There's a separate tool in GWT asking them to remove a page or directory from the cache. If the pages are not marked no-cache, they will gradually return to the cache as google recrawls.
GWT dashboard >> Help Center >> Fix an Issue >>
From here on there's a lot of overlap in where they tell you to go and what they tell you to do. You're probably the best judge of what steps you need to take. First step obviously is to make absolutely sure you've got rid of the problem and prevented it from coming back.