US toddler diagnosed with rare ovarian cancer now cancer-free

One toddler is celebrating big news after four months of chemotherapy.

And if the big smile on her face doesn't give it away, the T-shirt does — with the two-year-old posing in a top with the phrase "This unicorn beat cancer" emblazoned across it.

McKenna 'Kenni' Shea Xydias was diagnosed with a rare form of ovarian cancer in February.

Now, following four rounds of chemo in just as many months, the little girl from Georgia has gotten the all clear.

Parents Mike and Meagan Xydias helped their daughter ring the hospital bell to signify the end of her treatment.

The couple have kept family, friends and followers in the loop through the Facebook page Fight With Kenni and they shared their thanks for everyone's support across the process.

"We can’t say 'Thank you' enough to everyone for all of the love, support, and prayers that our sweet Kenni and family have received over the last four months," they wrote.

"Dr. Sutton came in — she just got straight to it and said, 'Scans were clear. There's nothing there,'" Kenni's mum, Meagan, told Good Morning America of the big moment.

"We sat and cried and held each other for a minute," she added.

On February 15 following weeks of an on-off fever, the Meagan took Kenni to the doctors for what they thought was just some gas.

But the diagnosis turned out to be much more serious, with scans finding an ovarian yolk sac tumour — considered a stage three malignant cancer at the time.

The tiny tot underwent surgery to remove her right ovary and along with five inches (or 12cm) of her small intestines.

Then came the gruelling chemotherapy but father-of-three, Mike, says his daughter has grown from the experience.

"[Kenni] was shy and reserved before all this. With all the poking and prodding and meeting new people, she's really come out of her shell," he tells GMA of the silver lining.

Ovarian yolk sac tumour is a rare, malignant growth of cells that form over the yolk sac of a woman’s embryo.

The cause is unknown, and the condition is most often found in children before the age of two.

The condition accounts for less than five per cent of all ovarian cancers, making it incredibly rare, and treatment is often dependent on where the tumour is located and how advanced in its progression it is.

If the tumour is in the ovaries, patients will undergo chemotherapy and surgery.