Web sites that market personalized cancer care services often overemphasize their purported benefits and downplay their limitations, and many sites offer genetic tests whose value for guiding cancer treatment has not been shown to be clinically useful, according to a new study published in the Journal of the National Cancer Institute (2015; doi:10.1093/jnci/djv030).
Internet marketing of cancer-related gene tests is unregulated. Therefore, there is wide variation in how these services are presented, posing a challenge for consumers and their physicians, reported researchers from Dana-Farber Cancer Institute in Boston, Massachusetts.
“We wanted to see if consumers are getting a balanced picture of benefits and limitations of these services,” said Stacy Gray, MD, AM, first author of the report analyzing 55 web sites marketing the services. “We found a lot of variation. Some of the information is good, but all of it needs to be looked at critically by consumers and health care providers.”
The study found that “in general, the benefits of these personalized cancer products are reported much more frequently than are the limitations,” said Gray. In addition, 88% of the web sites offered one or more nonstandard tests that lacked evidence of clear clinical utility in routine oncology practice.
The investigators analyzed personalized or precision cancer medicine (PCM) products and services marketed by private companies, academic medical centers, physicians, research institutes, and other organizations.
Precision cancer medicine was defined by the authors as “… products or services that could be used to tailor, personalize, or individualize care based on genomic or tumor-derived data.”
PCM often refers to testing DNA from samples of a patient’s tumor to detect mutations or other genetic abnormalities that may help physicians predict how the disease will behave, and, in a limited but growing number of cases, select a drug or drugs targeted to the particular mutations found in the cancer. Such targeted agents may be more effective and cause fewer adverse side effects than standard chemotherapy.
These tests are termed somatic because they look at the genetic characteristic of the tumor itself. Another type of PCM testing, called germline, analyzes the patient’s personal genome, which is a panel or set of inherited genes and other DNA, and may turn up altered genes in a healthy person that raise his or her risk of developing cancer.
A majority of the Internet sites (58%) offered somatic testing, and 20% marketed germline testing. In addition, 44% of sites offered some form of personalized cancer care.
The report cited examples of marketing claims. Claims and other information posted on Internet sites are not subject to regulation by agencies such as the Food and Drug Administration (FDA) or the Federal Trade Commission (FTC).
More recently, the FDA has said it intends to begin regulating genomic testing more broadly. The researchers stated that patients will continue to need guidance from oncology providers to navigate decisions about personalized cancer medicine.