NEW YORK -- Under new FDA regulations, all mammography facilities have to notify women of their level of breast density.

Until now, this critical piece of information wasn't required to be shared with women, and it can potentially be a lifesaver.

Breast density refers to the amount of fibrous and glandular tissue in a woman's breast compared to fatty tissue. The size of a woman's breast does not determine density, but age might: about 50% of women in their 40s have dense breasts, with percentages decreasing with age.

"The only way you can determine that is through radiology. So ... make sure that you have a mammogram, then you'll know if you have dense breasts or not," said Lorraine Frazier, dean of the Columbia University School of Nursing.

"If I have dense breast tissue, am I more prone to get cancer?" CBS News New York's Kristine Johnson asked.

"The answer is, yes, you probably are, and we don't know why, but there is a greater chance of having cancer," Frazier said.

"How important is it for a woman to know whether or not they have dense breast tissue?" Johnson asked.

"Very important. It's a gift. I really think these new regulations are a gift to all of us," Frazier said.

There are levels of density that will be reported as part of this new regulation: A, B, C and D. Women with C and D are the likely candidates for additional testing.

AI and 3-D screening, which are now far more common in mammograms, will also help with hard-to-diagnose cancers, but the most important thing is to get a mammogram.

"I never skipped a mammography ever," Frazier said. "Every year I was told that I was cancer-free, and that wasn't always the case."

It was after a screening in 2022 that Frazier was given some additional news: she had dense breast tissue.

"And did that camouflage your cancer?" Johnson asked.

"Yes," Frazier said.

Even with an all clear on her mammogram and no family history, she still felt something was wrong.

"What did you feel?" Johnson asked.

"A thickness. A thickness in my breast," Frazier said.

An MRI ultimately detected her cancer. She was told it was slow-growing and had likely been there for years.

"When you see a mammography, if your breasts are dense, it's all white, you know. And the problem is, breast cancer shows up white, also," Frazier said.

She was diagnosed with early stage breast cancer - a nurse and educator becoming the patient.

Frazier had a double mastectomy, chemotherapy and radiation.

"What was the hardest part of your journey?" Johnson asked.

"Understanding that it's not the end of the road. I know that sounds really strange," Frazier said.

"Even for a medical professional?" Johnson said.

"Even for a medical professional. You know, you hear the word cancer, and you think that's it, right? And you see the world in a different way," Frazier said.

"Has it also changed your perspective, just as a dean?" Johnson asked.

"Yes ... How do we learn to make that journey better for those patients? And that means touching someone's hand, right? I mean that's nothing, but if you're having chemotherapy and I touch your hand and say, 'Kristine, I know this is the first time for you and you know what, we're going to get through this together,'" Frazier said.

She added, "The majority of time for breast cancer, you will get on the other side. You need to hear that, and you need to see that."