There is an article posted on the web site of the Mayo Clinic that mentions the use of low-energy laser therapy for treatment of pain. Mayo Clinic article: Mouth sores: Cancer-related causes.

Here is what Cancer.org has to say about it: "The US Food and Drug Administration (FDA) considers these laser devices experimental, and allows them to be used in investigational studies based on some evidence that they may provide temporary pain relief."
Cancer.org: Laser therapy

Anyone out there heard of this concept? Anyone out there have any additional information on its effectiveness and/or on where it is offered?

I have a sore on my tongue which has been there for many weeks (chemo ended May 12) but which is not going away. It is serious enough (and looks enough like my original tumor) to have warranted a biopsy which I had a couple of weeks ago. Thank G-d, results were all clear but as I mentioned, it is not going away. I currently manage the pain with amethocaine but am always looking for longer-term, more systemic approaches.

Thanks for any thoughts/additional info.

could be a hold over from chemo? rads will make it worse i imagine. i cant help you with the pain though sorry. Im like you I prefer something more long lasting.... i found most drugs just make me sleepy they dont really eliminate pain. great news on the biopsy.... sorry you are still going through this there is another woman on the forum who also has it in the skin on her neck. very scary... hugs and healing vibes to you.