Shortly after publicly revealing her breast cancer diagnosis, former “The Office” actress Jenna Fischer is discussing her journey, treatment, and how her mindset has shifted.

On October 8, Fischer, 50, shared on Instagram for National Breast Cancer Awareness Month that she had been diagnosed with Stage 1 triple-positive breast cancer in December 2023. After undergoing surgery, chemotherapy, and radiation, she is now cancer-free.

In a conversation with “TODAY” co-host Hoda Kotb, Fischer expressed her hope that sharing her story would offer comfort and hope to other women facing a breast cancer diagnosis. The actress shared that she had gone for her routine mammogram appointment in October 2023, which she had been postponing.

"Three weeks later, they said, ‘Oh, your mammogram was fine. There were a few spots that were difficult to see. You have very dense tissue. We would recommend that you do another mammogram and maybe follow up with a breast ultrasound,’" she recalled.

“I was like, ‘This is the appointment that won’t end,’” Fischer added, laughing.

She explained that she felt no level of concern when returning for her breast ultrasound but was then asked to undergo a biopsy, being told there was likely a 10% chance it was cancerous. Fischer was hiking alone when she received the results through her patient portal.

“I checked the portal on the hike, and that’s when I saw words like ‘invasive,’ ‘ductal,’ ‘carcinoma,’ ‘malignant,’” she said. “And I was like, ‘Those words sound like cancer words.’”

She then called her husband, Lee Kirk, to tell him the results, though she wasn’t sure it was cancer until her doctor confirmed it later that day. When informed of her diagnosis, Fischer felt disbelief.

“I think the word that really got me was when we found out that I was triple-positive and my oncologist said chemotherapy. That was when I really lost it,” she said.

Fischer also talked to Kotb about the reality of losing her hair during chemotherapy, which was one of the side effects she was most concerned about.

“I started by having just a big bald patch down this side of my head. And I would kind of do a real elaborate comb-over,” she said, laughing. “I was like, ‘Oh, I understand why the gentlemen do this now. Yes, I can sort of pretend like that isn’t there for a while.’”

Though she considered it, Fischer never had a big shave-your-head moment. Besides styling her new part, she wore more hats and wigs during treatment.

When telling her children, Weston Lee, 13, and Harper Marie, 10, Fischer and her husband were very honest with them. “They’re 10 and they’re 13, and they were going to be living in the house while I went through this. They’re going to see it. And the biggest thing that I wanted them to know was that any ways that I seemed sick during this process were side effects of treatments. They weren’t cancer making me sick,” she said. “That distinction, I think, really put them at ease. And then we just kind of did it together. And they were amazing.”

Fischer also underwent a lumpectomy and radiation. Following her latest screenings, she is cancer-free, though she continues to take tamoxifen and Herceptin for the next year.

Fischer shared with Kotb that two key elements during her experience were maintaining a sense of humor and normalcy.

“Humor helped through all of this. And working helped. And staying in the world helped, she said. My oncology nurse, Ron, was an amazing man. ... When I started chemotherapy, he said to me, ‘Listen, I want you to get up every day, and I want you to walk. Every day. I want you to drink a ton of water. Walking and water. That’s what I want you to do. And I want you to take care of those kids. The women who get up and at it are the women who do better in my experience.’”

Fischer said some of the best advice she received was to live your life during this process while also listening to her body.

“I did that," she said. "And some days I just walked circles in my own living room. Some days I walked all around the block. But I did every day get up and do those things. And I think it made a really big difference.”

Reflecting on the year since her diagnosis, Fischer shared that a significant lesson she learned is the impact of people taking care of each other. “So many people took care of me, and my family, and my children, and I am so grateful for it — in so many small ways, she said. And the thing is, is that everybody had the right way or the perfect way to do it.”

She explained that some friends put her chemotherapy schedule on their calendars, while others sent thoughtful texts and picked her kids up from school. Her mother-in-law recorded prayers to send before treatments.

The mother of two said this journey has led her to view the world with newfound gratitude.

“I liked that people were annoyed if I was late with an email,” she said. “I liked being regarded as my old self, so to speak.”

“All of the most important things became so clear so quickly. And the cool thing is that that focus never leaves. So I will get to carry that with me now. ... I’ll say I find the world to be such a beautiful place in all of its quirkiness.”

Fischer added that everyday annoyances have suddenly become charming to her. “Like, you know, just traffic. ‘Oh, look at you, cute traffic. Look at all the people just goin’ places,’” she said. “How great that I get to sit in traffic. How cool.”

Fischer’s final takeaway from her experience is a message to all women: “Please don’t skip your mammogram appointment. Please get all the extra screenings that the doctor wants you to get.”

She attributes the success of her treatments to her early diagnosis and encourages others to book the annoying appointment. “If I had waited six more months, it could have been much worse. It could have spread. It was a very aggressive form of cancer,” Fischer said. “I’m really lucky that my cancer had not spread into my lymph nodes. It hadn’t spread anywhere else in my body.”

“My tumor was still very small, too small to feel,” she added. “That’s the thing. A self-exam would not have (caught the cancer). It really was that routine mammogram that started all of this. And I’m so grateful that I went to that appointment.”