Katie Couric 'Feeling Great' After Two Weeks of Radiation Treatment for Breast Cancer

Katie Couric is feeling "great" after 15 days of radiation treatment for breast cancer.

Appearing on the TODAY Show Monday, less than a week after revealing her diagnosis, Couric, 65, explained how she felt "lucky" to have had her cancer detected at stage 1A so that treatment could start early.

"I'm feeling great. I'm just getting over a cold," Couric told the TODAY show. "I'm feeling just fine. I finished radiation last week. They said it made you tired, I was actually not too tired from it.

"I just feel super lucky that it was diagnosed when it was," Couric continued, while stressing the need for women to have regular mammograms, without which her cancer would not have been caught so early.

Couric first shared news of her cancer diagnosis in a personal essay published on her website on Sept. 28. This revealed that she had been diagnosed with breast cancer on June 21, and had a lumpectomy on July 14. Doctors removed a tumor she said was "2.5 centimeters, roughly the size of an olive."

The journalist also shared that pathology showed the likelihood of her cancer returning was "considered low enough to forgo chemotherapy." She started her radiation on Sept. 7, with her final round occurring Sept. 26.

RELATED: Katie Couric Reveals Breast Cancer Diagnosis as She Urges Others to Get Annual Mammograms

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Speaking to TODAY Couric added that she was "stunned" to receive the diagnosis from her doctor, adding that the phrase "It's cancerous or you have cancer," really caught her off-guard.

Despite this, the journalist said she soon developed a degree of perspective about her diagnosis as a result of having lost her first husband, Jay Monahan, to colon cancer in 1998 and her sister, Emily Couric, to pancreatic cancer in 2001.

Couric's second husband John Molner also had "a tumor the size of a coconut on his liver" removed prior to their 2014 wedding, she stated in her website essay. Her mother, Elinor Couric, was also diagnosed with mantle cell non-Hodgkin lymphoma before her death from pneumonia in 2014, while her father, John Couric, was diagnosed with prostate cancer prior to his 2011 death from Parkinson's. Couric's mother-in-law, Carol Monahan, also died from ovarian cancer on Sept. 11, 1999.

RELATED: Katie Couric on Her Deeply Personal Anti-Cancer Crusade: 'Cancer Rips People Away from the Life They Could've Had'

"She (her doctor) told me it was treatable, we needed to have a plan," Couric explained on TODAY. "So I went from feeling shocked to not that shocked given my family's history, to relieved because my exposure to cancer with Jay and Emily and my mother-in-law... they were all advanced and the prognosis was really tough, so I felt so grateful, honestly."

Like all parents, however, Couric she still felt "nervous" telling her daughters, Carrie and Ellie about her diagnosis, and ended up calling them individually with the news.

"I waited a few days so I could process it and really understand what we're dealing with. And I FaceTimed each of them," she said. "I was very reassuring, but I saw in their faces. It's just hard to deliver that news no matter how you do it."

Couric is now urging other women to get regular mammograms and is in talks with Rep. Rosa DeLauro, D-Conn., who is pushing legislation that requires insurance companies to cover ultrasounds for women with dense breasts so that patients do not pay extra costs.

"All these breast cancer diagnoses would happen much earlier if, in fact, women with dense breasts had breast ultrasounds," Couric said Monday.

RELATED: Inside Katie Couric's Longtime Cancer Prevention Advocacy: 'My Personal Mission'

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Couric has co-founded several research and charity organizations to fight cancer. Nearly 15 years old, Stand Up To Cancer, an initiative created to accelerate innovative cancer research, has already brought in $746 million from fundraising efforts.

Following her first husband's death, Couric famously used her nationwide platform to raise awareness of the importance of getting checked for colon cancer by having a colonoscopy on-air on Today. Years later, she took Jimmy Kimmel to get a colonoscopy on camera in 2018.

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"Cancer has had a huge impact on me personally, having lost my husband, Jay, in 1998 from colon cancer and my sister, Emily, two years later from pancreatic cancer," Couric previously told PEOPLE. "I think the most powerless feeling you have is not being able to help someone you love conquer this disease."