What are the screening
tests for prostate
Digital Rectal Examination - A digital
rectal examination (DRE) is performed by a doctor during a regular office visit.
For this examination, the doctor inserts a gloved finger into the rectum and
feels the prostate gland through the rectal wall to check for bumps or abnormal
areas. Although this test has been used for many years, whether DRE is effective
in decreasing the number of deaths from prostate cancer has not been determined.
Transrectal Ultrasonography - During this
examination, high-frequency sound waves are sent out by a probe about the size
of the index finger, which is inserted into the rectum. The waves bounce off the
prostate gland and produce echoes that a computer uses to create a picture
called a sonogram. Doctors examine the sonogram for echoes that might represent
abnormal areas. Whether ultrasonography is effective in decreasing mortality
from prostate cancer has not been determined.
PSA - For this test, a blood sample is drawn and
the amount of prostate- specific antigen (PSA) present is determined in a
laboratory. PSA is a marker that, if present in higher than average amounts, may
indicate prostate cancer cells. However, PSA levels may also be higher in men
who have noncancerous prostate conditions. Scientists are studying ways to
improve the reliability of the PSA test.
Because unnecessary treatment due to false
screening results could be harmful, research is being done to determine the most
reliable method for prostate cancer screening. For example, scientists at the
National Cancer Institute are studying the value of early detection by DRE and
PSA on reducing the number of deaths caused by prostate cancer.