CPT® Code 81246

FLT3 (fms-related tyrosine kinase 3) (eg, acute myeloid leukemia), gene analysis; tyrosine kinase domain (TKD) variants (eg, D835, I836)

The CPT® Code 81246 pertains to the molecular genetic testing of the FLT3 (fms-related tyrosine kinase 3) gene, specifically focusing on the analysis of tyrosine kinase domain (TKD) variants, such as D835 and I836. This gene is located on the q arm of chromosome 13 at position 12. The D835 variant is identified as a missense mutation occurring at the aspartic acid residue 835 and is found in approximately 7% of cases of acute myeloid leukemia (AML). AML is characterized by the clonal expansion of myeloid blast cells, which can infiltrate the blood, bone marrow, and other tissues, leading to a heterogeneous disease presentation. The identification of specific genetic variants within the FLT3 gene is crucial for personalizing treatment strategies, thereby enhancing the likelihood of achieving favorable patient outcomes. The FLT3 gene encodes a protein that is a member of the receptor tyrosine kinase (RTK) family, which plays a significant role in cellular signaling. These proteins interact with the FLT3 ligand on cell surfaces, triggering intracellular signaling pathways that regulate cell proliferation and survival, particularly in hematopoietic progenitor cells. To perform this genetic analysis, blood and/or bone marrow samples are collected, typically through venipuncture and/or bone marrow aspiration, which are separately reportable procedures. The testing for gene mutations is conducted using polymerase chain reaction (PCR) techniques, followed by amplification analysis through capillary electrophoresis to detect length mutations and assess resistance to EcoRV digestion.