Appeal type: Practitioner Services
Decision: Unfavorable

 
We decided that the Plan does not have to pre-approve proton beam radiation therapy. 
 
You asked the Plan to pre-approve proton beam radiation therapy. You say that proton beam radiation therapy 
is medically necessary to limit the radiation dose to the liver and to provide optimal coverage of the target 
while minimizing adjacent bowel dose. The Plan denied your request. The Plan says proton beam radiation 
therapy is not medically necessary for the patient's condition. 
 
The Plan follows Medicare rules. Medicare rules say that proton beam radiation therapy is only coverable for 
certain conditions when medically necessary. 
 
We asked our physician reviewer to carefully review the case file and apply the relevant Medicare rules to 
determine if the Plan was correct in denying the request to pre-approve proton beam radiation therapy. Our 
reviewer says that proton beam radiation therapy is not medically necessary in this case. Our physician 
reviewer said that proton is the charged nucleus of a hydrogen atom (hydrogen atom minus an 
electron).  Charged particles (such as protons and carbon) can be used to deliver therapeutic 
radiation.  Standard radiation is delivered with a linear accelerators (LINAC), which deliver photon therapy 
(akin to high energy light), while protons (and other charged particles) are generated from a cyclotron.  The 
difference between proton and photon irradiation is that the protons (or charged particles) stop more abruptly in 
the tissue (Bragg peak) so there is less exit dose through normal tissue. 
 
The use of proton therapy is an accepted radiation technology, that has proven efficacy and tolerability. Proton 
therapy is not investigational- it is simply a different means to deliver radiation. Intrahepatic 
cholangiocarcinoma (IHC) is treated similarly to hepatocellular carcinoma (HCC) 
 
Whether or not proton therapy (in general) affords any benefit over conventional radiation therapy is a heated 
issue, with quite disparate opinions among experts in the field. The medical documentation in this case does not 
show an unacceptable non-proton (photon) based plan. There does not appear to be a clinically meaningful 
benefit of proton therapy over photon therapy. Clinically meaningful reduction in the kidney volume receiving 
>20 Gy, and bowel volume receiving >40-50 Gy can warrant consideration of proton therapy). Adhering to 
normal tissue constraints is standard of care and when a non-proton based plan cannot achieve that (with 
optimal beam weighting and orientation) and a proton plan can, proton therapy can be considered medically 
necessary. 
 
The most recent National Comprehensive Cancer Network (NCCN ) guidelines for hepatobiliary cancers state 
that proton beam radiation is an acceptable option for intrahepatic tumors. but does not specify the need for 
proton therapy over intensity-modulated radiation therapy (IMRT) or hypofractionated image-guided 
radiotherapy.   
In this case, while this patients liver tumor is in close proximity to normal tissues, the case file does not 
demonstrate that proton therapy is needed to avoid exceeding tolerance doses. In addition, while proton therapy 
lowers doses to surrounding tissues, the case file does not show a reduction in dose exposure that would equate 
to lower risks.   
 
Thus, proton therapy can be considered medically necessary when justified with quantitative dosimetric 
information that shows a clinically meaningful reduction in radiation dose exposure of normal tissues.  In order 
for toxicity risks to be reduced, there should be a clinically significant reduction in dose to critical structures, 
with an evidence basis of benefit with dose reduction.  
 
We looked at this physician's review, the file, and Medicare rules. Based on this information, we decided that 
Medicare rules for coverage of proton beam radiation therapy have not been met. Therefore, we decided that 
the Plan does not have to pre-approve proton beam radiation therapy.