A proteomic test designed to detect ovarian cancer at its earliest stages has raised concerns about the best way to regulate the efficacy and proper use of the latest high-throughput diagnostic technologies.

OvaCheck, which uses mass-spectrometry analysis of blood samples to identify patients with ovarian cancer, is based on a study by Petrocoin et al. (The Lancet, 16 February 2002). At issue is the marketing by one of the companies licensed to conduct the test before its validation and approval by the US Food and Drug Administration (FDA). “The results have not been reproduced, and the test needs to be controlled for potentially confounding factors ...” said Eleftherios P. Diamandis, University of Toronto (Wagner, L., JNCI Cancer Spectrum, 7 April 2004).

It is not clear, however, which government agency should regulate these new diagnostics, as the FDA has never before evaluated a multiplex test in which more than one protein is used as a marker. According to FDA official Steven Gutman, it is not clear if the test is “subject to regulation by [the Centers for Medicare and Medicaid Services], under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), or whether it may also require premarket review by the FDA” (Wagner, L., JNCI Cancer Spectrum, 7 April 2004).

The US government will need to quickly find a balance between the interests of patients, who want access to the latest diagnostics, and the careful regulation of these assays, as more become available. A gene-expression-profile test called OncotypeDX, developed by a company called Genomic Health to identify women who are likely to undergo breast cancer recurrence, has already appeared on the market with CLIA approval, but without FDA review.