Katie Thurston is sharing positive news amid her cancer journey.

The former Bachelorette star, whose diagnosis has progressed to stage four metastatic breast cancer since originally announcing her diagnosis in February, said the first scan following her cancer treatment plan revealed that her tumors have shrunk.

"Today the scans confirmed the tumors are SHRINKING!!" the 34-year-old wrote in her July 7 Instagram post, continuing, "This is amazing news and I am so relieved!"

Although her treatment seems to be going well so far, Katie explained that it actually took her months to seek help and get her treatment started.

"I was diagnosed almost five months ago with #breastcancer. But if I’m being honest, I found the lump maybe 12 months ago," she wrote. "I was 33 years old with no family history. Why would I ever suspect #cancer - but it was."

Ultimately, this led her to have to make many decisions very quickly, and she had to adapt as her disease progressed. While she waited to pursue IVF and then to join a clinical trial, she ultimately had to reroute as her cancer became stage four. 

"People don’t realize , as it stands now, I’ll be on a treatment plan for life. There isn’t a cure for breast cancer," she wrote. "But as long as funding for medical research continues, especially for #metavivors , then we have a chance at continuing a long healthy life."

Leading up to the important scan last week, Katie shared how she had been feeling.

“July 7 is my big check-in scan to see how the meds are working with my tumor,” Katie explained in a July 3 Instagram video. “Good news would be either no growth or even shrinkage.”

She continued, "When those monthly scans or appointments come and go, I allow myself the next 28 days to really forget that I have cancer."

Katie, who was on a Greek vacation with husband Jeff Arcuri during the update, continued, “I think cancer is a trained mindset of, I don’t want to say optimism necessarily, but you have to shift how you think.”

She added, “Here in Greece on vacation, I enjoyed wine, I enjoyed the desserts, I enjoyed the memories that I’m making, because what’s the point of not living when you’re given today, when you’re given life?”

For more on Katie's journey, read on.

Katie Thurston grew concerned when she discovered a small lump in her breast during the summer of 2024."I discovered it myself," The Bachelorette alum wrote on her Instagram Stories in February 2025. "Thought maybe it was my period. Maybe it was muscle soreness from working out."Because Katie had a benign cyst removed from that same breast when she was 20, she assumed this new lump was something similar. But after it didn't go away, she decided to get it checked out."Went to the doc thinking it was going to be nothing," she continued. "I was wrong."

Katie's doctor referred her to a specialist to get a breast ultrasound. Then, she had a mammogram followed by a biopsy."Only then can they confirm if it’s breast cancer," she said in a March 18, 2025 Instagram video. And she'll never forget the moment she first got the news.It was "the worst feeling I’ve ever felt," the reality star, whose family doesn't have a history of breast cancer, shared on Good Morning AmericaMarch 19, 2025. "You’re so devastated. It’s so shocking. As a 34-year-old woman, you're not prepared."Katie informed her fans of her stage 3 diagnosis on February 15, 2025."I experienced a range of emotions over the past two weeks," she wrote on Instagram. "Despair. Anger. Sadness. Denial. And then strength. Purposeful. Ready. I cried a lot."And she expressed her intent to document her journey in the hope of helping others."One thing I did early on was search other stories like mine," she continued. "Other young women with breast cancer. Invasive ductal carcinoma. Mastectomy. Pregnancy after breast cancer. All of their stories helped. So I intend to be the same for others. This is day one of sharing and is going to be a long one. This first step of acceptance of my reality was the hardest. But I am ready to fight this."

News of Katie's diagnosis came five months after she got engaged to Jeff Arcuri, a comedian she met through Instagram in the spring of 2024."We thought we’d be planning a wedding," the TV personality continued on GMA. "We thought we’d be trying for a baby. Instead, we know that this year is really dedicated to treatment and getting better."So, Katie and Jeff froze embryos in case her cancer treatments affected her fertility. "We retrieved 17 eggs and attempted to fertilize them,"  she wrote on her Instagram Stories March 31, 2025. "Of the 17, only 6 were successfully fertilized. But then they have to make it to the blastocyst stage. Only three made it. And after genetic testing, we have 2 embryos we were able to freeze, one Grade B and one Grade C. This is the reality of IVF."Katie also spoke about the possibility of using a surrogate down the line."Jeff and I discussed the importance of my health and that when the time comes, surrogacy will likely be the best option for us," she wrote on her Instagram Stories. "A friendly reminder to stop judging celebrities who pursue surrogacy because you don't know what they have going on in their personal lives."However, Katie told GMA she and Jeff are "also OK being a childless couple."

Katie and Jeff also moved forward with their plans to wed on March 22, 2025 in New York, the bride having made the cross-country move after months of dating long-distance."It was so so sweet," she told Us Weekly about their decision to have a ceremony, sharing it took place in the backyard of their apartment with their parents, officiant and newly adopted dog Charlie in attendance. "Obviously, we were wanting to plan a wedding and there’s a lot of emotions that come in with chemo and the impact and the health. We don’t know what the next year looks like. And one night he said, 'I want to show you that I still love you and that I’m here to stay.' And he said, 'I'll get married to you tomorrow.'"And while they plan to have a big wedding in the future, she added that Jeff's gesture was him "proving that he’s here to stay" in sickness and in health. For the groom, there was also a practical element to saying "I do." "I also just want to be able to be in the hospital with her and just be like, 'My wife’s in there,'" he told the outlet. "There’s more power to that. I don’t want to be not with you for any of this."

Less than a week after Jeff and Katie wed, she shared that a PET scan detected "some spots" on her liver and that her cancer is now stage 4."I know stage 4 can sound very scary and it can be," she said in an Instagram video March 28, 2025. "But given that I am triple-positive and the spots on my liver are fairly small and detected early, I feel very optimistic on my outcome."

After receiving her stage 4 diagnosis, Katie gave an update on her treatment plan."The cancer that is within the liver is from the breast cancer," she shared. "So in basic terms, my breast cancer is the root and will be the focus. Six rounds of chemotherapy to start."But right before Katie was scheduled to begin this treatment, she received another update."Today I was supposed to start chemo," she wrote on Instagram April 4, 2025. "I had my cold cap, my cold socks, snacks, blankets, medications, entertainment ready. My aunt Lindsey flew in to be with me this weekend for recovery. However, yesterday I got the call that my pathology results on my liver, breast, and lymph nodes all came back as HER2 Negative even though my original samples as Kaiser were HER2+. I was minutes away from taking my steroid for chemo prep. Instead I am headed to my doctor to discuss how this happened, what testing is needed, and what this means for my new treatment plan."As a result, Katie noted it "sounds like chemo is off the table now." "I should be excited about that," she added. "But in two months, I’ve continued to get an updated diagnosis three times. I think thoroughness and getting a second medical opinion has been instrumental in my early cancer stage journey."

As Katie continues her fight against cancer, she's taking things day by day."Sometimes I think 'wtf is my life?’" she wrote on her Boobie Broadcast channel March 31, 2025. "But whether I like it or not, this is my life and I have to make the best of it. They say live like you’re dying, but now that I am, it’s easier said than done. And don’t get me wrong, every day, we are all closer to death. Not in a morbid way but in the undeniable circle of life. So cancer or not, I am blessed with today. So while I have sad moments or days, I want to do my best to cherish my time, cancer or not."And she's sending her followers an important reminder. "Don’t wait. Be proactive. Get checked out," Katie said on Good Morning America. "You could be doing yourself a favor in the future."

Nearly two months in treatment, Katie shared another new reality. 

“I’m losing my memory,” she wrote in a June 1, 2025 Instagram. “Going through customs and them being like, ‘Where are you coming from?’ And I looked at him and I was like, ‘I don’t remember. I don’t remember.’”

She also shared getting into a "little disagreement" with her husband—but wasn't able to fully remember the details. 

“I was like, ‘This has happened before,’” she recalled of telling Jeff. “He was like, ‘When?’ I was like, ‘I don’t know but I know it has!’”

“We’re able to laugh about it now,” she added. “Cancer is s--t. Sometimes I’m like, ‘Stop feeling bad for yourself.’ Other times I’m like, ‘You’re allowed to feel bad for yourself. Cancer f--king sucks.’”

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