Molecular diagnostics more important, still underutilized

Cancer care is becoming increasingly personalized. In one cancer after another, science is yielding discoveries about genetic mutations that affect survival and treatment outcomes. These discoveries are both prognostic, indicating tumor aggressiveness, and predictive, forecasting treatment efficacy.

These discoveries have led to better survival and smarter treatment in some once-hopeless diagnoses. A decade ago, 80 percent of patients with metastatic melanoma lived less than one year after diagnosis. Today, the one-year survival rate is 60 percent, thanks to the discovery of the BRAF mutation and therapies that target it. Similarly, lung cancer is no longer a one-size-fits-all diagnosis; 60 percent of non–small-cell lung cancers have a known genetic driver that guides treatment selection. Lung cancers in nonsmokers often respond well to targeted therapies, but those in smokers tend to have a different molecular makeup and rarely respond to any treatment regimen.

National Comprehensive Cancer Network guidelines include more than 600 molecular tests to guide treatment selection, yet an NCCN survey shows that molecular testing isn’t yet standard practice in oncology. Nearly 3 in 10 oncologists rarely or never perform molecular testing when prescribing targeted therapies.

Among clinicians who do order molecular diagnostic tests, the reasons are varied. Respondents to a separate NCCN survey said that the most frequent reasons for ordering a test were the evidence supporting its use and its specific use. Only 35 percent placed importance on a payer requirement that a test be performed before a targeted agent is prescribed. — Michael D. Dalzell

What information is important to clinicians about molecular tests?


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