The family of a four-year-old Melbourne girl says her medical bills could soon exceed half a million dollars as she bravely battles her third type of cancer in three years.

Uma Tomarchio was born in Australia and has spent her whole life here but does not qualify for Medicare – which would normally cover the cost of her cancer treatments – because her parents are Italian.

Uma's parents moved to Australia seven years ago and the family of four, including Uma's older sister, has been living here on temporary skilled work visas ever since.

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Uma's health problems began in 2020, when she was diagnosed with acute lymphoblastic leukaemia at two years old.

Eighteen months later, Uma appeared to be in the clear after initially responding well to chemotherapy. 

However, just as she was due to finish all of her treatment in October 2022, Uma relapsed. 

The cancer came back in a more aggressive form – acute myeloid leukaemia. 

The cost of Uma's treatments had, until then, been covered under the family's health insurance, however, the bone marrow transplant she needed was not.

Beating seemingly insurmountable odds, Uma's family managed to fundraise the $300,000 cost of the transplant, which took place at the Royal Children's Hospital in September last year.

Uma's father, Giuseppe Tomarchio, told 9news.com.au the bone marrow transplant appeared to have been a huge success – at first.

"The transplant went great," Tomarchio said.

"Uma didn't have any complications during the transplant. She was doing really well. She never stopped walking and playing during transplant.

"It was really impressive."

After spending 45 days in hospital, Uma was discharged earlier than expected.

But, one month later, Uma suddenly developed a fever.

Concerned, her parents took her back to hospital, where her condition deteriorated rapidly as doctors tried to figure out what was wrong.

The news, when it came, was devastating.

Just before Christmas last year, Uma was diagnosed with lymphoma – a cancer of the lymphatic system. The lymphoma was likely caused by a rare complication related to the bone marrow transplant.

"It was devastating, we couldn't believe it. It was like come on, this is not fair," Tomarchio said.

All up, Uma spent 40 days in the hospital's intensive care unit (ICU) – some of them in an induced coma – with failing kidneys and a ventilator allowing her to breathe.

"She was critical, the doctors were really unsure whether she would make it," Tomarchio said.

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Uma underwent more chemotherapy to slow down the growth of the tumours in her lymph nodes.

Then, three weeks ago, Uma was given an infusion of donor white blood cells from Queensland.

Defying her weakened state, Uma responded amazingly well to the treatment and was now out of the ICU, Tomarchio said.

"She actually walked a bit for the first time the other day. It was a big day and a big celebration," he said.

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