers are lumps. All it takes are a few cells to burrow their way through.”

The study clearly highlights the risks of DCIS, although it oddly does not suggest that any sort of early radiation treatment has an effect on the outcome of the condition. The scientists recommend a reclassification of DCIS that encourages earlier treatments, but further studies will need to be done to determine their effectiveness.