Pathwork Diagnostics Inc, a molecular diagnostics company focused on oncology, announces that the Journal of Clinical Oncology (JCO) has published the results of the Pathwork® Tissue of Origin Test validation study in a paper entitled, “Multicenter Validation of a 1,550-Gene Expression Profile for Identification of Tumor Tissue of Origin.”
The results of the 547-specimen study showed that the test has significant potential to reduce diagnostic uncertainty for poorly differentiated, undifferentiated, or metastatic tumors. To date, no other tests in this category have undergone as large a clinical validation study or produced such strong results.
“This study, which is the first of many clinical studies being performed, clearly demonstrates the exceptional performance and robust science underlying our test,” said Deborah J. Neff, President and Chief Executive Officer of Pathwork Diagnostics. “We believe the Tissue of Origin Test can benefit physicians by allowing them to diagnose tumors with uncertain origins with greater confidence because the test provides objective data and the ability to both rule in and rule out tumor types.”
To determine the tumor’s origin, the Pathwork Tissue of Origin Test uses microarray technology to measure the gene expression pattern, comprising more than 1,500 genes, in a tumor with an uncertain origin and compare it to expression patterns of a panel of 15 known tumor types, representing 90% of all solid tumors and 58 morphologies overall.
In the multicenter, blinded clinical validation study, which was used as the basis for the test’s FDA clearance in July 2008, the test examined 547 frozen tumor specimens from patients diagnosed with one of the tumor types in the panel, all of which were either metastatic, poorly differentiated, or undifferentiated. The test demonstrated 88% positive percent agreement (akin to sensitivity) and greater than 99% negative percent agreement (akin to specificity) with available diagnoses.
Although the JCO paper only reported results for frozen tissue samples, a separate validation study performed by Pathwork with FFPE (formalin-fixed, paraffin-embedded) specimens showed similar performance. Both the frozen and FFPE versions of the test are commercially available as a service through Pathwork Diagnostics Laboratory.
The paper published in the American Society of Clinical Oncology’s journal was authored by Federico Monzon, MD, Director of Molecular Diagnostics at The Methodist Hospital in Houston, Tex. Dr Monzon’s results showed that the test should become a valuable complement to currently available diagnostic methods for tumors with uncertain origins.
The abstract can be read online and the full paper is available for download on the company’s Web site.
Source: Pathwork
