Genetic Insights into Cancer: Understanding the Role of Genetics in Cancer Development

Are All Cancers Genetic (Hereditary) in Nature?

Not all the cancers caused are hereditary in nature. Hereditary cancers are the one which runs in families and these include spectrum of cancers. For example breast cancers and ovarian cancers run together and this syndrome is called as hereditary breast ovarian cancer syndrome (HBOC). There is high risk of hereditary cancers when the cancers occur in individuals who are young age. Therefore it is important to know about the detailed family history of cancers and any other medical illness on both paternal and maternal family members as hereditary cancers can be from both the parents.

Is genetic testing done in all cancers?

Simple and direct answer to this question is NO.  Genetic testing is not done in all cancers. There are specific indications for genetic testing in cancer. Before going into further details one should know that genetic testing is basically two types in cancers. First is the somatic testing and second is the germline testing. Somatic genetic testing is done on the cancer tissue specimen and it will let us know about the mutations which had occurred in that specific cancer, these mutations can be either inherited or acquired. Second genetic testing is germline genetic testing, it tests whether there are any inherited genetic mutations in the cancer. These are the mutations which can run in families.

When to get genetic testing done?

Somatic testing or germline genetic testing is done based on the age, type of cancer, detailed family history and therapeutic implications of the cancer type. As already discussed there is no need for the genetic in all cancers.

How does genetic testing guide the management of cancers?

Depending on the somatic and germ line mutations identified it can help in the cancer treatment and screening of the cancers. For example, if a ovarian cancer patient with the family history of breast cancer had BRCA 1 germline mutation then she is eligible for the treatment with PARP inhibitors (targeted therapy) which has high impact on disease progression and survival. And then the family members of the patient are eligible for genetic testing and they should be screened for specific cancers for early detection and management which could be worse if not detected early.