Mammograms miss up to 75% of tumors in women with dense breasts.

Left image: Yellow arrow points to cancer.
Right image : A dense breast.
The non fatty tissue and a cancerous tumor, both look white on a mammogram.
It’s imposible to distinguish what is normal and what is cancer.

Why knowing your breast density is so important
The breast is comprised of fatty and non-fatty tissue.
The higher the precentage of non-fatty tissue, the higher the chance that a mammogram would NOT be able to detect the cancer.

It means that when a woman receives a letter saying the mammogram is normal, she at that moment might very well have breast cancer that the mammogram couldn’t distinguish. 
Unless she detects the tumor with another method, it will keep growing in the body, increasing the chances that it will kill her.

40% of women will have dense breasts throughout their lives.
Do you know your breast density?
If not ask your doctor!

Breast Density Classifications