Overview: CALR Mutation TestIntroduction: The CALR Mutation Test detects CALR gene mutations linked to blood disorders like myelofibrosis, causing fatigue or enlarged spleen. Following 2023 ASH guidelines, it uses PCR for high specificity, aiding in cancer screening. This test is critical for guiding diagnosis, treatment, and improving outcomes in molecular pathology for patients with suspected myeloproliferative disorders.
Other Names: CALR Gene Assay, Myelofibrosis Mutation Test.
FDA Status: Laboratory-developed test (LDT), meeting molecular pathology standards for diagnostic accuracy.
Historical Milestone: CALR mutation testing began in the 2010s with myeloproliferative disorder research. PCR-based assays improved diagnostic accuracy for myelofibrosis and related conditions.
Purpose: Diagnoses myeloproliferative disorders, guides treatment, and monitors CALR mutations in patients with fatigue or enlarged spleen.
Test Parameters: 1. CALR Mutation
Pretest Condition: No fasting required. Collect whole blood, bone marrow, or saliva at any time. Report symptoms like fatigue or splenomegaly, and list medications like JAK inhibitors.
Specimen: 2-5 mL whole blood (EDTA), 2-5 mL bone marrow (EDTA), or 1-2 mL saliva (sterile container). Transport in a biohazard bag within 24 hours.
Sample Stability at Room Temperature: 24 hours
Sample Stability at Refrigeration: 48 hours
Sample Stability at Frozen: Not frozen
Medical History: Document fatigue, splenomegaly, or family history of blood disorders. Include current medications, especially JAK inhibitors or chemotherapy.
Consent: Written consent required, detailing the tests purpose, diagnostic implications, and potential need for targeted therapy.
Procedural Considerations: Uses PCR to detect CALR mutations. Results are available in 3-5 days, supporting clinical decisions.
Factors Affecting Result Accuracy: Low sample quality or improper storage can reduce sensitivity. Contamination may cause false positives.
Clinical Significance: Positive CALR mutations confirm myelofibrosis, prompting JAK inhibitor therapy. Negative results suggest alternative diagnoses.
Specialist Consultation: Consult a hematologist for result interpretation. An oncologist referral is advised for myeloproliferative disorders.
Additional Supporting Tests: JAK2 mutation test, bone marrow biopsy, or CBC to confirm myelofibrosis or assess disease extent.
Test Limitations: False negatives may occur with low mutation levels. Results require clinical correlation with pathology.
References: ASH Myelofibrosis Guidelines, 2023; Blood, Tefferi A, 2022.
