Test Directory

ALK, 2p23.2-p23.1

The LSI dual break-apart rearrangement probe contains two differently labelled probes on either side of the breakpoint of the anaplastic lymphoma kinase (ALK) gene. ALK has multiple fusion partners including nucleophasmin (NPM1) in anaplastic large cell lymphoma and echinoderm microtubule-associated protein 4 (EML4) in non- small cell lung cancer. EML4/ALK fusions are the result of paracentric inversions involving the short arm of chromosome 2. The breakpoints of the inversions are within the EML4 locus (2p21) and the ALK locus (2p23). FISH can detect this rearrangement in either interphase or metaphase cells.

Specimen: Formalin-Fixed Paraffin Embedded (FFPE) Tissue Block or 2 slides from FFPET block, cut at 4 micron thickness and mounted on charged lysine slides with accompanying H&E slide indicating the region(s) of interest (ROI), if the entire specimen is not tumor.

Specimens should have an ischemia time of < 1 hour and a formalin fixation time of

6 - 72 hours.

Transport to the laboratory at room temperature.

• Specimen arriving without any form of patient identification (unlabeled)
• FFPET sections that are not properly attached to the slide
• FFPET sections with excessive cracks, splits or deterioration that would inhibit analysis
• Broken FFPET slides

In a normal cell, the expected signal pattern is two fusion signals. In an abnormal cell containing a rearrangement, the expected signal pattern is one red signal, one green signal, and one fusion signal.

• FISH ALK Breakapart
• ALK BA
• ALK
• Anaplastic Lymphoma Kinase