Nurse mum-of-two, 35, is given just three years to live after suffering a sharp pain at the gym: 'If I didn't do that sit-up I wouldn't be alive today' 

An Australian mum has revealed how she was diagnosed with an extremely rare form of cancer after experiencing pain she dismissed as a hernia after doing a sit-up.

Jessica Slee, 35, from Adelaide was working as a nurse in Broken Hill, New South Wales in 2014, when during her regular personal training session she did a sit-up and ended up in excruciating pain. 

Eventually she went to the doctor because the 'niggling pain' wouldn't go away and was handed a diagnosis she never saw coming. 

Speaking to FEMAIL, Jessica explained her 'rollercoaster' journey which saw her become the only person in Australia with the rare cancer (Sclerosing Epithelioid Fibrosarcoma and High Grade Osteosarcoma).

'If I hadn't done that sit-up, I wouldn't be alive today,' she said.  

'I was really lucky. The doctor I saw was an experienced surgeon in the UK but was doing his hours in rural New South Wales to get accredited in Australia.

He suggested a CT scan of my abs to check for issues, but they also had to scan my chest in order to get a better picture. 

'They noticed a lump in my chest'. I also noticed the word sarcoma on the chart. I Googled it and saw it was a cancer, and an ultra rare form that was dangerous.'

Speaking to FEMAIL, Jessica explained her 'rollercoaster' journey which saw her become the only person in Australia with the rare illness and how she's balanced that with motherhood. Pictured with her husband and kids 

Soon after Jessica called her friend and former colleague in Adelaide, who told her the lump 'wasn't normal'.

'She told me 'I think you should come down to Adelaide to see a specialist'.'

After moving to Adelaide to be near her family, she had a couple of biopsies and was relieved when her results came back saying the tumour was benign.  

Despite relief that she didn't have cancer, Jessica still opted for surgery at the advice of her GP and cardiac specialist.

'As it was close to the heart, the doctors wanted it wall removed,' she said.

'I thought the cancer had been taken away, it all went well'.

But five weeks later, Jessica received a devastating call from her surgeon.

'He asked me where I was, and said that he didn't want to deliver the results over the phone,' she said.

Jessica told him she was at work but was willing to speak. 

'He explained that I had Sclerosing Epithelioid Fibrosarcoma and High Grade Osteosarcoma - a rare form of sarcoma.