Napier resident Jarred Thompson was admitted to a Fijian hospital on Thursday while on holiday with a friend.
His friend Thomas Brook said what started as a headache turned into a potentially life-threatening condition.
A medical evacuation team has been organised to get him home as he required more tests in New Zealand.
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Thompson has travel insurance, but it did not provide cover for medical evacuation, Brook said.
Friends and family hope to raise the $27,000 to pay for medical staff to escort him home to New Zealand.
“He can hear me, but cannot respond. It must be torture. He constantly kicks and taps to let us know he’s still here,” Brook wrote on the Givealittle fundraising page.
“The longer he sits here the worse it gets,” Brook said, adding that it can be life-threatening.
The trip to Fiji was planned a year ago, just before Thompson was diagnosed with testicular cancer. The cancer then spread to Thompson’s lungs and liver.
With news of the diagnosis, the trip was put off and they “embarked on a completely different journey” to fight cancer, Brook said.
After a year of tough cancer treatment and “battling life between the ICU and CCU”, the duo decided to carry on with their original plan.
Part of the planned one-month holiday was attending a wellness camp, which Thompson had hoped would improve his health.
The “strong dude” suffered from a headache and felt unwell a few days after the camp, Brook said.
Thompson ended up vomiting and lost his speech before he was taken to the hospital last week.
“I was really scared. The hope was in getting him home,” Brook said.
Doctors at the Fijian hospital said they would only treat him with palliative care and suggested Thompson be brought back home for treatment, he said.
“We’re on a time sensitive case here. They [the doctors] said they need him to come back to New Zealand, so they can do comprehensive testings,” Brook said.
The Givealittle page, which was pending approval, had raised more than $13,000 by Sunday morning.