Test ID: 89041
T-Cell Lymphoma, FISH, Tissue

Detecting a neoplastic clone associated with the common chromosome abnormalities seen in patients with various T-cell lymphomas

Tracking known chromosome abnormalities and response to therapy in patients with T-cell neoplasms

This panel includes a mini-pathology consultation to evaluate appropriate FISH probes and translocations to investigate. Panel includes testing for the following anomalies via the probes listed:

t(14;var)(q32.1;var), TCL1A

-7/7q-/i(7q), D7S486/Cen7

+8, Cen8/MYC

t(2;var)(p23.2;var)/inv(2), ALK

If the patient is being tracked for known anomalies, indicate which anomalies need to be investigated.

When this test is ordered, a charge for 2 FISH probes and interpretation is included. If additional probes or the entire panel are ordered, additional probe charges will be added.

• Cytogenetics Hematologic FISH Panel Patient Information Sheet

Fluorescence In Situ Hybridization (FISH) with DNA Probes

Provide a reason for referral with each specimen. The laboratory will not reject testing if this information is not provided, but appropriate testing and interpretation may be compromised or delayed.

Forms:

1. Cytogenetics Hematologic FISH Panel Patient Information Sheet (Supply T603) in Special Instructions

2. If not ordering electronically, submit a Cytogenetics Hematologic Disorders Request Form (Supply T607) with the specimen.

Advise Express Mail or equivalent if not on courier service.

Submit only 1 of the following specimens:

Specimen Type: Lymph node

Collection Instructions:

1. Submit paraffin block with 1 corresponding hematoxylin-and-eosin slide. Unstained slides are not preferred but are acceptable.

2. Although formalin is the preferred fixative, tissue blocks may be fixed with B5 fixative.

3. Blocks will have core biopsies punched out to isolate nuclei to process for analysis.

Specimen Type: Solid tumor

Collection Instructions:

1. Submit paraffin block with 1 corresponding hematoxylin-and-eosin slide. Unstained slides are not preferred but are acceptable.

2. Although formalin is the preferred fixative, tissue blocks may be fixed with B5 fixative.

3. Blocks will have core biopsies punched out to isolate nuclei to process for analysis.

T-cell malignancies account for approximately 12% of all non-Hodgkin lymphomas. There are several subtypes of T-cell neoplasms: T-cell acute lymphoblastic leukemia (T-ALL), T-cell prolymphocytic leukemia (T-PLL), T-cell large granular lymphocytic leukemia (T-LGL), anaplastic large cell lymphoma (ALCL), peripheral T-cell lymphoma, and various other cutaneous, nodal, and extrandodal lymphoma subtypes. The 2 most prevalent lymphoma subtypes are unspecified peripheral T-cell lymphoma (3.7%) and ALCL (2.4%).

A few common chromosome abnormalities are associated with specific T-cell lymphoma subtypes, including:

-inv (14)(q11q32) and t(14;14)(q11;q32) involving the T-cell leukemia/lymphoma 1 gene (TCL1A) at 14Q32

-Translocations involving the ALK gene at 2p23 in ALCL

-Isochromosome 7q and trisomy 8 in hepatosplenic T-cell lymphoma

T-ALL is a neoplastic disorder of lymphoblasts committed to the T-cell lineage. These malignancies comprise 15% to 20% of acute leukemias. While half of T-ALL patients have normal chromosome studies, molecular cytogenetic analysis can identify abnormalities including:

These abnormalities may be seen in tissues (ie, lymph nodes), as well as in blood and bone marrow.

This tissue-based assay detects the common chromosome abnormalities observed in T-cell lymphoma and T-ALL (for blood and bone marrow in patients with T-ALL, see FRTAL/88783 T-Cell Acute Lymphoblastic Leukemia [T-ALL], FISH; for all other T-cell lymphomas, see FRTLP/89040 T-Cell Lymphoma, FISH, Blood or Bone Marrow). These probes have diagnostic relevance and can also be used to track response to therapy.

An interpretive report will be provided.

A neoplastic clone is detected when the percent of cells with an abnormality exceeds the normal reference range for any given probe.

Detection of an abnormal clone is supportive of a diagnosis of a T-cell lymphoma or T-cell acute lymphoblastic leukemia. The specific anomaly detected may help subtype the neoplasm.

The absence of an abnormal clone does not rule out the presence of a neoplastic disorder.

This test is not FDA approved and it is best used as an adjunct to existing clinical and pathologic information.

1. World Health Organization Classification of Tumours. Pathology and Genetics of Tumours of aematopoietic and Lymphoid Tissues. Edited by ES Jaffe, NL Harris, H Stein, JW Vardiman. Lyon, IARC Press, 2001

2. Gesk S, Martin-Subero JI, Harder L, et al: Molecular cytogenetic detection of chromosomal breakpoints in T-cell receptor gene loci. Leukemia 2003;17:738-745

3. Chin M, Mugishima H, Takamura M, et al: Hemophagocytic syndrome and hepatosplenic (gamma)(delta) T-cell lymphoma with isochromosome 7q and 8 trisomy. J Pediatr Hematol Oncol 2004;26(6):375-378

4. Graux C, Cools J, Michaux L, et al: Cytogenetics and molecular genetics of T-cell acute lymphoblastic leukemia: from thymocyte to lymphoblast. Leukemia 2006;20:1496-1510

5. Cayuela JM, Madani A, Sanhes L, et al: Multiple tumor-suppressor gene 1 inactivation is the most frequent genetic in T-cell lymphoblastic leukemia. Blood 1996;87:3180-3186

Abnormalities involving TCL1 and ALK are detected using break-apart FISH probes. Trisomy of chromosome 8, isochromosome 7q, are detected using enumeration strategies. A combination of commercially available and Mayo laboratory-developed probes are utilized. For each probe set, 200 interphase nuclei are scored and results for each abnormal probe is expressed as percent abnormal nuclei. (Unpublished Mayo method)

Samples processed Monday through Sunday. Results reported Monday through Friday, 8 a.m.-5 p.m. CST.

T-Cell Lymphoma, FISH, Tissue

88271 x 2-DNA probe, each

88275-Interphase in situ hybridization, 100 to 300 cells

88291-Interpretation and report

One Additional FISH Probe

88271-DNA probe, each (if appropriate)

88275-Interphase in situ hybridization (if appropriate)

Two Additional FISH Probes

88271 x 2-DNA probe, each (if appropriate)

88275-Interphase in situ hybridization (if appropriate)

Three Additional FISH Probes

88271 x 3-DNA probe, each (if appropriate)

88275-Interphase in situ hybridization (if appropriate)

Four Additional FISH Probes

88271 x 4-DNA probe, each (if appropriate)

88275 x 2-Interphase in situ hybridization (if appropriate)

Five Additional FISH Probes

88271 x 5-DNA probe, each (if appropriate)

88275 x 2-Interphase in situ hybridization (if appropriate)

Six Additional FISH Probes

88271 x 6-DNA probe, each (if appropriate)

88275 x 3-Interphase in situ hybridization (if appropriate)

Seven Additional FISH Probes

88271 x 7-DNA probe, each (if appropriate)

88275 x 3-Interphase in situ hybridization (if appropriate)

Eight Additional FISH Probes

88271 x 8-DNA probe, each (if appropriate)

88275 x 4-Interphase in situ hybridization (if appropriate)

Nine Additional FISH Probes

88271 x 9-DNA probe, each (if appropriate)

88275 x 4-Interphase in situ hybridization (if appropriate)

Ten Additional FISH Probes

88271 x 10-DNA probe, each (if appropriate)

88275 x 5-Interphase in situ hybridization (if appropriate)

Eleven Additional FISH Probes

88271 x 11-DNA probe, each (if appropriate)

88275 x 5-Interphase in situ hybridization (if appropriate)

Twelve Additional FISH' Probes

88271 x 12-DNA probe, each (if appropriate)

88275 x 6-Interphase in situ hybridization (if appropriate)

Thirteen Additional FISH Probes

88271 x 13-DNA probe, each (if appropriate)

88275 x 6-Interphase in situ hybridization (if appropriate)

Fourteen Additional FISH Probes

88271 x 14-DNA probe, each (if appropriate)

88275 x 7-Interphase in situ hybridization (if appropriate)

Fifteen Additional FISH Probes

88271 x 15-DNA probe, each (if appropriate)

88275 x 7-Interphase in situ hybridization (if appropriate)

Sixteen Additional FISH Probes

88271 x 16-DNA probe, each (if appropriate)

88275 x 8-Interphase in situ hybridization (if appropriate)

Seventeen Additional FISH Probes

88271 x 17-DNA probe, each (if appropriate)

88275 x 8-Interphase in situ hybridization (if appropriate)

Eighteen Additional FISH Probes

88271 x 18-DNA probe, each (if appropriate)

88275 x 9-Interphase in situ hybridization (if appropriate)

Nineteen Additional FISH Probes

88271 x 19-DNA probe, each (if appropriate)

88275 x 9-Interphase in situ hybridization (if appropriate)

Twenty Additional FISH Probes

88271 x 20-DNA probe, each (if appropriate)

88275 x 10-Interphase in situ hybridization (if appropriate)