Patient Confidentiality?
I'm afraid there is no excuse for "patient confidentiality". You're either Fit or Unfit to fly, doesn't matter what the inherent condition is. If a Dr suspected a Pilot of having a terminal illness, the pilot is immediately grounded. That Dr has a duty to report to the employer/authorities that the pilot is Unfit to fly, the issue remaining confidential. Because if the pilot doesn't declare himself unfit they continue flying...