Overview: IgM Surface Flow Cytometry Test
Introduction: The IgM Surface Flow Cytometry Test detects surface IgM heavy chain to diagnose lymphoma, causing fever or weight loss. Following 2023 ASH guidelines, it uses flow cytometry for high specificity, aiding in cancer screening. This test is critical for guiding diagnosis, treatment, and improving outcomes in hematology for patients with suspected lymphoma.

Other Names: IgM Surface Flow Assay, B-Cell Surface IgM Test.

FDA Status: Laboratory-developed test (LDT), meeting hematology standards for diagnostic accuracy.

Historical Milestone: Surface IgM testing began in the 1990s with lymphoma research. Flow cytometry panels emerged in the 2000s, improving accuracy for surface marker detection.

Purpose: Diagnoses lymphoma, guides treatment, and monitors surface IgM heavy chain in patients with fever or weight loss.

Test Parameters: 1. IgM Heavy Chain (Surface)

Pretest Condition: No fasting required. Collect whole blood or bone marrow at any time. Report symptoms like fever or weight loss, and list medications.

Specimen: 2-5 mL whole blood (EDTA) or 2-5 mL bone marrow (EDTA). 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 fever, weight loss, or history of lymphoma. Include current medications, especially chemotherapeutics.

Consent: Written consent required, detailing the tests purpose, diagnostic implications, and potential need for cancer therapy.

Procedural Considerations: Uses flow cytometry to detect surface IgM heavy chain. Results are available in 1-2 days, enabling rapid clinical decisions.

Factors Affecting Result Accuracy: Poor sample quality or low cell yield can affect results. Non-malignant conditions may express surface IgM.

Clinical Significance: Positive surface IgM expression suggests lymphoma, prompting treatment. Negative results may require additional marker testing.

Specialist Consultation: Consult a hematologist or oncologist for result interpretation.

Additional Supporting Tests: Bone marrow biopsy, other flow cytometry markers (e.g., CD19, CD20), or PET scan to confirm lymphoma.

Test Limitations: Non-specific expression may occur in non-malignant conditions. Results require clinical correlation.

References: ASH Lymphoma Guidelines, 2023; Blood, Swerdlow SH, 2022.