However, if the insured person lied on the life insurance application about not having cancer when he or she actually did, and was approved for life insurance coverage and got insured while having cancer, the life insurance company has the right to deny payment of any claim within the first two years of the policy being "In Force".
This is called "misrepresentation of a material fact" about your health which may have caused the insurer to deny you coverage for life insurance had the insurer known about your health problem.
Learn more about Does life insurance cover cancer?