Belanglo State Forest serial killer Ivan Milat is dying from oesophagus and stomach cancer and the 74-year-old could have just weeks to live, according to his nephew.
Milat was taken from Goulburn's supermax jail to the Prince of Wales Hospital in Randwick on Monday for a battery of medical tests. He's now been diagnosed with terminal cancer.
Milat's nephew, Alistair Shipsey, says his uncle's condition is "very bad".
"I've been informed he's only got a couple of weeks to live," Mr Shipsey told Ten News on Thursday.
Milat - who's reportedly lost 20 kilograms in recent weeks - hasn't been able to eat or keep food down.
"So to me they've known for months - why didn't they treat it?" his nephew said, adding he wanted to visit his uncle - whom he believes is innocent - "before he dies".
"He's one of my favourite uncles," Mr Shipsey said.
Milat is being held in a secure annexe of the Randwick hospital and is expected to stay there for a number of days.
AAP understands he won't be returned to Goulburn. It's been reported he could go to Long Bay Hospital inside the jail at Malabar.
The former road worker was sentenced in 1996 to seven consecutive life sentences for murdering seven backpackers whose bodies were found in makeshift graves in NSW's Belanglo State Forest in the 1990s.
He also kidnapped British tourist Paul Onions who managed to escape from Milat's vehicle.
NSW Corrective Services NSW Commissioner Peter Severin earlier this week said prisoner transfers were done in the "most secure and safe way possible".
High-risk and terrorism-related inmates are always guarded by specialist staff from the extreme high-security escort unit, a corrective services spokeswoman said.
At least one form of restraint - handcuffs or ankle cuffs - stay on high-risk inmates during medical treatment subject to medical requirements.
Australian Associated Press