Test Catalog

Test ID: TLBLF    
T-Lymphoblastic Leukemia/Lymphoma, FISH, Tissue

Method Description Describes how the test is performed and provides a method-specific reference

This test uses FISH enumeration strategy probes to detect deletions of CDKN2A(p16) on chromosome 9p and TP53 on chromosome 17p. Dual-color, break-apart (BAP) probes are used to detect rearrangements of the TAL1/STIL(SIL), TRB(TCR beta), MLL, and TRAD(TCR alpha delta) locus on 1p33, 7q34, 11q23, and 14q11.2, respectively. Dual-color, dual-fusion strategy (D-FISH) probe sets are used to detect fusions of the TLX3(HOX11L2)/BCL11B, ABL1(ABL)/BCR, and MLLT10(AF10)/PICALM  locus on (5;14)(q35;q32), (9;22)(q34;q11.2), and (10;11)(p12;q14) respectively. D-FISH probe sets are also used in reflext testing when rearrangements of MLL, TRAD(TCR alpha delta) and TRB(TCR beta) gene loci are detected. Amplification of the ABL1 gene is detected using a D-FISH probe strategy. Paraffin-embedded tissues are cut at 5 microns and mounted on positively charged glass slides. The selection of tissue and the identification of target areas on the hematoxylin and eosin- (H and E) stained slide are performed by a pathologist. Using the H and E-stained slide as a reference, target areas are etched with a diamond-tipped etcher on the back of the unstained slide to be assayed. For each probe set, the probes are hybridized to the appropriate target areas and 2 technologists each analyze 50 interphase nuclei (100 total) per probe set with the results expressed as the percent abnormal nuclei.(Unpublished Mayo method)

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.

Specimens are processed Monday through Sunday.

Results reported Monday through Friday, 8 a.m.-5 p.m.

Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.

7 days

Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Clinic Laboratories until the release of the test result

10 days

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

Slides and H&E used for analysis are retained by the laboratory in accordance to CAP and NYS requirements. Client provided paraffin blocks and extra unstained slides (if provided) will be returned after testing is complete.

Performing Laboratory Location Indicates the location of the laboratory that performs the test