In US and "Western" English speaking "mainstream" culture, we would not normally feel a need to communicate that idea of politeness, concern, or respect explicitly with language. We would most likely trust that our listener knows we don't connect the potentially offensive thing or idea with them. We would typically not want to call more attention to it, and would probably continue talking and behaving normally to show our feelings toward the listener. This opinion is based on my experience.
If a particular situation calls for it, we could probably add the phrase "no offense/no offense intended" or perhaps "sorry to have to refer to such a thing" to show that we don't want to cause bad feelings when saying something potentially unpleasant or insulting. If any of the participants is Arab or from another high-context culture, like East Asian cultures, we might be smart or feel more comfortable adding such a phrase. The "Western" cultures tend to insult people directly rather than through subtle or indirect references, so we will worry less about the possibility of someone interpreting an indirect reference as an insult.
Beyond that, we can just try to communicate the idea with language such as "Forgive me for mentioning such a course (or "vulgar") thing/idea while talking with such a lovely/charming/pleasant/respectable person such as yourself", although that is formal language.
It will be interesting to see if some Arab person who lives in or has lots of experience with English-speaking places or situation has something to share about this. It might also be useful to find some kind of Arab social or cultural organization in an English speaking place and see if someone there has a useful response. You might search online or Facebook for something like "Arab American News", "Arab American Institute", etc., and establish contact.
