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Not Vizsla specific - but to clear some common misconceptions;
Castration of a dog will not prevent prostate cancer, and it has been reported
that the risk of prostatic cancer may be increased in neutered males
[1,2,6].
Castration by removal of the testes will only prevent two things - your dog
cannot get cancer of the testes, and he cannot become a father. However,
most 'prostate problems' are more common in entire dogs than in
castrated males. What do we mean by 'prostate problems'?
Possible prostate problems
• enlargement of the prostate, or benign prostatic
hyperplasia (BPH)
• inflammation of the prostate, or prostatitis
• prostatic cysts
• cancer of the prostate
Benign Prostatic Hyperplasia (BPH). Having BPH
does not mean your dog will necessarily have symptoms of prostatic problems. By the age of
5, studies have found between 60-90 % plus of entire dogs have BPH. Human men also
develop BPH, and the number
of BPH affected dogs and humans increases with increasing age. In men, as the
prostate enlarges, it presses on the urethra, resulting in the well-known drippy
plumbing problem. In dogs, the growth doesn't usually affect the prostatic
urethra in this way (but may), most commonly pressing on the bowel instead. This
results in thinner, or ribbon-like stools. Castration of a male dog prevents BPH
from occurring, and is also the way to cure it. This
is because the size of the male prostate is dependent upon androgens. Removal of
androgen source, either by chemical or physical castration, results in
involution, or shrinkage, of the gland. Although up to 90% plus of entire
dogs can have BPH, they do not necessarily have any problems associated with
this.
Prostatitis or inflammation of the prostate is 'fairly common'
in dogs, and may present as an emergency. Prostatitis is far less frequent in
neutered dogs than entire dogs. Infection can be acute or chronic, and abscesses
may also occur. In chronic cases, permanent castration is a treatment-prevention choice
as it helps prevent recurrence.
Numerous types of prostatic cysts can occur in dogs.
Some may be an extension of benign hyperplasia, or they may be a true
cyst. Large cysts can be drained and surgically removed. Neutering may be recommended to decrease chances of recurrence.
Cancer of the prostate is not really that common in
dogs. By comparison, in humans it is the 2nd leading cause of cancer in men in
the US. Like many cancers, cancer of the prostate is
more likely to be found in older dogs, median age 10 years, though it has been
reported in dogs as young as 4 and as old as 17. Screening tests for prostatic disease by measuring blood
levels of prostate-specific antigen (PSA) as occurs in humans, is not useful in
dogs. Diagnosis is usually late in the course of the disease
and life expectancy of a dog diagnosed with cancer of the prostate is not very
long - University of Minnesota College of Veterinary Medicine report a maximum
survival of 5 months for dogs treated with radiation therapy [3]. Having said it is uncommon, in a study of 35
dogs without signs of prostatic disease, Waters et al [4] found one dog with carcinoma of
the prostate, so it may be more common than currently reported in the absence of
appropriate methods of detection. It has also been
suggested [5] the majority of prostate cancers in dogs have been
misclassified, thus affecting our ability to establish risk or contributing
factors. As stated above, castration does not prevent cancer of the prostate
from occurring, and recent papers [1,2,6] have found an increased risk for prostate
cancer in neutered dogs, and in
the Bouvier des Flandres breed [1].
References:
1. Teske E, Naan EC, van Dijk EM, Van Garderen E, Schalken JA
Mol Cell Endocrinol 2002; 197(1-2): 251-255.
2. Sorenmo KU, Goldschmidt M, Shofer F, Goldkamp C, Ferracone J.
Immunohistochemical characterization of canine prostatic carcinoma and
correlation with castration status and castration time. Vet Comp Oncol
2003; 1(1): 48-56.
3. Johnston SD, Kamolpatana K, Root-Kustritz MV and
Johnston GR. Anim Reprod Sc 2000; 60-61: 405-415.
4. Waters DJ, Bostwick DG. J Urol 1997; 157: 713-716.
5. Kennedy PC, Cullen JM, Goldschmidt MH, Larsen S, Munson L, Nielsen S,
editors. Histological Classification of Tumors of the Genital System of Domestic
Animals. Second Series. Washington D.C.: Armed Forces Institute of Pathology;
1998.
6. Bryan JN, Keeler MR, Henry CJ, Bryan ME, Hahn AW and Caldwell CW.
Prostate 2007; 67(11):1174-1181.
Note: the above information is not intended as a substitute
for veterinary advice.
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Prostate