Women in their 40s with no family history of breast cancer still have a high rate of developing the disease, a new study reveals.

The findings support the recommendation that mammograms begin at age 40, researchers reported at the annual meeting of the Radiological Society of North America.

Researchers at the Elizabeth Wende Breast Care clinic in Rochester, New York, examined over 6,000 patient records from the past decade. Invasive cancer was diagnosed in 64 percent of women with no family history, and in 63 percent of patients with a family history of breast cancer.

“There’s been a lot of talk about who should get mammograms, especially the 40-age group, and we found these women were indeed being diagnosed with breast cancer,” said Dr. Stamatia Destounis, lead author of the paper. “And, even worse, many of the cases had spread to the lymph nodes, which means early detection is important.”

In 2009, the U.S. Preventive Services Task Force recommended that routine breast cancer screenings begin at age 50 instead of 40. The American Cancer Society recommends women get annual screenings beginning at 40.