Prostate Cancer Survival Rates Improved After Introduction of PSA Screening
Growing evidence that questions U.S. Preventative Services Task Force recommendation against PSA screening in all men
Aug. 23, 2012 – The latest round in the on-going debate over the routine use of prostate specific antigen (PSA) to screen
for and monitor prostate cancer is a new study that compares studies before and after the “PSA era.” The lead investigator concludes that
‘without a doubt it has played a role in extending many lives.”
The routine use of prostate specific antigen (PSA) testing for screening and monitoring prostate cancer has led to early
and more sensitive detection of the disease, according to the study published in The Journal of Urology.
The report shows survival has improved for patients with newly diagnosed prostate cancer that has spread to the bones or
other parts of the body and the disparity between African American and Caucasian men has been resolved.
Data very clear: not doing PSA will result in many men with far more advanced prostate cancer spread to other parts of the
July 30, 2012 - Eliminating the PSA test to screen for prostate cancer would be taking a big step backwards and would
likely result in rising numbers of men with metastatic cancer at the time of diagnosis, predicted a University of Rochester Medical Center
analysis published in the journal, Cancer. Read more...
"Our analysis indicates an overall improvement in risk adjusted survival rates for non-African American and African
American men. Of note is the resolution of disparity in survival between the races found in earlier studies," says lead investigator Ian M.
Thompson, Jr., MD, Director of the Cancer Therapy and Research Center, a National Cancer Institute-Designated Cancer Center, and Professor in
the Department of Urology at the UT Health Science Center at San Antonio, TX.
The Southwest Oncology Group, a National Cancer Institute (NCI) sponsored organization that conducts clinical trials in
adult cancers, has performed a series of clinical trials over the last three decades that evaluated patient survival after androgen
deprivation treatment (ADT) for prostate cancer.
Two of the trials took place before, and one took place after the introduction of PSA screening.
Recommendation to End Regular PSA Screening
In 2011, the U.S. Preventative Services Task Force recommended against PSA screening in all men, prompting criticism from
the medical community. The government panel reviewed scientific evidence and concluded that screening has little or no benefit, or that the
harms of early detection outweigh the benefits.
One major concern, for example, was that doctors are screening for, finding, and treating non-aggressive cancers that
might have remained quiet, causing patients to needlessly suffer from serious treatment side effects such as incontinence or erectile
The U.S. Task Force recommendations against screening caused some confusion, and in response, a special panel of experts
from the American Society of Clinical Oncology this month issued its own opinion.
The ASCO panel decided that for men with a life expectancy of less than 10 years, general screening with the PSA test
should be discouraged. For men with a longer life expectancy, though, it is recommended that physicians discuss with patients whether the PSA
test is appropriate for them.
"These sequential trials provide an opportunity to address the question of whether survival has improved since the advent
of widespread PSA screening and follow-up testing," says Dr. Thompson.
Patient populations and eligibility criteria were comparable across the three studies, which enrolled patients from
cancer centers around the country. Patients in all three trials received similar ADT treatments.
Median survival in trial S8494, which enrolled patients from 1985 to 1986, was 30 months, and median survival in trial
S8894, which enrolled patients from 1989 to 1994, was 33 months. In contrast, median survival in trial S9346, which enrolled patients from
1995 to 2009, was 49 months. A 30% decreased risk of death was found in the most recent trial (S9346) from the previous trial (S8894).
The interaction of various risk factors, such as extensive versus minimal disease, older age, race, and body mass index
was assessed. In S8494 the median survival for African American men was 27 months, while in S9346, the survival rate was 48 months, which is
very close to that of white men.
Dr. Thompson notes that African American men had poorer results in the earlier studies despite receiving treatment in a
carefully overseen clinical trial.
"When we evaluated ZIP code summary information regarding income and education, there was no shift in socioeconomic
status over time. We hypothesize that this improvement is based on greater awareness of prostate cancer and improved health seeking behavior
in African American men."
However, African American men have a two- to three-fold greater incidence of newly diagnosed metastatic prostate cancer
compared to white men, which contributes to a similarly increased mortality rate.
"A greater effort is needed to eliminate disparities in prostate cancer," he says.
Dr. Thompson concludes, "While not all of these welcome improvements can be attributed strictly to PSA testing, without a
doubt it has played a role in extending many lives."
Cancer Statistics 2011 shows among men the
reduction in lung, prostate, and colorectal cancers is nearly 80% of
decline; among women, almost 60% of decrease in breast and colorectal -
see chances of seniors getting cancer - June 17, 2011