Cancer - Prostate
The prostate is a small gland about the size of a walnut at the base
of a man’s bladder in front of the rectum. It surrounds the urethra
just below the bladder. The prostate secretes a fluid that contributes
up to one third of the total volume of the seminal fluid released when
a man ejaculates. Prostate cancer is a condition in which some of the
cells of the prostate reproduce far more rapidly than in a normal
prostate, causing swelling or a tumour. If left untreated, prostate
cancer cells eventually break out of the prostate and invade other
parts of the body (known as metastasis).
Prostate cancer is one of the slower growing cancers and typically
affects men over the age of 50, although it can affect younger men in a
form that can be very aggressive. For many men, a diagnosis of prostate
cancer can be frightening, not only because of the threat to their
lives, but because of the threat to their sexuality. However, if
prostate cancer is detected early, whilst it is still confined to the
prostate gland, there is a better chance of successful treatment with
minimal or short-term side effects. Successful treatment of cancer that
has spread beyond the prostate gland is more difficult.
We know that prostate cancer is regulated by hormones, since males who are castrated prior to puberty do not develop prostate cancer.
Research suggests that there is a complex interplay of factors that
have a causative role in prostate cancer. They include genetics,
ethnicity, hormones, diet and the environment.
The influence of our genes on prostate cancer development is under
active investigation, both at the Garvan and around the world. Prostate
cancer often does not produce any symptoms in its early stages, which
is why many cases are not detected until it has spread beyond the
prostate.
Most men tend to accept the onset of one or more of these symptoms
as being a natural consequence of ageing, but they may also indicate a
problem with the prostate gland:
- Waking frequently at night to urinate or a sudden need to
urinate
- Difficulty in starting or stopping urinating or a slow flow of
urine
- Discomfort, pain or blood when urinating or ejaculating • Decrease
in libido or reduced ability to get an erection.
Factors that increase the likelihood of developing prostate cancer
are:
- Age - It is most common in men over the age of 50
- Genetics - Regular testing from the age of 40 is advised if you
have at least one first degree relative who has had prostate
cancer
- Ethnicity - e.g. European men have a much higher chance of
developing prostate cancer than Asian men
- High levels of testosterone - testosterone naturally stimulates the
growth of the prostate
- Diet - a high-fat diet and obesity may increase your risk of
prostate cancer
As part of a regular check-up, in men over 45, a digital rectal
examination (DRE) is recommended in order to detect any irregularities
in the prostate. This may be an uncomfortable examination but is rarely
painful. An enlarged gland will feel hard and possibly irregular in
shape.
A Prostate Specific Antigen (PSA) test may be requested if any
abnormality is found. This measures a protein in the blood which rises
in concentration when there are prostate problems. In themselves, these
two tests will not distinguish between cancer or a benign enlarged
prostate and so, if an abnormality is found, an ultrasound scan will be
carried out. A biopsy will then determine if the prostate is cancerous
or benign.
Information from diagnostic tests helps to determine the best
treatment approach. Depending
on the stage of the cancer development, a number of treatment options
may be offered:
- Observation only (called ‘watchful waiting’) – monitoring the
disease through regular check-ups, but delaying treatment until the
disease shows signs of progressing or symptoms become troublesome
- Radical prostatectomy – an operation to remove the prostate gland
and the immediate surrounding associated organs, such as the seminal
vesicles
- External beam radiotherapy
- Radiotherapy using radioactive ‘seeds’ of Iodine125, which are
permanently inserted into the prostate
- An operation to reduce male hormone production by removal of one or
both testicles
- Medicines to suppress the production and action of the male sex
hormones
We have taken a multidisciplinary approach that utilises the
expertise of a number of cancer researchers within and outside Garvan,
including clinicians and pathologists from a number of Sydney’s major
teaching hospitals.
Thanks to collaborators from Melbourne, we have access to DNA
from over 4000 Australian men. Our cutting-edge technology enables us
to investigate a large number of genes across the extensive collection
of samples. This valuable resource helps enable us to identify the
clinical and molecular markers of prostate cancer prognosis. This
knowledge will enable future prostate cancer patients to be matched up
more effectively with the best possible treatments, thereby improving
the outcomes.
In addition to improving early prognostic markers of prostate
cancer, we are researching predictive markers – clinical and molecular
indicators that allow us to evaluate the potential success (or failure)
of a treatment.
News
Study shows that prostate cancer increases the risk of bone fracture
MEDIA RELEASE:
14 May 2008
As unlikely as it sounds, scientists at Garvan have shown that there is a link between prostate cancer and a higher risk of bone fracture. Their study suggests that men with prostate cancer face a 50% higher risk of fracture, which increases to nearly 100% if they are receiving androgen deprivation therapy for their prostate cancer.
The molecule that can switch appetite off and on
05 Nov 2007
Researchers from the St Vincent’s Campus have identified the molecule responsible for the extreme weight loss common in late stage cancer. The findings published online in Nature Medicine suggest it may soon be possible to prevent this condition, giving people the strength to survive treatment. Conversely, the knowledge also suggests a way to switch off appetite in obese people.
