Some cancers are caused by specific changes in genes. Genes carry instructions for proteins in cells and an abnormal change to the genes can lead to an alteration of the proteins, which can cause uncontrolled cell growth and formation of a cancerous tumor.
One type of genetically-driven cancer is called tropomyosin receptor kinase (TRK) fusion cancer.
Neurotrophic tyrosine receptor kinase (NTRK) genes provide instructions for TRK proteins. When an NTRK gene joins or “fuses” with an unrelated gene, it starts to produce an altered TRK fusion protein. This TRK fusion protein becomes active and causes a cancerous tumor to grow.
TRK fusion cancer is a very unique and rare disease and is defined by this specific gene alteration. The cancer is not related to a certain type of tissue or the age of the patient; it can occur anywhere in the body, in both children and in adults.
Only specific genomic tests can detect NTRK gene fusions, the underlying cause of TRK fusion cancer. By testing patients and finding out what is driving their cancer, doctors could target the root of the disease. It is important that high-quality genomic testing that looks for actionable targets becomes part of routine clinical practice so patients have the chance to benefit from therapies that selectively inhibit the oncogenic driver that causes their cancer.
With emerging research on TRK fusion cancer, we are one step closer to precision medicine, where tumor genetics, rather than where the tumor is in the body, help doctors select specific treatment approaches that could more likely benefit their patients.
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