The Today Tonight host knew something was wrong. She ate well, exercised and had always been healthy. Now, it was as if her body "just didn't feel comfortable in its own skin". Determined to get to the truth, she pushed for more tests. None gave an answer; they simply eliminated possible causes.

At this point, her best friend took her aside. Having had ovarian cancer, she was concerned that Kapalos's symptoms were a sign of something similar. A scan was quickly arranged. "I was lying there, watching it all on the screen," Kapalos, 42, says. "They identified it straight away and said, 'Wow. This is a really large tumour.' The first thing I thought is that this is Mum's story. But this time, I want it to have a different ending."

Until now, Kapalos has not spoken in detail about her experience. A private person, she was motivated to go public partly to encourage awareness of ovarian cancer, but also because of the death of her mother, Joanna, from cancer. Joanna's symptoms were also initially dismissed by doctors, and she did not get the life-saving surgery she needed.

"I've decided to talk about this because I don't want to see people going through what Mum went through," she says. "But this is not about being alarmist, nor am I a 'victim'. This is about women being proactive and positive about their health."

The story begins almost 20 years ago in the NSW coastal town of Newcastle, when Kapalos – then a 22-year-old reporter at ABC Radio – was still living in the family home. She remembers every detail of that night. It was hot, the airconditioner humming in the background, and she had fallen asleep on the couch, still wearing her sandshoes. In the early hours, she was woken by her mother. "She just walked out and had a massive haemorrhage," Kapalos says softly. "The paramedics told us she was only 20 minutes from death."

An ambulance rushed her to hospital, where she received a radical hysterectomy and multiple blood transfusions. A few days later, doctors broke the devastating news: the benign fibroid on her uterus had morphed into malignant, inoperable cancer. If it had been removed even a few months earlier, they told her, she'd most likely have recovered.

Joanna died 15 months later, aged 56. "I was the one taking mum to the doctor when she had her fibroids," Kapalos says. "I was really concerned they were growing so quickly. But the doctor just said to her, 'It's benign, we'll leave it. Surgery's too invasive.'"

We're sitting in the living room of Kapalos's inner-Melbourne warehouse apartment; a former wool factory with exposed brick walls and heavy wooden beams. Her shelves are crammed with stacks of Vanity Fair magazines and books by Joan Didion and David Sedaris. A huge pinboard is festooned with black-and-white family photos.

"Check this out," she says, bounding upstairs. Bolted to the wall is a 400-year-old green door from India, which serves as a bedhead. "I like sleeping with something solid behind me." Next to her bed is a hand-painted sign: "Fall down seven times, get up eight." It's the same message she tweeted on the night last year she was sacked by Channel Ten in a cost-cutting drive. It also typifies her resilience in the face of her recent health problems.

"When I was diagnosed, I thought, 'There are two columns I can put this into: reactive or proactive," she says firmly. "Immediately, I went, 'Of course this is confronting. But now that I finally know what it is, I'll find out everything I can about it, how to deal with it and how to heal from it."

The toughest period was the few weeks between finding the tumour and having it removed. Until they operated, the surgeons couldn't tell if it was malignant, or whether they'd need to take out other organs. "The hardest part was ringing Dad," she says. After her mother died, her heartbroken father, Dimitri, returned to Greece, where Kapalos visits him every year. "He was in shock. But I said to him, really emphatically, 'It will be a different outcome this time.'"

In August, she went under the knife. Surgeons removed a tumour slightly bigger than a tennis ball from her right ovary. It was benign, and that's all they took out. Six weeks later, she was given a clean bill of health. "It's the best possible outcome," she says, smiling.

She is under no illusions, though, about what might have happened had she "stopped worrying", like her first doctor advised. At best, her tumour would have grown rapidly, requiring a major operation instead of keyhole surgery. At worst, it could have turned fatally malignant – just like her mother's. "I felt Mum's presence acutely at this time," she says. "I think I've always had this story playing out in my subconscious."

Her refusal to let doctors dismiss her early symptoms is no surprise. Yet even after her tumour was discovered, she kept a level head. Her first specialist, for instance, blithely ordered the removal of her ovary. When Kapalos questioned her, she was affronted. "I received a schoolgirl chiding," she says. "Luckily, I sought another opinion and the next specialist said, 'No, we don't need to take out your ovary at all.'" This means her fertility has not been affected. "My message to other women is, 'Don't let one doctor encase your diagnosis in alarmist terms. Get that second opinion. Explore the other options. There are always other options.'"

Kapalos stresses she is not criticising all doctors. In her experience, most are thorough, empathic and professional. Nor does she want people to self-diagnose via Google or start thinking they know more than their specialists. But she does suspect some women are reluctant to "make waves" by questioning their doctor or seeking alternatives. "We need to be vigilant about our health," she says. "We need to be okay with checking in on ourselves and following through on that."

Her commitment to preventative health is why she cycles to Channel Seven's Melbourne studios most days, favours wholesome Japanese and Greek foods and devours books about philosophy and self-improvement. It's also why she serves as an ambassador for the Ovarian Cancer Research Foundation. "Ovarian cancer mortality rates are higher than those for other cancers," she explains, pointing out that the symptoms frequently mimic those of other conditions. "It's often not detected until the late stages. There's so much more awareness about breast cancer now, thanks to all those fantastic campaigns. We need that same type of awareness with ovarian health."

In fact, Kapalos has been a foundation ambassador for eight years, well before her tumour was discovered. She has also been a board member of Melbourne's Federation Square, is the number-one female ticket holder of Hawthorn AFL club, and an avid pianist, guitarist, blogger and yoga devotee. No wonder friends call her "Hurricane Helen". But even she admits that, recently, something had to give. Barely 48 hours after being wheeled into surgery, she was back in front of the camera. Medicated and in pain, she accidentally referred to Melissa Doyle as "Melanie" during a live cross to London.

"I got an abusive phone call from my doctor as soon as the show finished," she says, laughing. "He'd ordered me to take a fortnight to recover, but I honestly thought I could do it. I had no comprehension of the pain I'd be in. Since then, 'Hurricane Helen' has been downgraded, which is a good thing."

One thing she'll never downgrade is time with her five nieces: Amy, Sophie, Chloe, Nikki and Grace. Kapalos returns to Newcastle every month to see them and they often stay with her in Melbourne. "They're the five bright, shining lights of my life," she says. "But I also take my role as an aunty very seriously, because they've never had a grandmother on my side. I want to help empower them. I want to show them that life will always have its ups and downs but how we respond is up to us."

Recently, one of her nieces split with her boyfriend, and she confided in Kapalos. "She said, 'I only ever knew you when you were married. Now I've seen you thrive as a single woman, too.' She was encouraged by that."

Kapalos was 18 when she met physiotherapist Craig Boettcher. They were together for 18 years before divorcing in 2007. "I married the first man I fell in love with and that was a rewarding experience. But I've since been happy on my own, too. This year has been about getting my house and health in order. I'm open to a relationship, though. I love the idea of being in love and having a fulfilling partnership."

Naturally, she'd be delighted for her five nieces to find the same. If there's one piece of advice she can give them, however, it's this: your relationship does not define you. "I always tell my nieces, 'You are already a complete individual! Learn to see yourself through your eyes first, not somebody else's.'"

Professionally, she's never been more satisfied. In the course of her two-decade career she's worked in radio and TV – as a producer and presenter – for ABC, SBS and every commercial network. A highlight is The Last Whistle, a 1998 documentary she wrote, directed and produced at regional TV station NBN about the closure of Newcastle's BHP steelworks. "Journalism is the most rewarding profession you'll ever be fortunate enough to be in," she says. "I'm confounded when I hear young women say, 'I want to be a presenter on prime-time TV.' Is that about being a journalist or having a profile?"

Naturally, she is heavily involved in the planning of every Today Tonight episode. Her workday begins at 7.30am, when she dials in to a conference call from home. By noon, she is in the office, attending meetings, recording radio promotions and watching early cuts of each story. "I loved my time at Channel Ten," she says, "but I can only look back on it as being successfully fired from a job I had probably outgrown. I've never worked in an environment where it's so hands-on and rewarding as where I am now.

"Everything that's happened this year has made me even more positive. There's so much more I want to do in this world. I see it as a green light to just get out there and keep embracing life."

OVARIAN CANCER: FACTS, SYMPTOMS AND ADVICE

• Ovarian cancer has the lowest survival rate of any gynaecological cancer and there is currently no early detection test.

• In Australia, the five-year survival rate for women diagnosed with breast cancer is 89 per cent; for ovarian cancer, it is 43 per cent.

• The four most frequently reported symptoms for ovarian cancer are: abdominal or pelvic pain; increased abdominal size or persistent abdominal bloating; needing to urinate often or urgently; feeling full after eating a small amount.

• If these symptoms are new and you experience one or more of them persistently over four weeks, consult your GP.

• You can also download Ovarian Cancer Australia's symptom diary at ovariancancer.net.au, or the KISS & Makeup iPhone app, which allows you to record your symptoms and helps you communicate with your GP.

Source: Ovarian Cancer Australia.

Styling by Penny McCarthy; hair by Richard Kavanagh; make-up by Naomi McFadden. Lead-in image: Helen wears shirt by Peter Pilotto from Net-a-Porter. Above image: Helen wears dress by Max Mara.