Genetic mutations play a big role in how cancer develops. They help create tumors through different ways:

1. Types of Mutations:

   • Point mutations: These changes can swap one building block in a protein, which might turn on cancer genes. For example, about 30% of cancers have changes in the TP53 gene.
   • Insertions/Deletions: These mutations can mess up how a gene works. A common example is the KRAS gene, which is found to be mutated in around 25% of colorectal cancers.
   • Copy number variations: This involves having extra or missing copies of certain genes. It can affect cancer genes and those that normally stop cancer growth, impacting how cells grow.

2. Pathway Implications:

   • Mutations can occur in important pathways (like p53, Rb, and PI3K) that control how cells grow and die.
   • Around 60% of tumors have mutations in key genes that cause cells to grow without stopping.

3. Statistics:

   • Over 90% of cancers show changes in their DNA that are not inherited. About 5-10% have inherited mutations that make a person more likely to get cancer.

These genetic changes together make cancer worse by allowing cells to keep growing, ignore signals to stop growing, and spread to other parts of the body.