I understand exactly how you feel. My Father and his 5 siblings died of cancer. My oldest sister had cancer but died of a heart problem. My middle sister just died in April of Ovarian Cancer. I have a long family history of cancer and I had 4 skin cancers removed last year. Yes, I have fears too but I have learned not to dwell on what may be ahead for myself. I just take it one day at a time. I do have my moments however and then I have to pull back to staying in the moment.
It is normal to experience some fear. Telling yourself not to worry or criticizing yourself for being afraid won't make these feelings go away. Accept that you are going to experience some fear and focus on finding ways to help yourself manage the anxiety is the best advice I can give you.
It may also help to remember that the fear usually lessens over time, and that you won't always feel so anxious.
Talking about your fears and feelings or writing down your thoughts in a journal can help reduce your anxiety. Talking and thinking about your concerns can help you explore the issues underlying your fear.
For me, I chose therapy and it helped me a great deal.
Please do feel comfortable continuing to post your fears and anxieties here in your own thread. We are here to support you and please know we care.
Wishing you the best,