Only if the subject comes up in conversation. 
What does "comes up" mean?

Something came up and we had to deal with it straight away.
What does "came up" mean?

I guess in the end my decision will come down to what my professor recommends.
What does "come down to" mean?

depend mostly on or be influenced most by

I came across someone who's done an almost identical study.
What does "came across" mean?

depended mostly on or be influenced most by

I spilled some tomato juice on the tablecloth. Do you think it will come ..... if I put it in the washing machine?

Some very shocking facts have come ..... about government corruption, thanks to an investigation by a national newspaper.

Only if the subject comes up in conversation. What does "comes up" mean?