Molecular testing of colorectal cancer (CRC) is currently the standard of care for guiding the use FDA-approved targeted therapies such as anti-EGFR and anti-PDL1 antibodies. In addition, more investigational clinical actions are often employed for patients with advanced stage CRC including the use FDA-approved drugs for an off-label indication and enrollment in clinical trials. This assay is designed to provide comprehensive molecular results relevant for both standard of care and emerging/investigational clinical actions. This DNA and RNA based, next-generation sequencing test targets 50 genes to detect substitution and insertion/deletion mutations (35 genes), gene amplifications (19 genes), and gene fusions (21 genes). Detectable variants relevant for CRC include, but are not limited to, mutations of KRAS, NRAS, BRAF, PIK3CA, and AKT1; amplification of ERBB2, FGFR1, KRAS, and MYC; and rearrangements of ALK. Importantly, microsatellite instability testing is NOT included in this assay and must be ordered separately if clinically indicated. A complete list of sequenced regions, genes assessed for amplification and detectable fusion transcripts is available below.
Interpretive Report Provided
This test will only detect the mutations within specific gene regions, relatively high-level copy number gains involving specific genes and specific gene fusions (See Additional Information below for specific information). This test may fail to detect low-level copy number gains within evaluated genes (<8) or molecular alterations below the limit of detection of this assay (approximately 5%). Discordant results are rarely observed between metastatic and primary tumors. This test cannot distinguish between somatic and germline alterations. Additional testing may be required if there is concern for a clinically relevant germline alteration. The clinical implications of the findings as indicated in the test report may change based on evolution of the scientific literature.
- AKT1 exons 4 and 7
- PIK3CA exons 2, 5, 7, 8, 10, 14, 19 and 21
- BRAF exons 11 and 15
- NRAS exons 2-4
- KRAS exons 2-4
- CRC Mutation Panel by NGS
- Oncomine genomic profiling
For formalin-fixed, paraffin-embedded tissue, a block containing an area with a high percentage of neoplastic cells (for micro-/macro-dissection) is preferred. Unstained, UNBAKED slides (5-8, 10-micron slides; 10-15 if few neoplastic cells are present) with associated H&E stained slide are also acceptable. Decalcified tissue or other fixatives will be accepted and the assay attempted, however these may result in failed testing due to degraded nucleic acid. Both blocks and slides should be stored at room temperature. A Diff-Quik or Papanicolaou stained aspirate smear (preferable containing a high percentage and overall amount of neoplastic cells) is also acceptable. Store at room temperature.
Previously extracted DNA and RNA may be accepted; however, the extracting laboratory must take responsibility for ensuring that viable, neoplastic cells comprise at least 20% of cellularity within the extracted sample.
Click <a text="here" href="/handbook/Tables/Solid%20Tumor%20Panel%20Mutation%20Regions%20for%20Test%20Directory.pdf"> for list of gene regions sequenced for mutations.
Click <a text="here" href="/handbook/Tables/Solid%20Tumor%20Panel%20Gene%20Fusion%20list%20for%20Test%20Directory.pdf"> for specific gene fusions targeted by the assay.
By ordering this test the clinician acknowledges that informed consent has been obtained from the patient as required by applicable state or federal laws and the ordering clinician has authorization from the patient permitting MLabs to report the test results to the ordering clinician. Test includes microdissection billed as a separate additional charge. Test includes pathologist interpretation of results billed as a separate additional charge. This test is not available without interpretation.