Core Needle Biopsy of the Prostate
How is the examination performed?
Biopsy via the rectum: an ultrasound pro
be is inserted into the
rectum and used to feed a hollow needle forward and into the
prostate through
the anterior rectal wall.
At least 8 samples are taken in a core needle biopsy, if the
procedure is being repeated, at least 10 samples. If there is a
suspicious area, then additional tissue cylinders will be extracted.
Tissue is removed with so-called biopsy-guns which function very
quickly, in fractions of a second, and therefore do not cause much
pain.
The tissue is extracted through the rectum. For this reason, you
will also receive an antibiotic prophylaxis (pills or injection).
Infections are seldom (fever in about 2-3% and urosepsis in 0.2% of
patients).
What preparations are necessary?
If there is increased bleeding tendency as a result of
anti-coagulant medication, the procedure cannot be carried out
immediately due to danger of bleeding. The medication (e.g.
marcoumar, thrombo ASS etc.) must be discontinued and the
appointment will be rescheduled depending on blood coagulation.
For trans-rectal biopsies, the rectum should be empty (relatively
clean) as far as possible, otherwise a laxative must be given and
the procedure carried out later.
If a short anaesthetic is planned for the procedure, you will be
advised separately of all details and risks relating to the
anaesthetic.
What complications are possible?
In most cases the procedure does not result in any serious complications. In spite of greatest care, occasional complications can arise. The following should be mentioned:
- Bleeding after the insertion, above all through the rectum in the case of internal haemorrhoids, which in rare cases requires temporary compression by tamponade. Rarely, heavier bleeding (haematoma) may occur between the anterior rectal wall and the prostate, this usually resolves spontaneously.
- Occasionally the urethra or the adjacent bladder may sustain small puncture wounds, which are self-closing. For a short time, urine may be bloody. Drinking abundantly is sufficient to wash this away. Only in rare cases is an endoscopic haemostasis necessary.
- Infections can arise through the puncture of the prostate. Germs and intestinal flora can be introduced through the puncture and occasionally trigger a local infection or even fever. This can usually be controlled with antibiotics. Very rarely, a prostatic abscess which requires surgical drainage may form. Severe febrile reactions of the entire organism (sepsis) which require intensive medical treatment are extremely seldom.
- Oversensitivity reactions to the local anaesthetic or the antibiotics are rare. Stronger reactions which may necessitate intensive medical treatment are extremely seldom.
What are the chances of success?
The fine tissue examination usually provides clarification of the
suspicious palpation or raised PSA-count as tumour-markers. Cancer
is found in only about one third of cases. Further possible causes
include: chronic infection (prostatitis) and benign, micro-nodular
enlargement of the prostate.
In rare cases, it can happen that the biopsy misses the cancerous
tissue in the suspicious site, thus leading to a false negative. For
this reason your physician will follow up the examination carefully
and if necessary do a rebiopsy.
The biopsy sample may under some circumstances be insufficient for
the evaluation, so that a repetition of the procedure is necessary.
When the result of the fine tissue examination is available, your
physician will discuss all further treatment options with you.
What should you do?
After the procedure, you should take it easy physically. This
also applies to sexual intercourse over the next two days (seminal
discharge may be bloody), as well as hot baths or sauna. As
applicable, take the antibiotic prescribed by your urologist
according to the instructions.
In the case of symptoms like post-procedural bleeding from the
rectum, an increasing (as opposed to decreasing) amount of blood in
urine, raised temperature or fever, circulatory problems or pain,
inform your urologist without delay or have yourself taken to him.