As of now, there's no way to tell early on which cancers are which, so tens of thousands of men undergo surgery or radiation each year for cancers that never needed treatment , risking impotence or incontinence in the process.
Several recent genetic discoveries could help doctors evaluate how aggressive a man's prostate cancer is much earlier. Scientists at the University of Michigan have identified at least 24 different kinds of prostate cancer of varying virulence whose DNA signatures can be read like a bar code. Memorial Sloan-Kettering Cancer Center researchers have identified other genetic subtypes of prostate cancer that seem to predict whether the tumor will be low or high risk. And Harvard Medical School scientists have found a specific gene that causes prostate cancers to spread. Some of the discoveries also could lead to new treatments, tailored specifically for the kind of prostate tumor a man has.
Such genetic tests for prostate cancers would go well beyond the current PSA test (for prostate-specific antigen) used for screening men in general. PSA tests have helped find prostate cancers at much earlier stages, saving thousands of lives in recent years. But PSA levels also rise for reasons that have nothing to do with cancer, prompting many men to have prostate biopsies each year that don't find cancer or that find tumors of the slow-growing variety.
Scientists say new prostate-cancer tests could be available in the not-too-distant future. "It won't be tomorrow, but if you go by the pace at which such technology entered the field of breast cancer , it will be several years [for new prostate tests], not a decade," says Charles Sawyers, chairman of human oncology and pathogenesis at Memorial Sloan-Kettering.
Source: Health Journal, The Wall Street Journal, June 29, 2010