Welcome Peter! It's a small world -- I was living in S-Vaihingen, working at Patch Barracks (Kurmaerker Kaserne), when my first tongue lesion was noticed and biopsied by US military doctors in 1990, but didn't result in an SCC tumor until 2005. I've also lived in Waldenbuch and we had a small, informal German-American Club in Schoenaich, where we celebrated an American Thanksgiving every year, with Americans bringing turkey, Germans and others bringing their ethnic favorites. Your English is excellent, far better than my German!

You may be able have your cancerous tissue examined to determine the presence of HPV. Females, of course, can also have their PAP smear examined for the virus.

Good luck with the remainder of your IMRT treatment -- The worst is yet to come in that regard and there is much information here in this forum about it. Like sunburn or cooking with a microwave, even once the treatments are done, you will keep 'cooking' for another two weeks and then it will start getting better.