Thirteen-year-old Matthew Connolly didn't know what hit him when his right leg blew up like a balloon seven weeks ago.
It took three days for his calf to swell from 27 centimetres in circumference to 44 centimetres.
"He hid it from me, he didn't tell me, like most boys that age, he didn't want to tell his mum something was up and have to go to the doctors," Megan Donald said yesterday.
"The next thing we knew he was going for chemo. It was a big blow, it was scary, a huge shock."
A nasty tumour, known as Ewing's sarcoma, was behind Matthew's bulging leg.
Usually affecting adolescents, such tumours grow in bones or nearby soft tissue and often go unnoticed or misdiagnosed as growing pains or a sports injury.
For Matthew, the warning sign came quick and was hard to miss.
"If you'd seen it in the beginning, you wouldn't believe it. It just came from nowhere; his leg was normal and then it just blew up," Ms Donald said.
"The high load of chemo looks like it's working, we haven't had any results or anything, but now it's down to about 32 centimetres."
Matthew, a year 8 student at Keira High School, went to class yesterday for the first time since his diagnosis.
"He's been really strong through this," Ms Donald said. "It's been hard but I get up every day and thank God we are all breathing, we keep going."
Matthew wages his war on the tumour at the Sydney Children's Hospital in Randwick.
But for his Fairy Meadow mum - who has three other children and no driver's licence - the regular trips are taking their toll.
She relies on Illawarra volunteers to get to treatment.
"It's three days' chemo, a day of fluids then usually the next day we can go home, but that's often a Sunday when it's harder to get transport so we wait until Monday," Ms Donald said.
"We are relying on the people who give lifts, they are a huge help to us."
To make life easier for Illawarra patients, the southern region of the Cancer Council NSW is streamlining transport services.
The NSW government has put up $10,000 to make it happen.
Kiama MP Gareth Ward said research showed that 75 per cent of people interviewed by the Cancer Council's southern region office had identified affordable transport as a major barrier to getting appropriate treatment.
"The project will involve a part-time project manager working with all the community transport organisations in the Illawarra, Cancer Council NSW and the Illawarra Area Health Service to provide a best-practice model to assist passengers receiving treatment for cancer," Mr Ward said.
"By providing a range of co-ordinated options, this project will help to create a sustainable service for those who are receiving treatment for cancer and who do not have access to regular transport."

