Websites that market personalized cancer care services often overemphasize benefits and downplay limitations. In addition, many sites offer genetic tests whose value for guiding cancer treatment has not been shown to be clinically useful.
According to a study reported by HMS researchers in the May issue of the Journal of the National Cancer Institute, the unregulated nature of online marketing of cancer-related genetic tests contributes to an unbalanced representation of the tests’ benefits and limitations.
In their analysis of fifty-five websites offering these services, says first author Stacy Gray, “we found a lot of variation.” In addition, 88 percent of the websites offered one or more nonstandard test that lacked evidence of clinical utility in routine oncology practice.
Gray, an HMS assistant professor of medicine at Dana-Farber Cancer Institute and an investigator in the Dana-Farber Center for Outcomes and Policy Research, was part of a team that included Katherine Janeway ’00, an HMS assistant professor of pediatrics at Dana-Farber.
The investigators analyzed precision, or personalized, cancer medicine products and services marketed by such entities as private companies, academic medical centers, physicians, and research institutes.
Precision cancer medicine often refers to the testing of DNA from 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, in their selection of a therapeutic agent targeted to the particular mutations found. Such targeted agents may be more effective and cause fewer adverse effects than those used in standard chemotherapy.
More than 50 percent of the websites reviewed offered somatic testing, which is the genetic characterization of the tumor itself, while 20 percent marketed germline testing, which analyzes the patient’s genome. Germline testing may identify altered genes that could indicate the risk of developing cancer. In addition, 44 percent of sites offered some form of personalized cancer care, with some claiming that their products led to treatments that increased life expectancies and others indicating that their analyses of tumors could identify effective treatments for a given cancer.
Claims and information posted on Internet sites are not regulated by agencies such as the U.S. Food and Drug Administration. The FDA recently indicated, however, that it intends to begin regulating genomic testing more broadly.