Untreated prostate cancer can turn to lethal disease over long-term

New findings from a long-term study of men with early-stage, initially untreated prostate cancer suggests that the risk of progression to more aggressive and lethal disease increases significantly in the long-term, according to a study published in the June 9 issue of The Journal of the American Medical Association (JAMA).

According to background information in the article, without understanding the natural history of prostate cancer diagnosed at an early, localized stage, patient counseling and clinical management are difficult. The challenge is to maximize the possibilities for survival without extensive overtreatment. Even without initial treatment, only a small proportion of all patients with cancer diagnosed at an early clinical stage die from prostate cancer within 10 to 15 years following diagnosis. However, little is known about disease progression and risk of death beyond 10 to 15 years of watchful waiting.

Jan-Erik Johansson, M.D., Ph.D., of Örebro University Hospital, Örebro, Sweden, and colleagues analyzed survival following "watchful waiting" in 223 patients from central Sweden with early-stage, initially untreated prostate cancer. There was a mean observation period of 21 years.

The researchers found that after complete follow-up, 39 (17 percent) of all patients experienced generalized disease. "Most cancers had an indolent [slow to develop] course during the first 10 to 15 years," the authors write. "However, further follow-up from 15 (when 49 patients were still alive) to 20 years revealed a substantial decrease in cumulative progression-free survival (from 45.0 percent to 36.0 percent), survival without metastases (from 76.9 percent to 51.2 percent) and prostate cancer–specific survival (from 78.7 percent to 54.4 percent). The prostate cancer mortality rate increased from 15 per 1000 person-years during the first 15 years to 44 per 1000 person-years beyond 15 years of follow-up."

"Our data may be important for counseling and clinical management of individual patients. Postponement of death is not the only treatment objective because local progression may create substantial suffering," the researchers write. "In conclusion, our data indicate that the probability of progression to a more aggressive and lethal phenotype may increase after long-term follow-up of prostate cancers that are diagnosed at an early stage and initially left without treatment. These findings argue for early radical treatment of patients with long life expectancy."