My name is Urban Emmenegger, I'm a Medical Oncologist here at
the Sunnybrook Odette Cancer Centre. I'm specializing in the treatment of prostate
cancer and the way I do that is different from some of my colleagues, I use
mostly hormonal treatments and I use chemotherapy. Prostate cancer is a very specific
disease in that most prostate cancer cells actually
depend on male hormones so they can really proliferate and also they
can cause symptoms in a patient, and this why
hormonal treatments are so efficient in this type of disease.
By hormonal treatments, we actually try to reduce the amount of
circulating levels of male hormones and this can be done
in different ways. It can be done by giving medications that silence the testes
which are the origin of 90 percent of male hormone.
The remaining 10 percent are coming from adrenal glands.
By using medications that are either injected under the skin of the tummy or
injected into the buttocks, we can
impair the signals that go from the brain to the testes and actually
tell the testes to produce male hormones.
Sometimes this is not enough and we use other agents that block the activity of
the hormones so they are still around but they can't actually activate the
prostate cancer. There are new medications around that also help to reduce
the amount of circulating male hormones that come from other
sources, for instance, from the adrenal glands. And what we often do is that
at some point we start to combine many of these things so that we can
have a low as possible hormone levels in a male
body knowing this is one of the most efficient ways to treat
prostate cancer.
Hormone treatment can be used for different reasons in prostate cancer. It
can be used in patients that undergo for instance radiation therapy
but that have a certain risk that despite radiation therapy
although the cancer is localized the cancer cells might start to grow outside of the
prostate or might start to grow back at the same place where is had been before.
By using hormonal treatments together with radiation therapy we can improve
the results, so actually you can use it to cure men from prostate
cancer. The patients that I see in my clinic are slightly different
as these are patients that either had at some surgery or they had
radiation therapy, some with hormones sometimes without hormones,
but the treatment failed and the cancer is coming back. So as opposed to patients
that have hornone treatment to reinforce the effects of radiation therapy
in patients where prostate cancer has spread beyond the prostate
we use it for keeping the cancer as
slowly growing as possible. But we also know that at some point even
this treatment is not enough to keep cancer under control. And patients that have
signs of prostate cancer growing back, they will start on what we call
hormone injections, and sometimes they also take tablets
at the same time, sometimes they start both treatments together and then they stop
the tablets, and with this treatment
more than 90 percent of patients will have a significant slow down
of the cancer growth that usually lasts for around
one and a half to two years. If this treatment is no longer enough
or is no longer potent enough to keep the cancer under control, this is
when they usually refer to see a medical oncologist and what we do it
usually assess to get an idea where the cancer is
and if there are any places where the cancer could make harm
in the weeks or months to come and then we often change the treatment
in the sense that we add other medications that can rienforce
the effects of the hormone treatment.
Chemotherapy is usually reserved for patients
that are close to having symptoms or already have symptoms
from their prostate cancer. Chemotherapy can be administered quite
safely and has a relatively high chance of helping patients in the
order to 50 to 70 percent. The chemotherapy used for prostate cancer
does not make people feel nauseous as some other chemotherapies
can do.
A question I often hear is that when we start to discuss
starting patients on chemotherapy is that do I need to continue
with hormone treatment. And the rule is that we actually recommend to continue
with hormone treatment for a number of reasons. One is for instance
if you have an interest in being a candidate for clinical trials, they need to
continue on hormone treatment as this is usually one of the inclusion criteria.
And there is no definite evidence, but there is
evidence that actually chemotherapy, together with hormone treatment, is as strong
than just chemotherapy alone.
The idea behind using this type of treatment is actually
that men have the quality that should be almost close
to as it had been before. Over the last few years actually we have
really done major advances in this area. We have now
agents that are more potent than agents that we used in the past
and that are more specific. So with all these new medications
coming on the market, and they have been tested primarily in patients
with advanced prostate cancer, the big hope is that if we
start to use them in patients with localized cancer, we might be able to
increase the rate of patients that are cured from prostate cancer.