Men with early prostate cancer who choose to closely monitor their disease are just as likely to survive at least 10 years as those who have surgery or radiation, a UK major study has found.
Survival from prostate cancer was so high - 99 per cent, regardless of which approach men had - that the results call into question not only what treatment is best but also whether any treatment at all is needed for early-stage cases.
And that in turn adds to concern about screening with PSA blood tests, because screening is worthwhile only if finding cancer earlier saves lives.
"There's been no hard evidence that treating early disease makes a difference," said Dr Freddie Hamdy of the University of Oxford, the study's leader.
"Because we cannot determine very well which is aggressive cancer and which is not, men and clinicians can both be anxious about whether the disease will progress," he said. "And that pushes them toward treatment."
Dr Otis Brawley, chief medical officer for the American Cancer Society, welcomed the results but said it would be a struggle to convince men diagnosed with early prostate cancer in the US to skip surgery or radiation.
He said he often suggests monitoring but "it's a challenging process to explain to people that certain cancers just don't need to be treated."
"Our aggressive approach to screening and treating has resulted in more than 1 million American men getting needless treatment," said Brawley, who had no role in the study.
The research was published online on Wednesday in the New England Journal of Medicine.
It was paid for by Britain's National Institute for Health Research.
