Genetic Tests for Targeted Cancer Therapy

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.What are genetic tests for targeted cancer therapy?
Genetic tests for targeted cancer therapy detect mutations (changes) in the DNA of cancer cells. Knowing whether the cancer has a particular mutation can help guide the type of treatment that a person receives. The presence or absence of certain mutations can predict who may benefit from certain drugs and who is not likely to respond.
Cancer is the uncontrolled growth of abnormal cells. Multiple factors may contribute to this uncontrolled growth. One such factor is the malfunctioning of proteins involved in controlling cell growth and maturation. The proteins usually malfunction as a result of a mutation in the DNA of the gene that codes for that protein. Some mutations may result in a defective protein that cannot stop cell growth while other mutations may produce a protein with altered function that stimulates cell growth. The net result is unchecked growth and division of these abnormal cells (cancer).
Medical researchers have long studied these changes in genes in order to better understand cancer and to develop drugs to fight it. Their goal has been to create drugs that disrupt a specific step in cancer growth, while doing minimal damage to normal cells. These are called targeted drugs or targeted therapy. What researchers have noted is that specific types of cancer are frequently associated with specific genetic mutations. Not every cancer will have them, but a significant percentage will, and cancers with these mutations usually have a more predictable response to certain drug treatments compared to cancers without these mutations.
These findings have led to two important developments:
- Cancer drugs that inhibit or target very specific proteins associated with certain cancers (Two examples are tyrosine kinase inhibitors and epidermal growth factor receptor (EGFR) antibodies.)
- Genetic tests to detect the presence of mutations in cancer tissue that tell a healthcare practitioner whether the person being tested is likely to benefit from a specific therapy
Medical researchers continue to explore the genetics of cancer and to look for opportunities to develop new therapies. Additionally, some cancers eventually stop responding to certain therapies and develop resistance to that therapy. Genetic research may offer insights into how resistance to therapy occurs.
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Tests: EGFR Mutation Testing, Her-2/neu, Estrogen/Progesterone Receptor Status, BCR-ABL, BRCA Mutation Testing, JAK2 Mutation, KRAS Mutation, Liquid Biopsy, PD-L1
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Association for Molecular Pathology
American Cancer Society: Targeted Cancer Therapy
National Cancer Institute: Targeted Cancer Therapies
American Cancer Society: Lung Cancer (Non-Small Cell)
National Cancer Institute: General Information About Non-Small Cell Lung Cancer (NSCLC)
American Cancer Society: Gastrointestinal Stromal Tumor (GIST)
National Cancer Institute: Colorectal Cancer
American Cancer Society: Colorectal Cancer Prevention and Early Detection
MD Anderson Cancer Center: Personalized Cancer Therapy
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