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BCL-2 t(14,18)

P BCL2

Test Synonym:

Follicular cell lymphoma, large cell lymphoma

Test Synonym:

83891 – Molecular isolation
83894 – Separartion by gel electrophoresis

83900 – Amplification first two sequences
83901x3 – Amplification each additional sequence

83909 –   Identification
83912 – Interpretation and report

Turnaround Time:

3 days

Methodology:

Polymerase Chain Reaction (PCR), capillary gel electrophoresis

Specimen Requirements:

  • 5.0 ml (min. 3.0ml) EDTA whole blood
  • 3.0 ml (min. 1.0ml) EDTA bone marrow;
  • 5mm3 bone marrow core biopsy,
  • Fresh or frozen tissue in MPLN RPMI
  • 3.0ml (min. 2.0ml) FNA in MPLN RPMI medium;
  • Formalin fixed paraffin-embedded tissue

    • Causes for Rejection:

    Insufficient volume; specimen at incorrect temperature, incorrect anticoagulant or fixative

    Specimen Stability:

  • EDTA whole blood or bone marrow stable at 18-25°C for 72 hours
  • Bone marrow biopsy, fresh tissue or FNA in MPLN RPMI at 2-8°C stable for 72 hour
  • Frozen tissue at -20°C stable indefinitely;  paraffin-embedded tissue at 18-25°C stable indefinitely

    • Storage and Handling:

  • EDTA whole blood, bone marrow, bone marrow biopsy,
  • Fresh tissue or FNA, ship in a styrofoam container with an ice pack (do not allow the ice pack to directly contact the sample);
  • Frozen tissue ship on dry ice;
  • Paraffin-embedded tissue ship ambient

    • Reference Range:

    BCL-2 gene rearrangement not detected

    Indication:

    The BCL-2 gene on chromosome 18 is juxtaposed to the IgH join (JH) gene on chromosome 14. The BCL-2 gene encodes an oncogene product that functions to inhibit apoptosis; over expression leads to prolonged cell life and associated increased risk of neoplastic transformation. The presence of the translocation [t(14;18)(q32;q21)] is present in ~70% of follicular lymphomas and ~30% of diffuse large cell lymphomas. The presence of t(14;18) provides differentiation from other B cell lymphomas with similar morphology, such as mantle cell lymphoma or MALT lymphoma1-6. Identification of BCL-2 translocation is performed preferentially by FISH due to its ability to detect >95% of cases with the t(14;18). Whereas PCR1-3 detects the major breakpoint region (mbr/JH) clustered on chromosome 18 and the minor cluster region (mcr/JH); these account for 50-60% and 10-20% of follicular lymphoma cases, respectively1. For differential diagnosis FISH is the preferred technique having almost 100% specificity. Once diagnosis is accomplished, however, PCR can be used to monitor patients for disease relapse after treatment.

    References:

    1. Meier et al. (2001). Simultaneous evaluation of T- and B-cell clonality, t(11;14) and t(14;18), in a single reaction by a four-color multiplex polymerase chain reaction assay and automated high-resolution fragment analysis: a method for the rapid molecular diagnosis of lymphoproliferative disorders applicable to fresh frozen and formalin-fixed, paraffin-embedded tissues, blood, and bone marrow aspirates. AJP 159(6):2031
    2. Medeiros et al (1999). Review. Overview of the role of molecular methods in the diagnosis of malignant lymphomas. Arch Pathol Lab Med 123(12):1189
    3. Pezzella et al. (1990). The 14;18 translocation in European cases of follicular lymphoma: comparison of Southern blotting and the polymerase chain reaction. Br J Haematol. 76(1):58
    4. Crisan et al. (1993). BCL-2 gene rearrangements in follicular lymphomas. Lab Med  24:579
    5. Yanis et al. (1989). BCL-2 Oncogene Rearrangement in Follicular and Diffuse Large-Cell and Mixed-Cell Lymphoma. Cancer Cells 7:37
    6. Weiss et al. (1987). Molecular Analysis of the t(14;18) Chromosomal Translocation in Malignant Lymphomas. N Engl J Med  317(19):1185