Use of test
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.
Presence of a 13q deletion as a sole abnormality is a positive prognostic sign in CLL.
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.
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
This test is usually requested by a haematologist or oncologist.
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.
In CLL, this test is part of the CLL FISH panel.
5 business days.
Up to $255.
If more information is required, the requesting clinician can call our laboratory on (07) 3377 8573.
This test is not rebated by Medicare. The laboratory assumes that the patient or client has provided informed financial consent for the test.