Regarding tumors and their developement
There is indeed a positive correlation between gastric reflux disease and esophageal cancer, and also between stomach ulcerations and stomach cancer. There are more than one possible mechanisms for these correlations to arise, but what you are proposing is definitely a prime suspect.

http://www.webmd.com/heartburn-gerd/news/20130523/chronic-heartburn-may-raise-odds-for-throat-cancer-study

http://www.ncbi.nlm.nih.gov/pubmed/10658066