I've seen Japanese women address their husbands with the -sama suffix. Would it be appropriate for a man do the same in some cases? In which context can this be used?
～様 is an honorific and can be easily thought of as a more respectful version of ～さん. It is gender neutral, so it can be used by both men and women when addressing either gender.
It is often used when addressing someone of a higher social position, or someone for whom you have high regards. On a day-to-day basis, it's commonly used to address customers.