ROS1 with Interpretation by Immunohistochemistry with Reflex to FISH if Equivocal or Positive

Casandra

Casandra Test Code AR79634Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 2008414CPT Codes 88342, 88366

ROS1 with Interpretation by Immunohistochemistry with Reflex to FISH if Equivocal or Positive

Also known as: ROS1 IP

Clinical Use

Order Test

Use

The test is primarily used to determine the eligibility of patients with pulmonary adenocarcinomas for tyrosine kinase inhibitor therapy, specifically targeting the ROS1 fusion proteins and gene rearrangements. The detection of ROS1 rearrangements aids in identifying patients who may benefit from targeted tyrosine kinase inhibitor treatments such as crizotinib.

Special Instructions

The test is performed on formalin-fixed paraffin-embedded tumor tissue, requiring the submission of tissue blocks or slides. In case of multiple specimen submissions, specification of the best block or separate individual orders is necessary. A pathologist block selection fee may apply if ARUP pathologist chooses the specimen most appropriate for testing.

Limitations

The test was developed and its performance characteristics determined by ARUP Laboratories and should be performed in a CLIA-certified laboratory. It is important to note that it has not been cleared or approved by the US FDA. The assay is limited to detecting ROS1 fusion proteins and ROS1 gene rearrangements without identifying specific partner genes in rearrangements. Positive results in IHC require confirmation by FISH.

Test Details

New York Approved

Methodology

Immunoassay (IHC)

Biomarkers

2 components

Immunohistochemistry (IHC) • IHCFluorescence in situ hybridization (FISH) • FISH

LOINC Codes

Result Codes

55229-9
94736-6
31208-2

Result Turnaround Time

1-5 days

Specimen

Tissue (FFPE)

Volume

Not provided

Minimum Volume

6 slides

Container

Tissue transport kit (ARUP supply #47808)

Collection Instructions

Collect formalin fixed paraffin embedded tissue. Transport tissue block or 6 unstained, positively charged slides.

Storage Instructions

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

Causes for Rejection

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