Even though I know for a fact that the exact same areas got a second round of radiation when my tumor came back, I often read posts on OCF about doctors telling patients you can not have radiation a second time if the cancer comes back. Some posters try and defend them saying anyone who has had a second TX of radiation must be confused about where they had the radiation in the first place or that we just didn't understand our doctors.
I had thought that because I had IMRT the first time, the only way re radiation was possible was because the second time my CCC used CyberKnife since it focused better and they could minimize the pathways that had had IMRT getting even more.

Finally, here is an OCF news article about "Reirradation" using IMRT both times. So even with regular IMRT, they can do it a second time if the cancer comes back. The total median GYs are reassuring to me: 61 and 49 for a total of 110 GYs since I had 72 GY first then 25 GY for 97.
OCF re-irradation study
Those of us who have had the cancer come back certainly don't need doctors dropping the ball on treating us because they don't know you can have Radiation a second time. OCF to the rescue with a citable study instead of personal anecdotes.
Charm

@Charm
From what we have been told, Cyberknife is SBRT and may be used to re-radiate, and like surgery basically eradicate, only small tumors (normally < 3mm).

IMRT on the other hand is conformal to a field which may include a known tumor or suspicious site(s) such as lymph node chains, etc..

In a recent presentation to our H&N support group, RO Parag Sanghvi, M.D., M.S.P.H. (RMG/Cyberknife of San Diego) told us they are giving a full-course of IMRT to patients previously treated a decade or so ago with XRT, but he mentioned there are adverse side-effects.

He also said the decision to use SBRT (Cyberknife) instead of surgery for treating a recurrence is conditional and often depends on where the recurrence tumor is and surgical risks involved.

Many of the newest RT systems are able to give SBRT, or IMRT (Tomo, Novalis, Varian, GammaKnife, ect..).

don

Good info. I know all too well just how "conditional" re-radiation is since I could not get it instead of surgery but only as a follow up. My radiologist dismissed out of hand any idea I had that I could avoid surgery to eradicate a tumor that had come back in the same place after a full 72 GY IMRT.
The radiation the second time was to address the post surgery pathology report of PNI (Perineural involvement/invasion).
My concern was that patients similar to me might not get the very doable option of second radiation - as I've seen posts here where patient's doctors apparently don't believe you can have radiation a second time.
Fun acronyms like Stereotactic Body Radiation Therapy - make me think of a transit system. the old SBRT
Charm