Are oral and oropharyngeal cancers contagious?

No: But the major risk factor, hpv virus is transmissible/contagious.

No: No type of cancer is contagious, as in passing cancer from person to person via drinking after them, kissing, oral sex, etc. However, hpv can be passed from person to person, and it has been identified as a risk factor (like smoking, alcohol, etc) in certain forms of cancer, including oral cancer.