How can i overcome this hypochondria about cancer?

Seek advice: There is no easy answer. What is your underlying fear? Are there other "phobias" or mental health conditions? You might visit your primary care provider. You might need to seek counselling.

Hypochondria: Cognitive Behavioral Therapy is often the most effective approach to treating hypochondria. Psychoeducation and exposure therapy have been used as well as treatment with antidepressant medications when warranted.