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Immunohistochemistry Stain Form Recommended (ARUP form #32978)
Ordering Recommendation

Determine eligibility for tyrosine kinase inhibitor (TKI) (eg, crizotinib) therapy, primarily in individuals with pulmonary adenocarcinomas. Detects ROS1 fusion proteins (IHC) and ROS1 gene rearrangements (FISH).

Mnemonic
ROS1 IP
Methodology

Immunohistochemistry

Performed

Mon-Fri

Reported

1-5 days, add 3-5 days if reflexed

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

Tumor tissue

Specimen Preparation

Formalin fix (10 percent neutral buffered formalin) and paraffin embed tissue. Transport tissue block or 6 unstained (3- to 5-micron thick sections), positively charged slides in a tissue transport kit (ARUP supply #47808) available online through eSupply using ARUP Connect or contact ARUP Client Services at (800)522-2787. (Min: 6 slides) If sending precut slides, do not oven bake.

Storage/Transport Temperature

Room temperature or refrigerated. Ship in cooled container during summer months.

Unacceptable Conditions

Paraffin block with no tumor tissue remaining. Specimens fixed in any other fixative other than 10 percent neutral buffered formalin. Cytology specimens fixed in alcohol. Decalcified specimens.

Remarks

Include pathology report. IMMUNOHISTOCHEMISTRY ORDERING AND SUBMISSION DETAILS: Submit electronic request. If you do not have electronic ordering capability, use an ARUP Immunohistochemistry form (#32978) with an ARUP client number. For additional technical details, please contact ARUP Client Services at (800) 522-2787.

Stability

Ambient: Indefinitely; Refrigerated: Indefinitely; Frozen: Unacceptable

Reference Interval
Interpretive Data

Refer to report.

Compliance Category

Laboratory Developed Test (LDT)

Note

If ROS1by Immunohistochemistry result is equivocal or positive, then ROS1 by FISH will be added. Additional charges apply.

Hotline History
N/A
CPT Codes

88342; if reflexed, add 88366

Components
Component Test Code* Component Chart Name LOINC
2008415 ROS1 by IHC Result
2008417 ROS1 Client Block ID
3003121 ROS1 Tissue Source
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • ROS1 IHC
  • ROS1 IHC with Interpretation
  • ROS1 immunostaining
ROS1 with Interpretation by Immunohistochemistry with Reflex to FISH if Equivocal or Positive