Jay K. Harness, M.D.: An important concept that has been filed for several years now
with radiation therapy is called boost treatment.
Why is this concept important?
Well, in lumpectomy or partial mastectomy, if we are going to have a recurrence in the
breast then 85 perhaps 90% of the time, the recurrence will actually occur right in the
same neighborhood where the original cancer was.
So the concept that emerged then was well, if that is the case, let's go ahead and add
some extra radiation therapy right just where the cancer was, which was one of the reasons
why the surgeons always left clips to mark where they were in the breast.
The concept or the term used here is called boost and certainly, over the past many years,
the way the boost has traditionally been done is that at the end of five weeks of radiating
the whole breast, the last week or more would be for boosting the area where the cancer
was"and this was done again with electrons as a wonderful energy source done in the vault.
The electrons have to travel through the skin in order to get to the target area, as well
as the fatty tissue underneath.
One of the disadvantages of this is, not only damaging the overlying skin and subcutaneous
fat, but the radiation oncologists were always worried whether they were actually hitting
the target.
In other words, they were worried about a miss, in other words not fully getting the
area.
Therefore, for those particularly in Europe and some of my distinguished colleagues from
Salzburg, Austria, I got the concept, well, wait a minute, we have a linear accelerator
operating room, why don't we start doing the boost therapy at the time of doing the lumpectomy?
They began this over a decade ago and have accumulated some absolutely fantastic data
and this approach now has spread to other areas within Europe.
What is the advantage of doing the boost at the time of the lumpectomy?
Well, the surgeon is right there.
The surgeon literally sees where the target is, the surgeon knows where he or she took
the cancer out and therefore, when you put the cone in to help guide the radiation therapy,
you are literally right on top of the tissue that is at risk, where there could be little
microscopic cancer cells left behind. he other advantage of this is that you are not damaging
the overlying skin and subcutaneous fat tissue because it is pulled out of the way.
So there is going to be more and more use certainly in Europe and I believe more here
in the United States of doing the boost therapy in patients who need whole breast radiation
therapy at the time of doing the surgery, in other words using IORT as a very effective
way of delivering a very accurate boost.