CSF3R-618 Mutational Analysis


CSF3R encodes the receptor for colony-stimulating factor 3, a cytokine that controls the production, differentiation, and function of granulocytes. Mutations in CSF3R have been associated with severe congenital neutropenia, and have recently been discovered to be associated with chronic neutrophilic leukemia and atypical chronic myeloid leukemia. Chronic neutrophilic leukemia (CNL) is a rare myeloproliferative neoplasm with approximately 200 cases reported to date. Atypical chronic myeloid leukemia (aCML) is relatively uncommon and is considered within the category of myeloproliferative/myelodysplastic neoplasms. Both these conditions are of concern as patients with either disease lack a specific molecular biomarker and may transform to acute leukemia. It has been demonstrated that CSF3R mutations can be found in approximately 50-60% of CNL and aCML patients, the most common of which is the membrane proximal mutation p.T618I. Determining the presence and the type of CSF3R mutations is valuable because they not only help with the differential diagnosis of leukocytosis but also exhibit sensitivity to different kinase inhibitors. Categorizing the type of CSF3R mutation in a patient with CNL/aCML will promote individualized therapy. MDL has developed a Sanger sequencing assay for exons 14 and 17 of the CSF3R gene to assess for mutations associated with CNL/aCML. Should known hotspot mutations in codons 611 and 618 in exon 14 of CSF3R be found, the MDL Pyrosequencing assay will be used for monitoring.



This assay is available as PCR-based DNA Pyrosequencing for codons 611 and 618 in exon 14 of the CSF3R gene.


Test Parameters

The assay is designed to detect mutations in codons 611 and 618 in exon 14 of CSF3R. The lower limit of sensitivity of detection is approximately one mutated cell per ten total cells within the sample (10%).


Turnaround Time

10 days


Sample Requirements

10 mL peripheral blood, 2-5mL bone marrow aspirate, or 5µg purified DNA. Tissue sections may also be utilized for testing purposes, and testing requires formalin-fixed, paraffin embedded tissue blocks or 4-10 unstained tissue sections on glass slides along with 1 H&E-stained section containing adequate amounts of tumor to be analyzed (see above sensitivity), with areas to be tested clearly indicated on the slides/block. Please provide a copy of the corresponding pathology report.


CPT Codes


Additional charges may apply for tissue extraction.

The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.