Informed consent

Typically, the healthcare provider ordering the test would be your oncologist. However, in some institutions your oncologist may refer you to a geneticist who will order the test.

Prior to collecting a sample for genetic testing, the ordering healthcare provider will ask you to sign a document that gives patient consent to perform the test known as informed consent. This document states that the test is voluntary and that the patient or patient’s parent if the child is under 18 fully understands and agrees to the test. Your healthcare provider should discuss the risks, benefits, and limitations of the test prior to signing the consent form.

Turnaround time for results

Turnaround time for results depend on the laboratory where the test is performed. Typically, single gene testing can take up to a week for results, whereas most current NGS assays take 2 to 4 weeks for results.

Tissue banking

You may elect to store the cancer tissue of your child for the purpose of basic science and clinical research. Tissue banks are repositories that collect and store biological samples and associated clinical data. Importantly, some clinical trials require that your child’s tumor tissue be collected and stored in a central biobank. You will also be asked to sign a consent to allow a local or remote biobank to collect and store your child’s sample. The name of your child will remain undisclosed.

Interpreting the results

The ordering provider/oncologist should deliver and explain the results of the genetic testing. It is important to know that the results of genetic testing are not always straightforward, especially sequencing-based methods. For example, the sequence of a gene of interest may reveal a change from the normal sequence, but it does not necessarily mean that the change (often termed variant) causes a change in the function of the gene resulting in cancer.

In addition, when performing WES or WGS, unexpected secondary findings for which the test was not initially indicated may be found. For example, a WES test may reveal a change in a gene that causes heart disease. A thorough discussion with your oncologist prior to undergoing the test should include any potential secondary results, their significance and future actions that would need to be taken.