Melissa underwent an 11-hour surgery to remove her tumour. Her body was hiding another secret

Melissa initially blamed her irritating symptoms on stress from her divorce.

The mum from Bathurst in NSW, then aged 30, was suffering from back pain and morning nausea and, as a single mother of two young children, she was programmed to ignore it.

"At 3am, I started to feel sick, I just thought I had gastro," Melissa told 9news.com.au. 

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"To be honest, I'd been in my job three months, so I didn't want my employer thinking I was having a long weekend, so I'd gone to the doctor to get a doctor's certificate."

Visiting her GP that day may have been what saved Melissa's life.

She was taken to the hospital for some blood tests after feeling light-headed, and by 2pm that afternoon, she had an unexpected diagnosis.

Melissa's pain was caused by a solid pseudo-papillary mass, a rare pancreatic tumour.

"It was the size of a large grapefruit, so it had sort of started to crush other organs, opposed to reaching out like other cancers do to the organs, so it wasn't spreading," Melissa explained.

The tumour was located at the head of her pancreas.

Her doctor said if it was sitting anywhere else, she would have had "two and a half weeks to live".

Do you have a story? Contact reporter April Glover at april.glover@nine.com.au

She needed an 11-hour surgery known as a Whipple procedure to remove the tumour.

"The doctors did say three days in ICU, 10 days in the ward, and I'd be going home," Melissa said.

"So in my naivety, I thought, within a month, I'll be back at work."

The surgery went as planned and Melissa avoided chemotherapy or radiation.

"They were pretty certain that they got it all out," she recalled.

What doctors discovered after the surgery left her "blown away".

Melissa was actually five weeks pregnant when she went under the knife.

She had no clue – nor did her surgeon.

It took months for Melissa to realise her body was growing a baby while she battled cancer.

"My ankles started to swell and then I couldn't remember when my period was, I went to the doctor and they said, 'Your body's been under too much trauma and it's normal with trauma not to get a period'," Melissa said.

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"Then I just went and got a supermarket pregnancy test."

By the time Melissa realised she was expecting her third child with her partner Braden, she was already 20 weeks along.

"It was a massive shock," she said.

Melissa gave birth to her son Jonah, who she described as a "bit of a miracle kid".

He was a healthy delivery despite the trauma his mum's body endured during pregnancy.

"He's an amazing little man," she beamed. "And I had my daughter Ava Rose after that."

Melissa was able to survive the devastating odds that a pancreatic cancer diagnosis usually brings.

One of the long-term impacts of her surgery has been a diagnosis of Type 2 Diabetes.

Over 14 years on, she grapples with some survivor's guilt.

"Because I know I'm a minority," she said.

"Whereas I've had a colleague that passed away from it two years ago.

"That's really hard to take." 

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People diagnosed with pancreatic cancer have a 13 per cent chance of surviving for five years, according to Pankind.

Melissa wants to see the pancreatic cancer survival rate boosted – something that fundraising and awareness can achieve.

"If we could get those stats up, it would become like leukaemia or a breast cancer, where it's not a death sentence," Melissa added.

"I am now trying to live life to the fullest as soon as I get that survivor's guilt happening, because I know that I shouldn't feel that way because I've got four beautiful kids and a beautiful husband and a family.

"One blessing that I took away from being sick was to refocus on what really matters."

Melissa is taking part in Remember September this year to help Pankind reach its goal of tripling the survival rate by 2030.

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