I might be a little late in posting this but have you had a colonoscopy? That is a screening test for colon and rectal cancer. When the doctor takes a look with the scope, they can also remove any unusual growths at the same time and send them for biopsy. It takes 20-30 minutes and is done under anesthesia. I really don't see how your doctor can diagnose "warts", high risk or otherwise, unless he/she actually did a biopsy. Once the tissue is examined by a pathologist, your GI doctor will recommend follow up colonoscopies ranging anywhere from 1 year to 10 years, depending on your age and risk factors. I STRONGLY encourage you to have this procedure. There is absolutely no reason to guess about whether or not you should be worried, unless it is for financial reasons.
I was recently misdiagnosed with warts (visible and external)and the only reason I know is because I insisted on a biopsy before treatment. I just had normal skin tags.
You probably do have internal warts since you're already being treated for that, but it could also be something else and since your doctor can't see up there, and feeling a growth is not an acceptable diagnosis for warts, I think someone should take a look. Good luck.
I had similar issue with girlfriend, here is post:
http://www.medhelp.org/forums/STD/messages/2655.html
From what I understand, the strain that causes warts is not the cancer causing kind. Do you realize how many people probably have internal anal warts but don't even realize it?
Although not real common, anal warts--including intrarectal warts--occur from time to time in straight men with no history at any time of sex with other men. Warts are caused by low-risk HPV types, i.e. the types not associated with cancer, so your risk of anal/rectal cancer probably is low. On the other hand, there are exceptions, and if you have one HPV type, you might have others. Presumably you are seeing a provider who knows all this, and probably already told it to you. Many protologists are quite knowledgeable about these issues, but if you're not certain your provider is up to speed, seek a second opinion from one who is.
This problem does not, in itself, suggest a high risk for HIV. However, genital/anal HPV is an STD, which means that at one time or another you have been at risk, however minimally. All sexually active persons should have an HIV test from time to time, so if not done, ask your provider about it. But I really don't think you have anything to worry about along those lines.
Good luck-- HHH, MD