Cassandra Thorburn’s Rare Cancer Fight Leaves Fans Heartbroken

Cassandra Thorburn shares heartfelt advice after cancer-related hospitalisation

Karl Stefanovic’s ex-wife opened up about a recent hospital stint after her first dose of treatment known as “red devil” chemo.

cass thorburn and son river

Karl Stefanovic’s ex-wife Cassandra Thorburn has shared a health update amid her fight with a rare form of cancer, saying she ended up in hospital after her first dose of treatment known as “red devil chemotherapy”.

Taking to Instagram to share her latest health update, the 55-year-old and mum of three opened up about the gruelling physical toll of her treatment.

Sharing a glimpse into her daily reality, Cassandra said she ended up in hospital for five days, before candidly detailing the exhaustion that comes with chemotherapy, revealing she has been struggling with what she calls “lead legs”.

Despite the heavy physical toll, the resilient journalist and author is remarkably continuing to work full-time online from home, though she admitted that “some days are harder than others”.

Cassandra’s powerful message to friends amid cancer battle

Cassandra shared the simple, powerful ritual keeping her moving forward, encouraging others to keep it in mind if they have loved ones going through cancer treatment.

“I’m out walking this morning and hoping you will share your stories about how you kept yourself walking during chemo treatment,” she said. “Lead legs is what I call it, but it’s the weight in the bottom part of the legs that makes it really hard to go for a walk. I find it after the first 10 minutes I can keep going, it’s the first 10 minutes that are hard for me.”

“If you’re a friend of someone in chemo, please know walking is the one thing oncologists really encourage and studies show improve outcomes,” she also wrote on Instagram.

Cassandra Thorburn appears in good spirits as she is seen for the first time after announcing cancer battle | Daily Mail Online

Cassandra’s kids rally around mum

Cassandra who shares three kids with ex-husband Karl – Jackson, Willow and River – said she’s now had her second dose of treatment.

“I’ve had dose two now of my red devil friend,” Cass shared. “I didn’t enjoy staying in hospital, I’d much prefer to be at home with mum and River.”

Cassandra’s 21-year-old daughter Willow recently flew back from the UK to Australia to support her mother after her diagnosis.

A source told Woman’s Day at the time that Willow arrived back in Australia, in time to spend her 21st birthday with family.

“Cass and Willow were actually planning a driving holiday around the UK when Cass learned of her cancer diagnosis,” the insider explains. “With the help of both Karl and Cass, Willow made the decision that instead she would fly home and spend quality time with her mum.”

The insider went on to say all three of the Stefanovic children are “rallying around their mum” as she continues her cancer journey.

Willow Stefanovic flew back to Australia in March to spend some time with her mum. (Credit: Instagram)
Willow Stefanovic flew back to Australia in March to spend some time with her mum. (Credit: Instagram)

What type of cancer does Cassandra Thorburn have?

Cassandra was diagnosed with triple-negative occult breast cancer, a rare and aggressive form of the disease.

Occult means hidden, meaning this specific type of cancer had spread to the lymph nodes, but the primary tumour wasn’t detected in the breast through imaging or clinical exams. She publicly shared her diagnosis in February 2026.

Cassandra has been open about her cancer fight, often posting on Instagram about her journey and her challenges along the way, from sourcing the right information to ‘cancer ghosting’ – a phrase coined about the “nearest and dearest” friends who fail to show up when people are suffering from cancer.

In March, Cassandra shared a video stating she had a lot of positive feedback about helping others by documenting her cancer journey.

“I have had a lot of feedback that sharing my diagnosis and being open to talking about this journey is not just leading to women going for that test they have put off, it is also helping those going through chemotherapy themselves by making them feel less alone on their journey,” she shared.