Let's get one thing out of the way first: you don't have to tell anyone at your workplace about your diagnosis...unless. Yes, there's a caveat — you do have to tell if your diagnosis interferes with performing your basic duties.

Deciding whether to tell — and who to tell — is an intensely personal decision each of us must make for ourselves. Some might consider it essential to disclose their diagnosis because they hold managerial positions or run their own business. Others consider that a reason not to tell; privacy and protection may be of the utmost concern.

Most likely, your employer, co-workers and/or employees all depend on you not just to be there, but also to be there. They rely on your organizational skills, your ability to think quickly and creatively on your feet, to make the right decisions on the fly, and your endless energy.

The bottom line is that any changes in your productivity level, appearance and/or any extended absences will give people cause for concern — but whether they're concerned about your health or your ability as a worker may depend on how you handle delivering the news.