“I felt sick and the room started to spin,” the former TODAY show co-anchor writes. “I was in the middle of an open office, so I walked to a corner and spoke quietly, my mouth unable to keep up with the questions swirling in my head.”

Couric went in for her routine mammogram in May, videoing her experience as a way to encourage others to get their screenings, something she has done with other routine testings to raise awareness. Her doctor informed her that she was six months late for the screening.

After the mammogram, Couric needed additional screening because of her dense breast tissue, something, she writes, she has done before. Couric’s doctor explained they wanted to follow up on what could have been “scar tissue” on her breast ultrasound from a previous breast reduction. After further testing, the doctors found a tumor, which was later found to be the size of an olive, and diagnosed her with stage 1A breast cancer. 

Mammograms miss roughly 1 in 8 breast cancers, and women with dense breast tissue, like Couric, are more likely to see a false-negative result, according to the American Cancer Society.

Cancer runs in Couric’s family: her mother had lymphoma and her father had prostate cancer. Her husband also died from colon cancer in 1998.

“My reaction went from ‘Why me?’ to ‘Why not me?” she wrote. 

Couric decided to have a lumpectomy, or surgery to remove the tumor, on July 14. The surgery was successful, which was followed by radiation that ended this week, she notes. 

If there’s one thing to take away from her experience, it’s to get screened for the cancer that takes almost 42,000 women’s lives each year. For those at-risk for breast cancer (which includes having dense breast tissue), recommendations say to get annual screenings beginning at 40. 

An alarming 22% of women between the ages of 35 and 44 have never gotten a mammogram and have no plans to, according to a new survey released this week. 

“Please get your annual mammogram. I was six months late this time. I shudder to think what might have happened if I had put it off longer,” Couric writes. “But just as importantly, please find out if you need additional screening.”