Something looked off about 16-year-old Chelsea's neck. A few weeks later, she was diagnosed with ovarian cancer

At first glance, the photo of Chelsea Regan looked totally innocent.

Then her mum noticed her neck looked a little unusual and a few weeks later, the 16-year-old had an ovarian cancer diagnosis.

"We went to see an endocrinologist about my thyroid," Regan tells 9honey, but there was nothing wrong with her neck or thyroid at all.

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Instead, the endocrinologist was concerned about her other mystery symptoms: severe acne, excessive body hair, and an uncommonly deep voice.

Regan also hadn't had a period in two years but her cycle had always been irregular, so she "played it off as puberty".

All the symptoms she'd been ignoring turned out to be crimson red flags for a Sertoli-Leydig Cell Tumour, a rare and potentially deadly subtype of ovarian cancer.

Commonly misunderstood as an 'older woman's' disease, about two in five of the estimated 1800 Australians diagnosed with ovarian cancer every year are women under the age of 60.

Teenage cases are considered rare but an increase in awareness in recent years has seen more young women diagnosed, as they now know what vague symptoms to look out for.

Even so, being diagnosed with the most lethal gynaecological cancer at 16 was a uniquely terrifying and isolating experience for Regan.

Within a few weeks of her diagnosis she underwent surgery to have her left ovary and the tumour growing on it removed. She hoped – perhaps naively – that would be the end of it.

"They got it out pretty quickly, which made me think that everything was all good," she says.

But average five-year survival rate for ovarian cancer patients is just 49 per cent, due in part to the fact that about 70 per cent of patients experience a recurrence.

Regan was just 18 when hers came back.

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Thrown back into the harrowing world of ovarian cancer treatment, she had to grapple with cancer treatment and decisions about her fertility when she was supposed to be enjoying her last year of school before transitioning into adulthood.

"There were questions like, 'Will I be able to have kids with just one ovary? How will I function as a woman?'" she recalls.

It was a confronting and lonely time for Regan, who spent endless hours in hospital waiting rooms and fertility clinics populated by women decades older than her.

The worst part of it all was knowing that every year, another 1800 women and girls just like her receive the same diagnosis that turned her life upside down.

One of the greatest challenges in the fight to reduce ovarian cancer death rates is the fact that there's still no early detection test for this silent killer.

And with more than 30 known subtypes of ovarian cancer, it's not a simple case of developing one early detection test to catch them all.

"I anticipate there's not actually going to be one early detection test. There's going to have to be multiple diagnostic tests, because ovarian cancer is such a complex disease," OCRF Research Advisor Dr. Amy Wilson said.

"But there's some really, really exciting research coming out at the moment."

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Researchers around the world – including some here in Australia – have made significant progress towards developing an early detection tests in recent years, with some even entering clinical trials.

About a quarter of ovarian cancers are linked to an inherited genetic mutation or family history, making genetic testing another important avenue for prevention and treatment.

Those family links are also why it's so important to end the stigma around women's health, as the best way to inform the next generation about their own risk is by having more conversations.

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"One of the barriers to driving greater awareness and engagement around a cancer like ovarian cancer is how awkward we find talking about reproductive health," she says.

"But some of those conversations genuinely can change the course of someone's life."

For example, Regan's cancer was found to be linked to a gene mutation, which she can inform any future children so they know their own risk.

It also meant she required tailored treatment for her specific case, but ovarian cancer treatment options have barely improved in the last 30 years.

OCRF Donor and Partnerships Director Georgie Herbert's mother was diagnosed with ovarian cancer in 2006, and little has changed since her diagnosis almost three decades ago.

"Stats were so grim when my mum was diagnosed and they haven't really shifted all that much in the time since," Herbert tells 9honey.

Despite being given just a few years to live, Herbert's mum survived for 11 and inspired her to take action.

Desperate to see a future with better treatments, improved survival rates, an early detection test and – hopefully one day – a cure, Herbert's been working with the OCRF ever since to raise funds and awareness.

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Now 20 and cancer-free, Regan has also joined the cause as an OCRF ambassador using her story to educate Australians on the fact that ovarian cancer is not and never has been just an 'older woman's' disease.

She ran every day in February – Ovarian Cancer Awareness Month – to get the word out about how "terrifying" it is to be diagnosed with a cancer that is so underfunded.

"The best we can do is try to make other people aware and raise the funds for an early detection test, so that other women don't have to suffer and instead have a fighting chance of this disease," she says.

"Too many women find out way too late."

About 70 per cent of ovarian cancer cases are diagnosed in the later stages, when it's already spread, and an estimated 10,000 Australian women and girls will lose their lives to this disease in the next 10 years unless something changes.

Women's healthcare has been historically underfunded, especially reproductive health, and the stats around diseases like ovarian cancer won't shift without long-term funding for potentially life-saving research.

"When we say nothing much has changed in the last handful of decades it's not because there's not great things happening, it's just that research is a long game," Herbert says.

The OCRF works tirelessly to fund vital research into better treatment, early detection, and a cure – but a significant portion of that funding depends on the generosity of everyday Australians.

"I know not everyone has the means [to donate], but if they can get involved in fundraising for ovarian cancer research that would be awesome," Wilson adds.

Today, February 28, marks the final day of Ovarian Cancer Awareness Month. To learn more and donate, visit the OCRF website here.

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