Innocente Marcolini, 60, an Italian businessman, fell ill after using a handset at work for up to six hours every day for 12 years.
Now Italy’s Supreme Court in Rome has blamed his phone saying there is a “causal link” between his illness and phone use, the Sun has reported.
Mr Marcolini said: “This is significant for very many people.
I wanted this problem to become public because many people still do not know the risks. “I was on the phone, usually the mobile, for at least five or six hours every day at work.
“I wanted it recognised that there was a link between my illness and the use of mobile and cordless phones.
“Parents need to know their children are at risk of this illness.”
British scientists have claimed there is insufficient evidence to prove any link to mobiles.
But the respected oncologist and professor of environmental mutagenesis Angelo Gino Levis gave evidence for Mr Marcolini — along with neurosurgeon Dr Giuseppe Grasso.
They said electromagnetic radiation emitted by mobile and cordless phones can damage cells, making tumours more likely.
Prof Levis told The Sun: “The court decision is extremely important. It finally officially recognises the link.
“It’ll open not a road but a motorway to legal actions by victims. We’re considering a class action.”
Mr Marcolini’s tumour was discovered in the trigeminal nerve — close to where the phone touched his head.
It is non-cancerous but threatened to kill him as it spread to the carotid artery, the major vessel carrying blood to his brain.
His face was left paralysed and he takes daily morphine for pain.
Alasdair Philips of Powerwatch, which campaigns for more research on mobile use, said: “This is an interesting case and proves the need for more studies.
“People should limit mobile and cordless use until we know more.”
The World Health Organisation urged limits on mobile use last year, calling them a Class B carcinogen.
But a spokesman for Britain’s Health Protection Agency said: “The scientific consensus is that mobile phones do not cause cancer.”
International radiation biology expert Michael Repacholi said: “Studies show no evidence of cancer. But if you are worried, use a headset, hands-free or loudspeaker.”
Media lawyer Mark Stephens said the verdict could “open the floodgates” — even though there is no direct obligation on British courts to follow the Italians’ lead.
He said: “It is possible people will begin legal action here, but I think the chances of success are less. I think they’ll join any class action in Italy.”