This is where becoming a pathologist is somewhat difficult for the general feeling of 'doing good' for humanity. The vast majority of time I am diagnosing patients with the worst news of their lives. Every day when I call other physicians I introduce myself and they think (or often out loud) say "oh noooo". It is so incredibly rare I call to give good news, but I treasure those calls every time.
Still. I know what I do is important. I give answers. I guide therapy. I give reasons for babies' deaths. But I so rarely give good news.