WBR for Brain Mets - 1255225

njliu
Posts:142

May I ask if WBR is performed to (1) relieve the symptoms; (2) retard the progression of the brain mets; or (3) both? What is the statistics of its effectiveness in dealing with brain mets? Thank you in advance for any advice.
NJ

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catdander
Posts:

NJ, I hope your wife is feeling alright.
The answer is both. Here is a link that describes brain met treatment. In the comment section there's a statement about stats by Dr. Loiselle, "In general, we can control up to about 80-90% of known individual brain metastases with various combinations of surgery and radiation. Whole brain decreases the risk of additional metastases elsewhere in the brain from about 50% down to about 25%.". Hope this link answers your questions.
http://cancergrace.org/lung/2011/09/11/brain-metastases-in-lung-cancer-…

All best,
Janine

njliu
Posts: 142

Hi Janine, thank you. I am always amazed by how resourceful you are. I read that article by Dr Loiselle earlier but I missed out the hidden gem in the comment section.
Well, the radiotherapist is of the opinion that there is this one new mets that has to be SRS'ed immediately. We however, decided to do a repeat MRI at 4 weeks apart to be more certain of the response or the lack of it from WBR treatment before we deciding.
It would be helpful if you can refer us to some experiences of people doing SRS after WBR.
NJ

JimC
Posts: 2753

Hi NJ,

It can take a while to get an accurate picture of the effect of WBR. As Dr. West has said:

"It’s not unusual to recommend stereotactic radiosurgery (SRS) after whole brain radiation (WBR) if there are one or a few areas progressing. Options are certainly limited in that setting, and SRS is a leading option. However, it’s not especially common to do WBR with a plan to go straight to SRS without even seeing the outcome of the WBR. And yes, it takes weeks to even a few months to really be able to assess the results of WBR." - http://cancergrace.org/cancer-treatments/topic/steriotactic-radiation-a…

In that same thread, Dr. Loiselle added:

"I would repeat the MRI 4 to 6 weeks out from whole brain radiation (sooner or later depends on symptoms and how disease is controlled otherwise). If there are areas of progressive or non-responsive disease within the brain, I would treat them with SRS." - http://cancergrace.org/cancer-treatments/topic/steriotactic-radiation-a…

On the other hand, if this is clearly a new lesion and/or is large and causing symptoms, there could be more need to move quickly to SRS.

JImC
Forum moderator

njliu
Posts: 142

Hi Jim, thanks. The pre MRI was done about 10 days before WBR while the post MRI was 9 weeks after which revealed one new mets. The doubt is could it be something that have grown in the 10 days between pre MRI and WBR and thus could mean stable. There is no symptom and size is about 1cm. Thus the thinking is another 2 weeks delay should be just fine and the next MRI should yield better certainty of the progression status.
NJ

certain spring
Posts: 762

Best of luck to you and your wife. I hope she is not feeling too tired from the WBR.

Dr West
Posts: 4735

I don't think I have anything to add, since Janine and Jim have provided great direction to the best information we've got here. I'm not aware of real data beyond that, just some anecdotal experience that we often do stereotactic radiosurgery (SRS) after whole brain radiation (WBR) and can see very good results.

-Dr. West

njliu
Posts: 142

Thanks to everyone for sharing of info and support.
Dear Dr. West, it is reassuring to know SRS after WBR in not uncommon and can see good result. My question is both are basically the same in delivering radiation to zap the cancer cells, why would cells not responding to WBR force would give in to SRS? Is SRS delivering heavier concentrated dose and could inflict more damage to the brain tissue on its path and surrounding that target?
NJ

JimC
Posts: 2753

Hi NJ,

SRS is delivered in a high-dose, concentrated manner, often in just one session as opposed to the multiple sessions of WBR. While the total amount of radiation in one SRS treatment is greater than that of each WBR treatment, SRS uses multiple lower dose beams which take different paths through the brain before converging on their target. So except for the lesion being radiated which gets the full dose, surrounding tissue along each beams path gets much less. With WBR, all of the brain is radiated multiple times, so the radiation received by the entire brain is greater than that received by surrounding tissue as a result of SRS.

Hope that helps,

JimC
Forum moderator

Dr West
Posts: 4735

Jim's exactly right. Essentially, SRS delivers a higher dose in a very limited area, which is appealing if there's just one or very few areas to treat, but it's less ideal if you need to treat many areas effectively, especially since the presence of many areas involved at once is associated with a higher risk that there are also other areas of disease that might not be visible yet.

-Dr. West

njliu
Posts: 142

Thanks to Jim and Dr. West for the details. While there has been much written about the side effects of WBR, there is little that can be found on SRS. Would you please elaborate on that please?
NJ

double trouble
Posts: 573

I just wanted to say that I'm thinking of you and sending positive thoughts your way. Please keep us posted.
Debra

Dr West
Posts: 4735

There is very little risk of side effects, but it depends on the location and size of the lesions being treated. The radiation oncologist planning the treatment should be able to provide a better sense of what side effects might possibly occur.

-Dr. West

njliu
Posts: 142

Dear Dr. West, I read at another thread "moving forward" where you suggested holding off EGFR TKI for a couple of days before and after SRS while there is another post of yours indicates that concurrent Tarceva and WBR is fine. May I confirm that this it correct and the difference is due to the worry of SRS radiation of about 20 grays delivered at one shot vs the much lower individual shots of less than 3 grays each in WBR?
Thanks.
NJ

Dr West
Posts: 4735

That's exactly right. WBR is different from SRS, and it's inappropriate to extrapolate from one setting to another. Even with WBR, my preference is still to hold Tarceva, just to be safe, even if the limited data suggest it's not excessively dangerous to have them overlap.

-Dr. West