Katie Thurston Confirms Her Cancer Is Stage 4 but She's 'Optimistic' and Will Start Treatment Next Week

Katie Thurston is speaking candidly about her stage four breast cancer diagnosis.

Four days after announcing that her stage 3 breast cancer (invasive ductal carcinoma) diagnosis might have progressed to stage 4 after signs of the disease were discovered on her liver, Thurston, 34, confirmed the news in a video on Instagram.

"After days of waiting, unfortunately, I did find out today that my breast cancer has spread to the liver. It is fairly small, however, that does put me at stage four," Thurston, who announced her initial diagnosis in February, said.

Thurston had been awaiting the results of a liver biopsy after she underwent a PET (Positron Emission Tomography) scan that ended up detecting "some spots on my liver that were a little suspicious."

According to the Cleveland Clinic, a PET scan detects "early signs of cancer, heart disease and brain conditions," by using "an injection of a safe radioactive tracer that helps detect diseased cells."

The former Bachelor star said while she had many tests done before her move to New York from Los Angeles, PET was a test she had not undergone.

"I decided to focus on fertility before doing treatment," she noted.

Sharing that it had been 43 days since she was originally diagnosed with breast cancer and had not undergone treatment, Thurston said she is on a “new treatment plan” that is going to start next Friday, which "does involve chemo."

“I know stage four can sound very scary, and it can be," said Thurston. "However, 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. I'm very confident in the team at Columbia and I just wanted to share that update."

The former reality star also shared her story in the post's caption.

"43 days since diagnosis and still no treatment? There is a lot of testing and prep that goes into cancer treatment. One important test is checking to see if the cancer has metastasized (spread). Unfortunately for me, mine has and I am now #stage4breastcancer . I’ll finally start my treatment next week. 💕 #breastcancersupport #breastcancer," she wrote.

Over on her Instagram Stories, Thurston answered questions from her followers during which she explained that her "treatment is spaced out as six treatments to start, three weeks apart."

"A treatment is essentially a dedicated day to travel/infusions/recovery," she added. She also shared that the treatment plan for her liver is "essentially the same" as the one for her breasts, as "the cancer that is within the liver is from the breast cancer spreading vs a new type of cancer."

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On Monday, March 4, Thurston shared on her “Boobie Broadcast” channel on Instagram that the "two liver lesions" were discovered, measuring up to 1.4 cm, were likely a sign of “metastatic disease."