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

Detecting a neoplastic clone associated with the common chromosome abnormalities seen in patients with T-cell lymphoblastic leukemia or lymphoma

This test may be ordered in 2 distinct ways allowing different combinations of probes to be utilized based on the clinical question, including the standard (diagnostic) TLBL FISH panel and the individual TLBL FISH probes (per client request).

The specific TLBL FISH panel or probes requested must be noted on the request form or in the reason for referral. If no specific panel or FISH probes are indicated, the standard (diagnostic) panel will be performed.

The standard (diagnostic) panel includes testing for the following abnormalities, using the FISH probes listed:

-1p33 rearrangements, TAL1/STIL(SIL)

-t(5;14)(q35;q32), TLX3(HOX11L2)/BCL11B

-7q34 rearrangements, TRB(TCR beta)

-9p-, CDKN2A(p16)/D9Z1

-t(9;22)(q34;q11.2), ABL1 amplification, ABL1(ABL)/BCR

-t(10;11)(p12;q14), MLLT10(AF10)/PICALM

-11q23 rearrangements, MLL

-14q11.2 rearrangements, TRAD (TCR alpha delta)

-17p-, TP53/D17Z1

When an MLL rearrangement is identified, reflex testing will be performed with 1 or more dual-fusion probe sets (D-FISH) in an attempt to identify the translocation partner. Probes include:

-t(4;11)(q21;q23), AFF1(AF4)/MLL

-t(6;11)(q27;q23), MLLT4(AF6)/MLL

-t(9;11)(p22;q23), MLLT3(AF9)/MLL

-t(10;11)(p12;q23), MLLT10(AF10)/MLL

-t(11;19)(q23;p13.1), MLL/ELL

-t(11;19)(q23;p13.3), MLL/MLLT1(ENL)

When an TRB(TCR beta) rearrangement is identified, reflex testing will be performed with a dual-fusion probe sets

(D-FISH) in an attempt to identify the translocation partner.

-t(7;10)(q34;q24), TRB(TCR beta)/TLX1(HOX11)

When an TRAD(TCR alpha delta) rearrangement is identified, reflex testing will be performed with a dual-fusion probe sets

(D-FISH) in an attempt to identify the translocation partner.

-t(10;14)(q24;q11.2), TLX1(HOX11)/TRAD(TCR alpha delta)

This test includes a charge for application of the first probe set (2 FISH probes) and professional interpretation of results. Additional charges will be incurred for all reflex probes performed. Analysis charges will be incurred based on the number of cells analyzed per probe set. If no cells are available for analysis, no analysis charges will be incurred.

Fluorescence In Situ Hybridization (FISH)