Metastatic disease emerges as endpoint in PSA debate
Previous researchers have used mortality as an endpoint in analyses of PSA screening and focused on the negative effects of stage migration due to earlier detection. However, Jay P. Czieki, MD, from the department of radiation oncology at Cleveland Clinic, and colleagues, wrote. “The metastatic disease burden of the population is extremely important in prostate cancer patients because of its long natural history and quality-of-life decrements associated with its treatment (endocrine therapy, chemotherapy, palliative radiotherapy, narcotic analgesic use and hospitalizations).”
Czieki and colleagues devised a study to determine the impact of PSA screening on metastatic disease burden. They analyzed medical records of 1,721 patients treated for prostate cancer from 1986 to 1996 and divided the patients into two cohorts: PRE, a pre-screening era group from 1986-1992, and POST, a post-screening era group from 1993 to 1996.
The researchers adjusted for lead-time bias by comparing the 10-year metastasis-free survival rate of the PRE group to the 15-year rate of the POST group.
Among the 575 men in the PRE group the metastasis-free survival rate was 58 percent for high-risk men, 79 percent for intermediate-risk men and 90 percent for low-risk men.
Comparative metastasis-free survival rates among the 1,146 men in the POST group were higher in each risk category at 65 percent, 86 percent and 96 percent for high-, intermediate- and low-risk, respectively.
“The importance of metastatic disease burden on a patient population is significant for many reasons, including quality-of-life and financial cost, and it needs to be considered when determining the value of PSA screening,” Czieki et al concluded. The effect of screening on metastatic disease should be considered as physicians weigh the role of screening, they continued.