An incurable form of leukemia was beaten off by former England cricketer John Edrich thanks to regular injections of mistletoe.
Doctors gave Edrich, 75, only seven years to live in 2000.
Five years on he was so weakened by the rare condition, Waldenstrom's macroglobulinemia, that he felt on the verge of death.
"I'm still able to play golf three times a week. Without the mistletoe I don't think I would be here," the Mirror quoted him as saying.
His GP in Ballater, Aberdeenshire, Dr Stefan Geider, and Aberdeen University cancer specialist Prof Steven Heys now plan tests to see if extracts from the "kissing plant" boost the immune system of cancer sufferers.
Dr Geider said patients in Germany had also shown huge improvements, adding, "from the results I've got, the injections give people a better quality of life."