Pathwork Tissue Of Origin Test Shows Potential To Aid Cancer Diagnosis
Pathwork Diagnostics, a molecular diagnostics company focused on oncology, will present three studies involving the gene expression based Pathwork Tissue of Origin Test at the Association for Molecular Pathology (AMP) Annual Meeting.
In a poster entitled, "Gene Expression Microarray-Based Diagnostic Test May Identify Primary Tumor Site in Patients with Carcinoma of Unknown Primary (CUP)," Fabiola Medeiros, MD, Assistant Professor of Laboratory Medicine and Pathology at the Mayo Clinic, found that the Pathwork Tissue of Origin Test indicated a probable origin of metastatic CUP in 73 percent of the tumors tested.
CUP cases account for approximately three percent of all malignancies, representing one of the 10 most frequent cancer diagnoses. The CUP samples from the Mayo Clinic consisted of 11 fresh-frozen tumor specimens, whose origin could not be determined after full clinical and imaging workup, including immunohistochemistry. The cases where the tissue of origin was identified have treatment options that show increased survival compared to standard therapies used for the treatment of CUP.
"Identifying the tumor's origin can allow oncologists to prescribe more appropriate, targeted therapy and avoid the toxicity of less-specific chemotherapies. They may also be able to enroll these patients in new therapeutic clinical trials which otherwise would not be available without a defined tissue of origin," said David Henner, MD, PhD, Chief Medical Officer of Pathwork Diagnostics.
Since the test was validated and FDA-cleared using metastatic tumors for which the primary site was known, the purpose of this study was to examine the diagnostic performance of this test using CUP specimens. Analysis of the accuracy of these results is limited, since there is no reference diagnosis for comparison with CUP specimens where by definition the primary site is unknown. The test uses a microarray to measure the expression pattern, comprising more than 1,500 genes, in the tumor and compares it to the expression patterns of a panel of 15 known tumor types, representing 60 morphologies overall, to help determine the tumor's origin.