Why do most cancers require the mutation of multiple genes?

Sanders 3rd Edition
Ch. 14 - Analysis of Gene Function via Forward Genetics and Reverse Genetics
Problem C.2cA tumor is a growing mass of abnormal cells. What must happen for a benign tumor to become malignant?
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Key Concepts
Benign vs. Malignant Tumors
Genetic Mutations and Cellular Transformation
Metastasis and Invasion Mechanisms
A tumor is a growing mass of abnormal cells. Describe the difference between a benign tumor and a malignant tumor.
A tumor is a growing mass of abnormal cells. Give an example from this chapter of a benign tumor that becomes a malignant tumor.
Genetic counseling has not been discussed in this chapter, but it is a service provided by trained professional counselors who also have detailed knowledge of medical genetics, as described in Application Chapter A. Genetic counselors provide details about gene mutations and have knowledge of most of the details of diseases associated with genetic abnormalities. With regard to genetic testing to identify one's personal risk of cancer, what are the three or four topics you think are most important to be able to discuss with a genetic counselor?
Radiation is frequently used as part of the treatment of cancer. The radiation works by damaging DNA and components of the cell. How can radiation treatment control or cure cancer?
Radiation is frequently used as part of the treatment of cancer. The radiation works by damaging DNA and components of the cell. Is there a risk of damage to noncancer cells?