Bachelorette's Katie Thurston Reveals How She 'Discovered' Her Breast Cancer

After The Bachelorette alum revealed the news that she has breast cancer on Saturday, she shared more details about her diagnosis on her Instagram Stories while answering questions from her fans.

During the Q&A, Thurston, 34, recalled how she found out about her breast cancer, saying that she "discovered it" herself.

"I had a small lump in my breast, around the 10'oclock spot," she wrote in response to a fan's questions. "I discovered it myself. Thought maybe it was my period. Maybe it was muscle soreness from working out. But, eventually, this lump never went away."

"I once had a benign cyst removed from that same breast and thought maybe it was that again. Went to the doc thinking it was going to be nothing," she added. "I was wrong."

The reality star shared in another slide that her lump is "painful," admitting that because of her pain she didn't believe it was anything serious.

"Mine is painful. Which probably led to more doubt and delay on getting it checked out as lots of sites will say 'most breast cancers don't hurt,'" Thurston said. "I thought it was PMS or working out."

She went on to answer a question about what her lump feels like. Thurston said that the benign cyst she had previously "felt like a pea or marble," yet "hard" and "unnatural," but didn't cause her "discomfort." As for the current lump, Thurston said, it felt "larger" like maybe a "ping pong ball."

"The pain initially came and went. But maybe after 3-4 months of it not going away or improving, I got nervous and saw my doctor," she added.

In another slide, Thurston shared a photo of a selfie of herself wearing a hospital gown "before knowing my life was going to change," writing that she underwent a breast ultrasound, followed by her "first mammogram" and "multiple biopsies," which ultimately revealed her diagnosis.

Thurston also revealed in her Stories that she's still "waiting" to confirm "what stage" breast cancer she has. "Getting a biopsy on my lymph node which will tell me more," she wrote, adding that she learned in the past that she does not carry the BRCA gene, but said she plans on "doing updated genetic testing soon to know for sure."

"My family doesn't have a history of breast cancer," Thurston added.

On Saturday morning, the Bachelor Nation star announced that she had been diagnosed with breast cancer, sharing the news in an Instagram post.

"Life update: I have breast cancer. Yesterday I saw all the couples post their Valentines Day celebrations. I felt envious if I'm being honest. Jeff took me to Hawaii and after, we were going to travel the world before planting roots together in NYC finally," Thurston began in the caption of the post, which featured photos of her smiling at the beach. "But instead, my Vday was spent coordinating a place to live as I have to go back to LA for more testing and treatment. I used my morning to figure out insurance for NYC and laws on preexisting conditions. I scheduled appointments for another biopsy, fertility, mental health, surgery, as well as meeting with my team to discuss the overall treatment plan, which will include chemo."

Thurston -- who has been engaged to Jeff Arcuri since late 2024 -- continued, "I experienced a range of emotions over the past two weeks. Despair. Anger. Sadness. Denial. And then strength. Purposeful. Ready. I cried a lot. I tried to even make a video instead of this post and couldn't."

"But one thing I did early on was search other stories like mine," she added. "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."

Thurston concluded her post by sharing a message for her fiancé, writing, "I saved the best for last. To my extraordinary husband to be @jarcuri - I don’t know how I’d do this without you. The selfless love that you smother me in is beyond anything I imagined I’d be blessed with. I love you to the fullest in this lifetime and the next. 🤍."

While she mentioned in the caption that she plans on undergoing chemotherapy, Thurston also shared during the Q&A on her Instagram Stories that she will be having a mastectomy as well.

Responding to a fan who asked if she will "have chemo/and or a mastectomy first," Thurston wrote, "Yes to both. Not sure on the order yet. My fertility will be impacted by chemo so I have an appt with my fertility doctor to preserve my eggs."

Thurston appeared as a contestant in Matt James' season of The Bachelor, before she was eliminated. She subsequently led the Season 17 of The Bachelorette in 2021.

The comments section of Thurston's post in which she revealed her diagnosis became flooded with messages of love and support from many fellow members of Bachelor Nation, including Kaitlyn Bristowe, Ashley Iaconetti, and Clare Crawley.