Leanne Chiu

Launch of Province-Wide Lymphoma LExA Expression Assay

by

As of November 17, 2025, the Cancer Genetics and Genomics Laboratory (CGL) at BC Cancer is offering LExA gene expression profiling assay for diffuse large B-cell lymphomas and high grade B-cell lymphomas and will be available to all pathologists across the province for ordering.

The LExA assay is used to identify tumour cell-of-origin and the dark zone signature, both of which have prognostic and predictive utility. The LExA assay can also identify a signature that can discriminate primary mediastinal large B-cell lymphoma from diffuse large B-cell lymphoma NOS in the correct clinical setting.

LExA will replace FISH as the first-tier test for all diffuse large B-cell lymphomas and high grade B-cell lymphomas. FISH for MYC and BCL2 will be performed as a reflex test on any case that is dark zone positive or indeterminant by LExA or any cases that fails to provide an interpretable result by LExA. Additional information can be found in our memo. Further details, including methods and testing requirements, for LExA can be found here, and High Grade B-Cell Lymphoma can be found here.

The LExA assay can be ordered using the CGL Lymphoma Requisition found on our Requisitions page.

MAML2 – New FISH probe

by

As of August 18, 2025, the Cancer Genetics and Genomics Laboratory (CGL) at BC Cancer is offering a new FISH probe – MAML2 FISH for the indication of mucoepidermoid carcinoma (MEC) using a break-apart probe. This FISH assay will detect any rearrangement of MAML2, regardless of the fusion partner. Further details can be found here.

The specimen requirements for this new FISH probe are the same as other solid tumours and can be ordered by sending the following to CGL:

  • A completed CGL Cytogenetics Solid Tumour Testing requisition form.
  • An H&E stained slide with the tumour region circled, and the estimated % tumour content written in the Tumour Content field of the requisition.  
    NOTE: A minimum of 10% tumour and at least 200 nuclei is required.
  • Specimen block and two unstained slides.
  • See our FFPE Guidelines for additional details.