There’s usually a whole host of inaccuracies with regards to people’s perception of cancer and the recovery thereof. But rather than addressing them all and ranting at the poor chap, focus on one.
Insensitive comments come in a range of forms, from disapproval that you aren’t listening to the completely untested advice of Joe Bloggs on the street, to one ridiculous occasion when someone refused to believe I’d had cancer in the first place.