Sorry CC the PMI (insurer) is interested in pre existing disease and the risk of recurrence. The AME is interested in sudden incapacitation and death. The PMI may well give you a discount for a failed medical!!!! The AME may pass you for having had the operation to treat the condition. Opposite corners.
There are no rules but I see no reason for HR to see the information. They cant modify the underwriting or the premium and will need to demonstrate additional levels of staff training and security to handle the information. And if some 16 year old intern blabbers stand by for a big pay out. If it were my company I would keep HR out of it, and that is the norm many of my patients tell me about.