CISN - Molecular Diagnostics

Molecular Diagnostics

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Introduction

"Molecular diagnostics” is another term that you may never have heard of before your cancer diagnosis. Since it's difficult to discuss personalized medicine without talking about molecular diagnostics, we have an entire section on the topic. We will therefore discuss the meaning of ”molecular diagnostics” and how it may affect your treatment choices.

Simply put, molecular diagnostics includes all tests and methods used to identify a disease or the likelihood of developing a specific disease by analyzing biomarkers (DNA, RNA, or proteins).

Once particular biomarkers are identified using a molecular diagnostic, your doctor could learn important information about the biology of your cancer, helping him determine treatment decisions specific to your case.

Right now biomarkers that can be matched to targeted treatments have not yet been identified and validated for all cancer types. But, research is ongoing to detect such markers and to introduce additional successful targeted therapies for different cancers.

Molecular diagnostics techniques may include the following:

Stand-alone genetic tests
Biomarker tests
Companion diagnostics1

We will discuss each of the items listed above to provide you with a better understanding of their purpose.

Select patients for targeted therapies based on their molecular profiles.
Modify the dose of a drug so that it matches each patients needs.
Assess early response to therapy and/or to monitor patients during treatment.
Identify an individual's risk of developing adverse drug reactions.
Guide treatment decisions.2

For example, patients with malignant melanoma and metastatic lung, breast, or brain cancers are now routinely being offered a ”molecular diagnosis” in some clinical centers, enabling their doctors to select targeted treatments.

Malignant melanoma is no longer viewed as one disease, but instead can be classified by its genetics; a gene called BRAF has been found to be mutated in approximately 70 % of cases.
Non-small-cell lung cancer (NSCLC) may be associated with mutations in a number of genes, including the epidermal growth factor receptor (EGFR) gene, the KRAS gene, as well as rearrangements of the ALK (anaplastic lymphoma kinase) gene.

“Content Developed September 1, 2012”