NTRK Genes Mutation Analysis, Next-Generation Sequencing, Tumor

Casandra

Casandra Test Code MC18552Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID NTRKMCPT Codes 81479, 88381

NTRK Genes Mutation Analysis, Next-Generation Sequencing, Tumor

Clinical Use

Use

This test uses targeted next-generation sequencing to evaluate for somatic mutations within the NTRK1, NTRK2, and NTRK3 genes. It is specifically used for identifying NTRK mutations that may predict resistance to Trk inhibitors. These mutations are found within solid tumor samples, and the presence of an NTRK mutation may indicate resistance to first-generation Trk inhibitors, which helps in guiding patient management and therapy decisions particularly in cases where resistance is expected, and alternative treatments or second-generation inhibitors need consideration.

Special Instructions

A pathology report, containing the patient name, block number, tissue collection date, and source of the tissue, must accompany the specimen for testing. Formalin-fixed, paraffin-embedded (FFPE) tissue blocks or slides are used as specimens. Ensure adequate tumor nuclei, with a minimum of 20% required for testing. Multiple oncology gene panels are available, and a selection guide is recommended for proper test choice.

Limitations

This test does not assess germline alterations within the listed genes. A minimum of 20% tumor content is crucial for test accuracy. Variants of uncertain significance may be identified. The test may detect single exon deletions but does not capture multi-exon deletions, duplications, larger-scale genomic copy number variations, or epigenetic changes like promoter methylation. Results should be interpreted concerning clinical and other laboratory data, and additional testing may be necessary if there is a hereditary risk.

Test Details

New York Approved