Test Directory

Test Code
FSMAL
Test Name
MALT1,18q21.31-q21.32 Gene Rearrangement by FISH (Heme)
CPT Codes
88237, 8837726, 88377TC
Included Tests

MALT1, 18q21.31-q21.32

Expected Turnaround Time
3-5 business days
Clinical Utility

Translocation (11;18)(q21;q21) has been associated with extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). Translocation (11;18) leads to the fusion of the apoptosis inhibitor-2 (API2) gene and the MALT lymphoma-associated translocation (MALT1) gene. However, it has been found that 18% of MALT lymphomas have t(14;18)(q32;q21) or a translocation involving the immunoglobulin heavy chain (IGH) and MALT1 gene. MALT lymphomas with t(11;18)(q21;q21) usually do not have additional genetic aberrations, which is in contrast to t(14;18)(q32;q21) cases. Aneuploidy is most often seen in the majority of t(14;18)(q32;q21) MALT lymphomas. FISH can detect this rearrangement in either interphase or metaphase cells.

Specimen and Container Info

Specimen

Containers

Volume

Leukemic Blood

Preferred Collection Container: Green Top (Sodium Heparin)

Alternate Collection Container: Lavendar Top (EDTA)

Desired Specimen Volume: 3 - 5 mL

Minimum Acceptable Volume: 1 mL

Bone Marrow

Preferred Collection Container: Green Top (Sodium Heparin)

Alternate Collection Container: Lavendar Top (EDTA)

Desired Specimen Volume: 3 - 5 mL

Minimum Acceptable Volume: 1 mL

Lymph Node

Sterile Collection Container with Supporting Media

Collection Instructions
  • Lithium heparin is not acceptable.
  • Specimens must be collected in a sterile collection container.
Processing and Submission Instructions

Each specimen must be accompanied by a requisition form, script, electronic order or physician note. Each order must indicate the reason for testing (diagnosis).

Transport Instructions
  • Transport to the laboratory at room temperature.
  • Store specimen as whole blood, in original tube, at room temperature and deliver to lab within 24 hours.
  • If specimen cannot be delivered within 24 hours, store in refrigerator. Do not freeze specimen.
  • Specimens collected on the weekends must be refrigerated upon arrival at HNL Lab Medicine.
Stability Requirements

Room Temperature

24 hours

Refrigerated

72 hours

Frozen

Do not freeze

Causes for Rejection
  • Specimen frozen
  • Specimen arriving without any form of patient identification (unlabeled)
  • Specimen with attached needles
  • Specimen arriving with broken or leaking collection tube
  • Unfixed specimen treated with fixative
Methodology
FISH, Fluorescence In-Situ Hybridization
Reference Intervals

In a normal cell, the expected signal pattern is two fusion signals. In an abnormal cell containing a rearrangement, the expected signal pattern is one red signal, one green signal, and one fusion signal.

Performing Location
Roble Road Core Laboratory
Alternate Names
  • FISH MALT1 Breakapart, Heme
  • MALT1 BA
  • MALT1
  • Mucosa-Associated Lymphoid Tissue Lymphoma Translocation Protein 1
Testing Schedule
Routine, Monday - Friday no holidays
Disease Group
Cytogenetic Tests