Radiation therapy for prostate cancer: What to expect


Uploaded by SunnybrookMedia on 28.06.2011

Transcript:

I'm Dr. Danny Vesprini, Radiation Oncologist at Sunnybrook, and Assistant Professor
in the Department of Radiation Oncology at the University of Toronto. I treat
prostate cancer and other malignancies.
Prostate cancer is the most common malgnancy diagnosed in
men in North America. The two main options of treatment are
either radical prostatectomy with surgery or radiation.
Radiation, whether it's external radiation or brachytherapy
all works on the same principle that it's energy. Much like light shines through
the cells and then preferencially kills
cancer cells, whereas normal cells can repair themelves.
Here at Sunnybrook we see and treat over
a thousand men a year. It would be probably the
biggest radiation prostate facility certainly in Toronto if not
Ontario. It's an area of expertise
and excellence at our centre. We have
eight radiation oncologists that treat prostate cancer alone.
There are three main types of radiation we do here at Sunnybrook, the first being external beam radiation
which is probably the most common. That's where men lie down
have external radiation, much like an x-ray. The second is called
brachytherapy, or internal radiation, where radioactive seeds are inserted permanently
inside the prostate. That's for select men with low-grade disease.
And for low-risk disease. And the third is a combination of external-beam radiation therapy
as well as temporary brachytherapy, or high-dose
radiation, or HDR, where the radioactive seeds are temporarily
placed into the prostate at certain areas and that's used in combination with external
beam radiation therapy for very select men with certain features.
With external beam radiation
therapy, the process entails
coming in, having a consultation with the radiation oncologist
being marked up or planned and that involves having a special CAT scan
done where measurements are made, small tattoos are put on the skin for
localization. A scan is done as long as
men have filling of their bladder and an adequate
and some of the things we are very particular regards to primary
radiation. Men have their scans, the tattoos are made permanent
they go home and then within the next week or two
the oncologist, the radiation therapist will go over the plan
and devise a specific plan based on that person's anatomy
mapping out the prostate, bladder and the rectum which are the two main
organs that are at risk when we treat men. Then men will typically start
about two weeks later. Something called a VacLock bag, that's a little
that's essentially a bag of beans where patients are
laid onto and their legs and hips are molded around
this device. All the air is sucked out so that allows them to have a very cosy
cushion that is to their anatomy
and minimizes them from moving around during radiation.
Each treatment lasts between about
60 seconds, so we have new technology that allows us to get the radiation done very quickly
or traditionally seven or eight minutes. The radiation
plan is devised of seven different angles
around the person's body with this scanner
moving around and each time that beam
stops in a certain angle
Before every radition treatment this scanner will go completely
around the patient, provide a small CAT scan
so if the prostate is more than two millimeters away from where it was when we planned the radiation
that adjustments can be made to make sure we are very precise.
This decreases side effects. Men will typically come in Monday
to Friday for eight weeks if they have a prostate
we're treating for cure. Six and a half weeks if we're treating those men after surgery
and we give small doses each day so that a certain percentage
of the cancer cells are killed, but in the intervening 24 hours
normal cells can recover to minimize side effects.
The patient sees the physician to go over the bowel
and bladder symptoms and things like that and be
followed long term.
When we treat men with a combination of external beam radiation therapy
and the HDR brachytherapy, the external beam component
is the exact same. But then what men get is
an ultrasound of the prostate to map out
the prostate. They then come in for the HDR
brachytherapy component of treatment, which involves a general anesthetic so men are
put to sleep, catheters are placed inside the prostate and then a small
radioactive seed is inserted along those catheters at certain intervals
to deliver a very high dose of radiation to that
prostate in a single setting. Men are taken out, woken up
to make sure they can pee and they go home. In general, the external radiation will start
two weeks after that or in some cases before
the brachytherapy depending on availability of that resource.
It's not available in every centre. It's slowly becoming more available because it's been found to be
a very effective way to treat prostate cancer, specifically those men who are young
and have more aggressive disease, so that's what we select fore
now.
The last option, which is very popular for men with very low-risk
disease is called permanent seed brachytherapy, or low-dose rate
LDR, that's where the seeds are permanently placed inside the prostate
and it involves men coming, being assessed by ultrasound, having
pictures taken essentially and then a plan is devised based on that person's prostate
and they come in a week or two later. The seeds have since been ordered and received
and are then placed inside the prostate at the appropriate areas
and a CAT scan is done afterwards to make sure the seeds are where they are supposed to be. And that
radiation stays active for several months. Men do have to carry around little cards
saying they are radioactive in case they go into airports and things like that, but it's a common thing
and the authorities are aware of that. Men are asked to strain their urine for a while
because there is a small chance one of the seeds will fall out, which doesn't pose a risk to anybody
but we take all the precautions necessary. This is for men with low
grade disease, relatively low PSAs and men that have
prostates that aren't too big. Because if the prostate is too big, then the side effects of treatment go up.
Radiation makes
people tired because some of our bone marrow is in our hips
and the blood is suppressed a little during radiation, not enough to cause
infections, but it's probably one of the reasons why guys get anemic and a bit
tired by the end of radiation. But also coming here every day for weeks
is tiring.

It's a good relatively non-invasive
way to be treated. It's time consuming
but in general a short amount each day.
It avoids surgery in those men that don't want to have the side effects of surgery
or are not surgical candidates and it provides
at least what appears to be the exact same chance of living to whatever ripe old age
they were supposed to live in the first place. Less in one out of ten men now will need to have
a medication because we've able to keep radiation off the rectum and the bladder
and that's despite the fact we've increased the dose a lot over the last
few years as well. There's more sessions, but less
side effects. So we in fact, quote cure more men,