LINAC vs GK

[becknell]

Does anyone know of any studies out there that compare outcomes/accuracy of LINAC vs GK? I'm looking for hard evidence of a difference. Duke, where my spouse had his surgery, only has LINAC. There is some tumor residue that may possibly require radiosurgery at some future point. His doc said he thinks LINAC is as good as GK, but said that if we really want GK and (assuming he eventually needs the radiosurgery) he would refer us to U. of Va. So I'm looking for hard evidence that there is a difference.

[jamie]

Both deliver ionizing radiation and have the same effect on tumor cells. GK uses gamma rays and LINAC uses x-rays. 

[becknell]

But is there a difference in accuracy?

[jamie]

There is, depending on the LINAC machine. The only LINAC machine I know that is as accurate as GK is the CyberKnife. I'm not sure exactly how much less accurate the other machines are, but if you want to be assured the best accuracy, you want GK or CyberKnife. With GK, a metal frame would have to be screwed into your spouse's head, which is not the case with CyberKnife. Also CyberKnife allows fractionated treatment usually over three days, which is believed to lessen the chances of nerve damage.

[Larry]

This is an interesting topic. I am in Sydney and the specialist here uses Linac. he didn't say why he used it v's the other methods but identified that there were no real differences between them. I'm not quite sure about that. I'm not a medico but i would have thought that a controlled dose over a three day period would be less damaging on the good cells and nerves than a one off hit of say 3 times the Gy levels. CC posted an interesting report on this. As there is only one hospital in Sydney that provides this treatment, I will be going to melbourne for another independent opinion. I have learned that you need to research these things yourself rather than rely on one doctors' opinion. I wish i had the benefit of knowing of this web site before i had my initial surgery 3 years ago.
Anyway, one interesting comment that the specialist did tell me was that he has noticed an increase in fatigue following Linac treatment. maybe you could raise that with your doctor.

Larry

[jamie]

Here ya go becknell:

http://www.anarchive.org/spread.htm

Don't know if you guys are considering CyberKnife or not, so I won't waste space providing accuracy comparisons between CK and GK, but if you would like to see some, let me know.

[Larry]

Jamie,

I appreciate your postings and help. At this point, i have probably read enough about the different machines to be tottaly confused. I say that a little flipintly coz, without everyone's comments and directional pointing, I would be none the wiser on this stuff.

From my understanding of these machines, the accuracy is hardware and also software dependent and how well the machines are maintained. The accuracy of the various doses of radiation be it through any machine type is largely dependant on the programmers and also the maintenance on the machines. Unfortunately, this info is not that readily available. The other issue is the accuracy of the Cat and MRI scans done pre procedure to pinpoint the centre of the tumor.

My summation here is that if you are comfortbale with a particular radiologist, they should be able to determine the most appropriate procedure for you. This is dependant on how "money greedy they are".


Larry

[jamie]

Hi Larry

I'm sure the mechanical maintenance records at a center of excellence are available if one wanted to see them. They are maintained by nuclear physicists, who are extremely thorough (they've even been called "anal retentive" lol), from what I've read. Before my procedure, they thoroughly checked the CyberKnife before firing it up. I guess it just depends on how much faith you have in modern technology. I'm quite confident that people screw up more often than the machines.