13q deletion FISH
Also known as: 13q14 FISH, CLL FISH
Test category:
Oncology - Lymphoma
Use of test
Purpose:
Deletions affecting the long arm of Chromosome 13 can be found in a number of mature B-cell lymphoid neoplasms, particularly chronic lymphocytic leukaemia (CLL), and also splenic marginal zone lymphoma and mantle cell lymphoma. Testing provides information regarding prognosis.
Utility:
Presence of a 13q deletion as a sole abnormality is a positive prognostic sign in CLL.
Ethical considerations:
This is an assay for non-heritable mutations. It does not raise issues of ethics or consent that are different from most other investigations ordered in the routine care of a patient.
Methodology:
Fluorescent in situ hybridisation (FISH) analysis, using probes located within 13q. This interphase FISH test has a cut off at 5%. A low level of positive cells may be due to overlap of the two signals. Studies of normal controls indicate that this level is less than 5%.
Requesting the test
Ordering:
This test is usually requested by a haematologist or oncologist.
Sample required:
0.5 mL bone marrow in transport media, or 5-10 mL blood in lithium heparin.
To help ensure the quality of the test, a genetic test should be done with a dedicated sample whenever possible i.e. a sample collected specifically for that test rather than a sample that is used for multiple tests.
We recommend that the patient or another adult check the labelling of request forms and sample tubes.
Special instructions:
In CLL, this test is part of the CLL FISH panel.
Turnaround time:
5 business days.
Price:
Up to $255.
If more information is required, the requesting clinician can call our laboratory on (07) 3377 8573.
Rebate:
This test is not rebated by Medicare. The laboratory assumes that the patient or client has provided informed financial consent for the test.