In some cases, a mutation that predisposes to cancer is passed down in the family, causing the person carrying the mutation to have an increased risk of cancer (see Inherited Cancer Susceptibility). Cancer types like breast, ovary, colon, pancreas, and prostate are among inherited cancers, and cases with a family history should be evaluated with genetic counseling.
In some cases, mutations in genes that control cell growth and division can cause a healthy cell to turn into a tumor cell. Cancer often occurs as a result of the lifetime accumulation of multiple mutations. Environmental factors, lifestyle, ultraviolet rays, hormones, and viruses may play a role in cancer development.
Mutations are specific to the person; they can be seen in different genes, numbers, and types. The characteristic of each tumor is unique, so cancer treatment should be personalized.
Testing can provide information about the tumor’s genetic characteristics, treatment options, and response to treatment. Genetic diagnosis provides information specifically for targeted therapy applications, also known as personalized medicine.
What does genetic testing do in cancer cases?
Specifies the most appropriate treatment option for the person
Helps identify the underlying cause in cases where there is no response to treatment and plan alternative treatments
Predicts response to treatment and course of the disease
Helps specify personalized clinical trial options
How is genetic testing done in cancer cases?
The tissue obtained from a biopsy or operation contains tumor cells. These cells are separated from healthy cells in the laboratory, and the properties of DNA, RNA, or proteins belonging to the tumor are tested. In cases where a biopsy cannot be performed, blood can also be used to obtain tumor cells. This application is called Liquid Biopsy, and it can be used alongside tissue biopsy in certain cases or as an alternative in cases where a biopsy cannot be performed.
Who should have genetic testing?
Genetic testing is routinely performed for cancer types such as breast, ovarian, non-small cell lung and colon, and melanoma. In some cases, genetic testing may be recommended for advanced cancers that do not respond to treatment or that recur despite treatment. Consult your doctor for information about whether genetic testing is suitable for you and the benefits it can provide.
