Thanks Bob.
I think Gav got it for me.
J

Thank you, Gav

David Hailey
May 2002

Brain tumours
Stereotactic radiosurgery treatment of primary brain tumours, other than
acoustic neuromas, was not specifically considered in the 1998 AHFMR
report.

In the present report, separate classification has been made for studies on
treatment of meningionas and pituitary tumours.

Studies on other types of brain tumour, primarily malignant lesions, are
summarised in Table 8.

It is of interest that in the eight studies that used linear accelerator
technology, four used fractionated doses.

One of these compared LINAC (stereotactic linear accelerator) with FSRT
(Fractionated stereotactic radiotherapy) and concluded that they were
equally effective but that use of FSRT (Fractionated stereotactic
radiotherapy) was associated with a lower rate of complications.

In the remaining papers, any comparisons with surgical and other
radiotherapy approaches were based on literature reports from other centres
or historical controls.

There were six studies that used the Gamma Knife, one of these in
association with a brachytherapy technique.

Five studies reported treatment of gliomas, indicating relatively limited
success.
Abdelaziz 182 comments that unsatisfactory results of SRS (Stereotactic
Radiosurgery) for GBM and fair results for astrocytomas reflect use of a
highly focal treatment for the management of diffuse, infiltrative disease.

However, Alexander and Loeffler 183 suggest that Stereotactic Radiosurgery
can result in significantly improved survival and should be considered for
patients with small, radiographically distinct and focally recurrent GBM.
The need for appropriate use with surgery and other adjuvant therapy is
also noted.

Two of the studies considered treatment of children and indicated useful
results for some types of brain tumour.

Nieder et al. 184 have published a review of treatment results for
recurrent malignant gliomas. They conclude that post-operative chemotherapy
and radiotherapy appear equally effective, but with differing toxicity
profiles; survival results of various radiotherapy methods are largely
comparable, with a trend to improved results with combined radiotherapy and
chemotherapy; and that considerable toxicity is associated with
radiosurgery or brachytherapy.

Irish et al. 185, from analysis of cases in a clinical/ imaging data base,
have suggested that there is evidence for selection bias in uncontrolled
trials of Stereotactic Radiosurgery.

Those patients with malignant glioma deemed eligible for adjuvant
Stereotactic Radiosurgery had more favourable prognostic factors and
significantly longer median survival than ineligible patients.

Stereotactic Radiosurgery (SRS)-eligible, conventionally-treated patients
with GBM and a group of SRS-treated patients had similar median survival
times (16.4 v 19.7mo).

Irish et al. suggest that a phase III study of Stereotactic Radiosurgery
for malignant glioma would be unlikely to yield a positive result and may
not be necessary.

Hello Gav,
I've reposted it.
Gad, I had to search out the acronyms and convert them.
I re-paragraphed that section of the longer article to see if I could make
sense of it.
I'm still not totally certain what one paragraph says about "radiosurgery"
and toxicity.

I picked that website for several reasons:
Alberta (I think) is more technically advanced (read: spends more on
advanced technical equipment) and based on reading another newsgroup, has
excellent neurosurgeons.
I also picked it in the hope that it would be objective (ie not trying to
"sell" a procedure.

There's another (objective, I think) one here.
It shows pictures of the machine and someone being prepared for treatment.
http://www.vh.org/adult/patient/radiationoncology/guide/04understanding.html

Risks of Linac Treatment

The radiosurgery physicians will explain the radiosurgery risks that apply
to your particular situation when they meet with you during your initial
consultation.

There is minimal if any immediate risk of radiosurgical therapy. In the
case of AVMs, the goal is to create "thrombosis" or a depletion of blood
supply to the AVM. It typically takes up to three years for an AVM's blood
supply to completely shut down. During that time, a small number of AVM
patients, about 3 percent per year, experience rebleeding. The risk of
bleeding after radiosurgery is about the same as living with an untreated
AVM and this is fortunately very small. Therefore, waiting for the
treatment to produce a cure is a common practice.

There is a very small incidence of delayed side effects from treatment
related to the radiation. Radiation exposure sometimes causes brain tissue
around the AVM to die, leading to a variety of neurological complications,
depending on the location of the lesion. This occurs in less than 3 percent
of AVM patients.

The goal in patients with an acoustic neuroma (AN) or meningioma is
shrinking of the tumor or stopping the growth of the tumor. About half the
patients with an acoustic neuroma (AN) or meningioma show a shrinkage of
the tumor after radiosurgery, while about 40 percent of tumors remain the
same. Less than 10 percent of these tumors continue to grow. Facial nerve
and/or trigeminal nerve problems develop in about 3 percent of AN patients.

Malignant tumors may also occasionally have late side effects. The chance
of such an event depends on the size of the lesion, the specific type of
tumor, as well as any previously received dose of radiation and tumor
location. The specific risk for you should be discussed with you by your
physician.

here, they're talking about metastasis...
One major consideration of the radiosurgery team when deciding whether your
lesion is treatable with radiosurgery is its size. Patients whose lesions
are less than 4 cm in diameter are potential candidates for LINAC
treatment. The decision as to whether the best treatment is radiosurgery,
surgery, or stereotactic radiotherapy requires careful consideration of all
aspects of your case by medical experts in neurosurgery, radiation
oncology, and other specialties. In addition, the patient should make an
informed decision based on the information provided by these experts.[end
copied text]

What I have been trying to accomplish is to find out if:
1) such treatment has risks/complications - I guess you would have to ask a
specialist or ask for their standard consent form, to see what warnings
they put on it (or say about the particular treatmnts).
2) how it compares to regular radiatherapy (gain, risks, costs)
3) how it compares to chemos, such as you are investigating (gain, risks,
costs)
4) whether your wife would be a good candidate. (see "4 cm in diameter
"above)

I'm not sure that I've accomplished any of it.
I'm not sure if it's available in the country where you are living.
I'm not sure if there's a certainty of only the few months extra, which
seems to be implied in that first article, or things could be different in
your wife's tumour situation.  I would sincerely like to think that longer
might be possible for your wife with this treatment now vs waiting until
the tumour grows and treating it with chemo, but I'm not an expert on any
of this.

You would have to discuss this option with specialists in your area.

I've done the best I can. If I find anything else that might be helpful or
relevant to this treatment, I'll let you know.
J

More on GBM
http://brain.mgh.harvard.edu/PatientGuide.htm (excerpt)
Types of therapy

There are three standard types of treatment for patients with high-grade
gliomas: surgery, radiation therapy, and chemotherapy.

Because grade 3 and 4 tumors have a tendency to grow rapidly, treatment
must be started as soon after surgery as is feasible, allowing time for the
surgical incision to heal. Generally, this means that patients should be
undergoing either radiation therapy or chemotherapy within 2 to 4 weeks
after surgery. An algorithm that is commonly used for treatment of
high-grade gliomas is presented on the following page.

While therapies for high-grade gliomas are helpful, at present these
treatments cannot cure these tumors.

The two major reasons for this are that tumor cells infiltrate into
surrounding brain and thus cannot be completely removed by the surgeon, and
that most glioma cells are at least partially resistant to radiation and
chemotherapy.

The goals of treatment are to:

   -remove as many tumor cells as possible (with surgery)
   -kill as many as possible of the cells left behind (with radiation and
chemotherapy)

   -put remaining tumor cells into a nondividing, sleeping state for as
long as possible (with radiation and chemotherapy)

High-grade glioma cells almost always start to grow again at some point in
time.

Thank you, Bob. It's expensive (I understand - they have to pay for the equipment
and training etc)

And glad we are that you are here with us. :-)
Happy Anniversary, Bob !
J