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Katie Couric announced her breast cancer diagnosis in an Instagram post on Wednesday. The veteran journalist revealed she was diagnosed with breast cancer after discovering a lump in her breast in June.

The 65-year-old mom-of-two underwent a lumpectomy in July and began chemotherapy and radiation treatments that ended last week.

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In a lengthy essay on her website titled “Why NOT Me?” Couric recalled the day she got her biopsy results.

“When I called back, Dr. Drossman picked up right away,” Couric writes in the essay.

“‘Your biopsy came back. It’s cancer. You’re going to be fine but we need to make a plan.’ I felt sick and the room started to spin. 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… What does this mean? Will I need a mastectomy? Will I need chemo? What will the next weeks, months, even years look like?”

She said her diagnosis brought back memories of her late husband Jay Monahan, who died from colon cancer in 1998.

“The heart-stopping, suspended animation feeling I remember all too well came flooding back: Jay’s colon cancer diagnosis at 41 and the terrifying, gutting nine months that followed,” she writes.

“My sister Emily’s pancreatic cancer, which would later kill her at 54, just as her political career was really taking off. My mother-in-law Carol’s ovarian cancer, which she was fighting as she buried her son, a year and nine months before she herself was laid to rest.”

Couric urged women over 40 to get their yearly mammogram – preferably a 3D mammogram to decrease the chance of a call back.

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