I totally agree... I am a non smoker, non drinker, vegetarian who used to work out daily. In rads right now so my one hour work out has turned into 30 minutes and two daily dog walks with a yoga thrown in here and there. I had a bad molar on my left side for years... One visit to the dentist he noticed a white thickened patch and sent me to an oral surgeon they removed it.. Biopsied it... Came back as thickened skin - perhaps the hyperkeratosis? Brian mentioned? So once it was removed things seemed to be okay.. (this was 2002) it was sensitive in that area but no real problems. Jump ahead to 2005... I had a that bad molar capped ( it was merely a shell of a tooth before) from that point on my tongue was irritated - not badly but enough to be uncomfortable. I let it go thinking it was because of the molar... Though I had them file it down once or twice with no success. This went on for 2 - 3 years. I finally had a biopsy - I could feel the thickened mass there under my tongue but there was a large area of dysplasia too. Biopsy came back inflamed tissue. I then went and had that molar filed again, and I had allergy testing thinking it was related to the possibility that is was eating something I was allergic to. Well I'm allergic to a lot of things... This past summer I had the molar beside the capped one also capped... The situation with my tongue got worse, I finally had another biopsy - this one came back SCC. And the lesion was 1.5 x 2.5 cm. After I got the diagnosis I was looked at a few sites, and one of them actually listed chronic irritation as a cause of scc.

I totally believe that chronic irritation can cause cancer. That's what happens with lung cancer... Chronic inflammation leads to cell change. Also isn't that why cancers of the tongue, lip and oral mucosa are blamed on smoking? That's what smoking does, chronic inflammation, and irritation of the lungs mouth and lip ? Same principal different cause. I used to be a nurse and a, familiar with the workings of the body, so my first question of course was why?

There should be more studies on this.