Alternative Name
BTK, BTK primary susceptibility
Methodology
Molecular
Test Description

Concurrent analysis of the following by bi-directional sequencing: CARD11 exons 5 and 6, CD79B exon 5 including common Y196 mutations, CXCR4 C-terminus region, and MYD88 exon 5 including the L265P mutation.

Clinical Significance

This panel detects mutations in four genes associated with primary (initial) susceptibility or resistance to BTK (Bruton tyrosine kinase) inhibitors in certain B-cell neoplasms. Mutations in MYD88 and CD79B are associated with inhibitor sensitivity, and mutations in CARD11 and CXCR4 are associated with primary resistance. Mutation presence may also have prognostic significance. This panel is appropriate for patients with B-cell neoplasms, particularly diffuse large B-cell lymphoma (DLBCL), who are candidates for BTK inhibitor therapy or are not responding to such therapy. Mutation detection can guide the selection of alternative therapeutic options.

Specimen Requirements
  • Peripheral blood: 5 mL in EDTA tube.
  • Bone marrow: 2 mL in EDTA tube.
  • FFPE tissue: Paraffin block is preferred. Alternatively, send 1 H&E slide plus 5-10 unstained slides cut at 5 or more microns. Please use positively-charged slides and 10% NBF fixative. Do not use zinc fixatives.
Storage and Transportation

Use cold pack for transport. Make sure cold pack is not in direct contact with specimen.

CPT Code(s)*
81479x1
Turnaround Time

10 days

Level of Service
Global

*The CPT codes provided with our test descriptions are based on AMA guidelines and are for informational purposes only. Correct CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed.