ROS1 by FISH (Lung cancer)

Alphabetical Test listing

ROS1 by FISH (Lung cancer)-4280J

ROS1 by FISH (Lung cancer)
Non-Small Cell Lung Cancer (NSCLC)

To Identify patients with late-stage, non-small cell lung cancers who may benefit from treatment with Xalkori (Crizotinib).

The ROS1 gene, a close evolutionary relative of ALK, encodes a receptor tyrosine kinase that activates some of the same signaling pathways as ALK. ROS1 rearrangements lead to constitutively active fusion proteins and are detected in 1% to 2% of NSCLC cases.

Malignant tumor tissue

Collect 5 mmsample of involved tissue (solid tumor or other) and place in sterile culture medium, sterile Hanks Balance Salt Solution (HBSS) or sterile saline within 1 hr of procedure


Submit 2 unstained 5 micron cuts of involved tissue mounted on positively charged slides and 1 H & E


a formalin-fixed, paraffin-embedded (FFPE) tumor block. An H & E will be cut and stained, and assessed by an HPA pathologist.

  • Specimen should be fixed in 10% neutral buffered formalin for 6 - 72 hours

FFPE block or slides

  • Cytogenetics oncology requisition or pathology Add-on form
  • Document time in fixation – specimen should be fixed in 10% neutral buffered formalin for 6 - 72 hours


Slides - 6 months for slides
Blocks will be returned post reporting
  • Improper label (unlabeled or mislabeled)
  • Wrong container (anticoagulant or solution)
  • Improper storage
  • Leaking container
  • Slides broken beyond repair
AHL - Cytogenetics: X
As needede
5 days

Fluorescence in situ hybridization (FISH)


>15% of nuclei scored displaying rearrangement a minimum of one 5’ and one 3’ ROS1, or a deletion of one 5’ROS1 only.

Results will be reported as either Positive or Negative for ROS1 rearrangement, or Uninformative.

88377 – Quantitative Morphometric FISH.

This test includes a charge for application of the 2 FISH probes and professional interpretation of the results. If no cells are available for analysis, no analysis charges will be incurred.