Why not targeted radiation? - 1268737

Hi knic,

It's not possible for our faculty to guess about someone's oncologist's decision making process.

Dr. Loiselle wrote an informative post on the subject that starts, "For non-small cell lung cancer patients with multiple brain metastases, the standard approach of whole brain radiotherapy is not necessarily standard for each and every patient. Each patient’s specific situation may sometimes be best approached with various combinations of surgery, radiation, medical/systemic therapy, and non-cancer directed treatment.

The best course of treatment depends on many factors. Key aspects of a patient’s situation include age, how well the patient is doing in general, whether they have other sites of metastasis other than the brain (and whether those sites harbor active cancer), how extensive the brain metastases are in size and number, and whether they are experiencing symptoms" http://cancergrace.org/lung/2011/09/11/brain-metastases-in-lung-cancer-…

The best way to know what the oncologist is thinking is to ask him/her personally. If your not comfortable after that a second opinion at a major teaching hospital may be in order. However brain mets can cause difficult symptoms and care sooner than later may also be important.

All best,
Janine

knic,you didn't mention that dosage amounts or sizes here as you did on Inspire. This might be helpful.
Take care, Judy

knic, I've got word out for our radiation onc to comment but as you can imagine he's very busy and not unusual to take a day or more to respond. Radiation dose measurement are given in "Grays" or GY and different amounts can be given at one session.

Further reading to help understand what's happening (and maybe help explain what's happening in your dad's case can be found in the links below. The second link being the one also posted in the first link.

http://cancergrace.org/radiation/2013/05/05/dr-scott-on-wbrt/
http://cancergrace.org/radiation/files/2013/05/WBRT-review-from-Scott.p…

Janine

knic, Just checking in to see if you've spoken to your dad's radiation oncologist or had a second opinion. I'm pretty sure we can have Dr. West comment today.

All best,
Janine

Hi knic,

Just to clarify: whole brain radiation can be given in varying numbers of sessions at larger or smaller doses per session. For example, 5 sessions of 9 GY (or "Gray") each is the same total amount of radiation as 15 sessions of 3 GY each. In Europe it is not unusual to see WBR given over the shorter time period, but that doesn't necessarily mean a lower amount of radiation.

JimC
Forum moderator

Right. What Jim is describing is the concept of "biologically equivalent dose" (BED) in radiation, which is a product of both the number of treatment sessions, or "fractions", and the dose per fraction. In fact, when treatment is given over fewer fractions, a lower absolute dose is used to reach an equivalent BED. So it's actually not that you give 6 Gray (the basic unit of dosing radiation, abbreviated Gy) x 5 fractions to get the same BED as 3 Gy each x 15 fractions, but rather maybe 5 fractions x 3 Gy per fraction to equal the BED of 15 fractions of 2 Gy each.

As Jim indicated, the practice differs in different health care systems. WBR administered over 10-15 fractions is common (especially 15 fractions, 3 weeks of Mon to Fri) in the US, but in Europe as well as Canada, it's pretty standard to give WBR over just 5 fractions in a single week. There's a higher risk of acute side effects like headache, fatigue, and perhaps transient cognitive problems, but efficacy is more similar than different across the different common schedules.

You can learn more about brain radiation in this podcast:

http://cancergrace.org/radiation/2011/04/29/dr-minesh-mehta-radiation-o…

Good luck.

-Dr. West