Step 1. Buy firecracker.
Step 2. Buy cute baby.
Step 3. Distract cancer by exploding the firecracker.
Step 4. Throw baby at cancer.
Step 5. Instruct baby to destroy cancer.
Step 6. Return baby. Full refund if within thirty days.
Step 7. Break for lunch.
(NB: Do not attempt to return firecracker. Does not work on all cancers, just the distractable ones.)