he Tissue of Origin test is a microarray-based gene expression test that aids in identifying challenging tumors, including metastatic, poorly differentiated, and undifferentiated cancers. A study of 284 clinical samples with Tissue of Origin Test results were categorized according to the clinician’s pretest diagnosis, using ICD-9 codes and the biopsy site. The test predicted either a change from nonspecific to a specific site or a change from one primary site to another in 81% of cases. For 15% of cases, the Tissue of Origin Test confirmed the submitted diagnosis. Overall, based on test prediction and the NCCN guidelines, first-line chemotherapy treatment would change for 63% of the cases.
The Tissue of Origin test is a microarray-based gene expression test that aids in identifying challenging tumors, including metastatic, poorly differentiated, and undifferentiated cancers. Pathwork (now defunct) had evaluated the Tissue of Origin test in studies involving more than 1,100 patient specimens and had published two large validation studies in the Journal of Clinical Oncology and the Journal of Molecular Diagnostics. Medicare issued a positive coverage decision for the Tissue of Origin test in 2011. The National Comprehensive Cancer Network clinical practice guidelines on occult primary or cancer of unknown primary (version 2.2017) notes that outcomes data is not currently available that recommends the routine use of molecular profiling in the workup of occult primary tumors..
Dumar, E. I., Lyons-Weiler, M., Sciulli, C., Garrett, C. T., Schrijver, I., Holley, T. K., et al. (2008). Interlaboratory performance of a microarray-based gene expression test to determine tissue of origin in poorly differentiated and undifferentiated cancers. Journal of Molecular Diagnostics, 10 (1), 67-77. sponsored)
Kerr, S. E., Schnabel, C. A., Sullivan, P. S., Zhang, Y., Singh, V., Carey, B., et al. (2012) Multisite validation study to determine performance characteristics of a 92-gene molecular cancer classifier. Clinical Cancer Research, 18 (14), 3952-3960.
Monzon, F. A., Medeiros, F., Lyons-Weiler, M., & Henner, W. D. (2010). Identification of tissue of origin in carcinoma of unknown primary with a microarray-based gene expression test. Diagnostic Pathology, 5 (3), 1-12.
Proctor, Y., Edmonston, T. B., St. Cyr, B., Jaeger, D., Lass, U., et al. (2011). Accurate classification of metastatic brain tumors using a novel microRNA-based test. The Oncologist, 16 (2), 165-174.
National Comprehensive Cancer Network. (2016, October). NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®). Occult primary (cancer of unknown primary, [CUP]) (V.2.2017).
Kerr SE et al. Multisite Validation Study To Determine Performance Characteristics of a 92-gene Molecular Cancer Classifier. Clin Cancer Res. 2012 May 30.