Nobody knows whether prostate screening saves lives

Cancer screening means testing for signs of cancer **before there are any
symptoms**, on the reasoning that by the time a cancer causes symptoms it may
already have spread. A screening test does not diagnose anything; it tells you
whether you might have cancer, and a positive result sends you for further
tests.

Prostate cancer screening looks for signs of cancer in the prostate, a gland
below the bladder that makes fluid for semen. It is most common over 50,
**usually grows slowly, and often causes no health problems at all — it is
possible to live a long life with prostate cancer and never know.** Sometimes
it spreads and becomes very serious. The goal of screening is to find the
second kind early.

The two tests, and what they cannot tell you

PSA blood test. PSA is a protein made by the prostate. A high level may
mean cancer, and is not proof of it: an enlarged prostate (benign prostatic
hyperplasia), other common prostate problems, and certain medicines all raise
it. In general the higher the PSA the likelier cancer is — **and a low PSA is
not a guarantee that there is none.**

Digital rectal examination. A provider feels the prostate through the
rectal wall for lumps or anything unusual. A DRE can reach only one side of
the prostate.

Either may detect prostate cancer at an early stage. **What is not clear is
whether early detection and treatment lower the risk of dying from prostate
cancer.** That sentence is the whole reason screening here is a discussion
with a provider rather than a routine.

Both sides, laid out

Possible benefits

• Finding and treating a prostate cancer early, before it spreads
• A better sense of your own risk, from the PSA level
• Peace of mind if screening suggests cancer is unlikely right now
• The option of further testing and close monitoring if it suggests otherwise

Possible harms

• A false positive — the PSA suggests cancer that is not there. That means
  worry, more tests, and often a prostate biopsy, which is the only way to
  diagnose cancer and which carries its own risks: fever, pain, blood in
  semen, urinary tract infection.
• Treatment you did not need. Screening can find a cancer without making
  clear whether it would ever have grown or spread. Treating a cancer that
  would never have caused a problem is not a neutral act: the common prostate
  cancer treatments can cause **urinary incontinence, erectile dysfunction,
  and problems controlling bowel movements**, and those complications can be
  serious and permanent.

That is the trade in full. A test that may find something harmless, and a
treatment for it that may cause permanent harm, weighed against catching the
minority of prostate cancers that kill. Talk it through with your provider
rather than defaulting either way.

Source: MedlinePlus, U.S. National Library of Medicine.