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HelpTest Code LAB4416/1295/MISC ICOS (CD278), Immunostain, Technical Component Only
Additional Codes
Mayo Code: ICOSI
Shipping Instructions
Attach the green pathology address label and the pink Immunostains Technical Only label included in the kit to the outside of the transport container.
Specimen Required
Supplies: Immunostain Technical Only Envelope (T693)
Specimen Type: Tissue
Container/Tube: Immunostains Technical Only Envelope (T693)
Preferred: 2 unstained positively charged glass slide (25 x 75 x 1 mm) per test ordered; sections 4-microns thick.
Acceptable: Formalin-fixed, paraffin-embedded (FFPE) tissue block
Method Name
Immunohistochemistry
Reporting Name
ICOS (CD278) IHC, Tech OnlySpecimen Type
TECHONLYReject Due To
| Wet/frozen tissue Cytology smears Nonformalin fixed tissue Nonparaffin embedded tissue Noncharged slides ProbeOn slides | Reject |
Day(s) and Time(s) Performed
Monday through Friday
Analytic Time
1 dayPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.CPT Code Information
88342-TC, primary
88341-TC, if additional IHC
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| ICOSI | ICOS (CD278) IHC, Tech Only | Order only;no result |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 113596 | ICOS (CD278) IHC, Tech Only | Bill only; no result |
Secondary ID
113518Useful For
Aiding in the classification of T cell lymphomas
Clinical Information
ICOS (CD278) is primarily expressed on activated CD4+ and CD8+ T cells where it regulates immune responses and plays a role in the regulation of T follicular helper cells. ICOS is a sensitive marker for identifying T cell lymphomas of follicular helper T cell origin, especially certain patterns of angioimmunoblastic T-cell lymphoma (AITL) and peripheral T-cell lymphomas with T-follicular helper phenotype (PTCL-TFH). This is becoming increasingly important given WHO 2016 diagnostic guidelines.
Interpretation
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.
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. Contact 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.
Cautions
Age of a cut paraffin section can affect immunoreactivity. Stability thresholds vary widely among published literature and are antigen-dependent. Best practice is for paraffin sections to be cut within 6 weeks.
Clinical Reference
1. Rodriguez-Justo M et al: Angioimmunoblastic T-cell lymphoma with hyperplastic germinal centres: a neoplasia with origin in the outer zone of the germinal centre? Clinicopathological and immunohistochemical study of 10 cases with follicular T-cell markers. Mod Pathol 2009;22(6):753-761
2. Marafioti T, Paterson JC, Ballabio E, et al: The inducible T-cell co-stimulator molecule is expressed on subsets of T cells and is a new marker of lymphomas of T follicular helper cell-derivation. Haematologica. 2010;95(3):432-439
3. Tan LH, Tan SY: Aberrant immunoarchitecture distinguishes hyperplastic germinal centres in pattern 1 angioimmunoblastic T-cell lymphoma from reactive follicles. Hematol Oncol 2014;32(3):145-154
4. Bosisio FM, Cerroni L: Expression of T-follicular helper markers in sequential biopsies of progressive mycosis fungoides and other primary cutaneous T-cell lymphomas. Am J Dermatopathol 2015;37(2):115-121
Method Description
Immunohistochemistry on sections of paraffin-embedded tissue.(Unpublished Mayo method)
Specimen Retention Time
Until staining is completeForms
If not ordering electronically, complete, print, and send an Immunohistochemical (IHC)/In Situ Hybridization (ISH) Stains Request (T763) with the specimen.
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| TECHONLY | Ambient (preferred) | ||
| Refrigerated | |||
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).