Mismatch Repair Panel by Immunohistochemistry
Ordering Recommendation
First-line screening test for Lynch syndrome.
New York DOH Approval Status
Specimen Required
Tumor tissue.
Formalin fix (10 percent neutral buffered formalin is preferred) and paraffin embed specimen. If sending precut slides, do not oven bake. Transport tissue block or 10 unstained (3-5 micron thick sections), positively charged slides in a tissue transport kit (ARUP supply #47808) available online through eSupply using ARUP Connect(TM) or contact ARUP Client Services at 800-522-2787. (Min: 5 slides). Protect paraffin block and/or slides from excessive heat.
Room temperature or refrigerated. Ship in cooled container during summer months.
Frozen specimens. Specimens fixed or processed in alternative fixatives (alcohol, Prefer) or heavy metal fixatives (B-4 or B-5). Depleted or no tumor in tissue. Specimens submitted with nonrepresentative tissue type. Decalcified specimens.
Only tissue that is clearly carcinoma (established by histological criteria) should be tested. 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. If multiple specimens (blocks or slides) are sent to ARUP, they must be accompanied by one of the following: an order comment indicating that the ARUP pathologist should choose the specimen most appropriate for testing (e.g., "Choose best block"), or individual orders for each sample submitted. A Pathologist Block Selection Fee (ARUP test code 3002076) will be added to orders that utilize the first option. If multiple specimens are sent to ARUP without a request for pathologist block/slide selection or individual orders, they will be held until clarification is provided.
Ambient: Indefinitely; Refrigerated: Indefinitely; Frozen: Unacceptable
Methodology
Qualitative Immunohistochemistry
Performed
Mon-Fri
Reported
1-3 days
Reference Interval
Interpretive Data
Laboratory Developed Test (LDT)
Note
This orderable is offered as a panel only. Individual MLH1, MSH2, MSH6, and PMS2 IHC stains are not offered at this time.
This orderable is performed as a stain and return (technical) service only. Please refer to ARUP test code 0049302 if ARUP pathologist interpretation is needed.
Hotline History
Hotline History
CPT Codes
88342/88341x3
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
3017883 | SO MSI Panel by IHC | |
3017884 | SO MSI Reference Number |
Aliases
- MLH1 IHC
- MMR IHC
- MMR Immunostaining
- MSH2 IHC
- MSH6 IHC
- MSI
- MSI Antibody Immunostaining
- MSI IHC
- PMS2 IHC