ARUP's Laboratory Test Directory

Mismatch Repair by Immunohistochemistry with Reflex to BRAF Codon 600 Mutation and MLH1 Promoter Methylation : 2002327
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Additional Technical Information
  


Mnemonic: MSI REFLEX

Ordering Recommendation: Distinguish between sporadic and Lynch-associated microsatellite unstable (MSI) colorectal cancer.
Methodology: Qualitative Immunohistochemistry/Qualitative Real-time Polymerase Chain Reaction
Performed: Mon, Thu
Reported: Within 5 days. Within 15 days if reflexed.
Specimen Required: Collect: Tumor tissue.

Specimen Preparation: Formalin fix (10 percent neutral buffered formalin is preferred) and paraffin embed tissue. If sending precut slides, do not oven bake. Transport tissue block or 20 unstained (3-5 micron thick sections), positively charged slides in a tissue transport kit (ARUP supply #47808). Available online through eSupply using ARUP ConnectTM or contact ARUP Client Services at (800) 522-2787. (Min: 15 slides). Protect paraffin block and/or slides from excessive heat.

Storage/Transport Temperature: Room temperature or refrigerated. Ship in cooled container during summer months.

Remarks: Include surgical pathology report. Submit electronic request. If you do not have electronic ordering capability, use an ARUP requisition form complete with an ARUP client number. For additional technical details, please contact ARUP Client Services at (800) 522-2787..

Unacceptable Conditions: Less than 25 percent tumor. Specimens fixed/processed in alternative fixatives (alcohol, Prefer®). Decalcified specimens.

Stability (collection to initiation of testing): Ambient: Indefinitely; Refrigerated: Indefinitely; Frozen: Unacceptable
Interpretive Data: Refer to report.

Refer to the Colorectal Cancer or Lynch Syndrome topic at arupconsult.com.

See Compliance Statement B: www.aruplab.com/CS
Note: If MLH1 is abnormal for Mismatch Repair by IHC, then BRAF codon 600 will added. If BRAF codon 600 is negative, MLH1 Promoter Methylation will be added. Additional charges apply.
CPT Code(s): 88342 (4); if reflexed, add 88381, 81210, G0452; if further reflexed, add  81479
Cross References: HNPCC/Lynch Syndrome (Mismatch Repair by Immunohistochemistry with Reflex to BRAF Codon 600 Mutation and MLH1 Promoter Methylation) , Lynch Syndrome (Mismatch Repair by Immunohistochemistry with Reflex to BRAF Codon 600 Mutation and MLH1 Promoter Methylation) , MSI (Mismatch Repair by Immunohistochemistry with Reflex to BRAF Codon 600 Mutation and MLH1 Promoter Methylation)