Test Code NF2 Merlin (NF2) Immunostain, Technical Component Only
Ordering Guidance
This test includes only technical performance of the stain (no pathologist interpretation is performed). If diagnostic consultation by a pathologist is required order PATHC / Pathology Consultation.
Shipping Instructions
Attach the green "Attention Pathology" address label (T498) and the pink Immunostain Technical Only label included in the kit to the outside of the transport container.
Specimen Required
Specimen Type: Tissue
Supplies: Immunostain Technical Only Envelope (T693)
Container/Tube: Immunostain Technical Only Envelope
Submit:
-Formalin-fixed, paraffin-embedded tissue block
OR
-2 Unstained, positively charged glass slides (25- x 75- x 1-mm) per test ordered; sections 4-microns thick
Secondary ID
622010Useful For
The distinction of reactive mesothelial proliferation from mesothelioma
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
IHTOI | IHC Initial, Tech Only | No | No |
IHTOA | IHC Additional, Tech Only | No | No |
Testing Algorithm
For the initial technical component only immunohistochemical (IHC) stain performed, the appropriate bill-only test ID will be reflexed and charged (IHTOI). For each additional technical component only IHC stain performed, an additional bill-only test ID will be reflexed and charged (IHTOA).
Method Name
Immunohistochemistry (IHC)
Reporting Name
Merlin (NF2) IHC, Tech OnlySpecimen Type
TECHONLYSpecimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
TECHONLY | Ambient (preferred) | |
Refrigerated |
Reject Due To
Wet/frozen tissue Cytology smears Nonformalin fixed tissue Nonparaffin embedded tissue Noncharged slides ProbeOn slides Snowcoat slides |
Reject |
Clinical Information
This assay is intended to identify the presence of Merlin (moesin, ezrin, and radixin-like protein) expression within the membrane or cytoplasm of tumor cells. Merlin is the NF2 gene product displaying striking similarity to ezrin, radixin, and moesin proteins. It can be difficult to distinguish reactive mesothelial proliferation from mesothelioma. Loss of NF2 expression is specific for malignant processes and based on studies has been shown to add sensitivity to existing mesothelioma immunohistochemistry markers.
Interpretation
This test does not include pathologist interpretation, only technical performance of the stain. If interpretation is required, order PATHC / Pathology Consultation for a full diagnostic evaluation or second opinion of the case.
The positive and negative controls are verified as showing appropriate immunoreactivity. If a control tissue is not included on the slide, a scanned image of the relevant quality control tissue is available upon request; call 855-516-8404.
Interpretation of this test should be performed in the context of the patient's clinical history and other diagnostic tests by a qualified pathologist.
Method Description
Immunohistochemistry on sections of paraffin-embedded tissue.(Unpublished Mayo method)
Day(s) Performed
Monday through Friday
Performing Laboratory

Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
88342-TC, Primary
88341-TC, If additional IHC
LOINC Code Information
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
622011 | Merlin (NF2) IHC, Tech Only | No LOINC Needed |