If you are an adoptee or someone with unknown close biological family members, I always recommend gathering health history and sharing with your physician. You need to identify who they are, but that's possible with the availability of commercial DNA testing services.
If you are concerned or not interested in contacting biological family, there are other options available. Easily accessed information about their death or health issues may seem unrealistic, but it's not. You would be surprised at what you will find on social media, newspaper archives, or a simple Google search.
Also, you can generally request a death certificate from the state or county where the death occurred. Recently, I did just that for Alice, a 60-year-old adoptee with a history of ovarian cancer. Genetic testing at the time did not reveal any known mutations. After discovering her maternal grandmother died at 43 years old, I raised the red flag. I 'm sharing a copy of the certificate here, more proof this information is critical.
Alice's grandmother died at 43, a red flag and something I thought needed to be researched.
Here is the actual certificate with cause of death.