Fmr. US President begins radiation treatments for tumours

US ex-president Jimmy Carter said on Thursday that he is beginning treatments for cancer immediately.

The 90-year-old, who was president from 1977 to 1981, said that doctors had found a tumour on his liver that proved to be melanoma, which is typically a skin cancer.

Suspecting the cancer on his liver had spread from elsewhere, doctors eventually found four very small melanomas on his brain, which Carter said were measured in millimetres.

"I get my first radiation treatment for the mel in my brain this afternoon," he said at a news conference at his Atlanta-based Carter Centre, a non-profit organization promoting peace and democracy.