TEST CATALOG ORDERING & RESULTS SPECIMEN HANDLING CUSTOMER SERVICE EDUCATION & INSIGHTS
Test Catalog

Test ID: BLYM    
B-cell Lymphoma, FISH, Tissue

Useful For Suggests clinical disorders or settings where the test may be helpful

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

 

Tracking known chromosome abnormalities and response to therapy in patients with B-cell lymphomas

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

This test does not include a pathology consultation. If a pathology consultation is desired, PATHC / Pathology Consultation should be ordered and the appropriate FISH test will be ordered and performed at an additional charge. Mayo Hematopathology Consultants are involved in both the preanalytic (tissue adequacy and probe selection, when applicable) and postanalytic (interpretation of FISH results in context of specific case, when applicable) phases.

 

 

Depending on the lymphoma subtype suspected, the most appropriate probes to order are listed in the table: Common Chromosome Abnormalities in B-cell Lymphomas in Clinical Information.

 

If the patient is being tracked for known abnormalities, indicate which probes should be used.

 

A charge and CPT code is applied for each probe set hybridized, analyzed, and reported.

 

Initial probe sets are run and completed within 4 days. If, based on testing algorithms, results of the initial probe sets require reflex testing, complete results will be available within 10 days.

 

The following algorithms are available in Special Instructions:

-Aggressive B-cell Lymphoma Diagnostic Algorithm

-Gastric MALT Lymphoma Diagnostic Algorithm

-Gastric MALT Posttherapy Follow-up Algorithm

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Mature B-cell lymphoma can be low grade, intermediate grade, or high grade, and the prognosis and clinical course are highly variable. Genetic abnormalities have emerged as one of the most important prognostic markers in B-cell lymphomas and can aid in diagnosis. Several chromosome abnormalities and variants of these abnormalities have been associated with various lymphoma subtypes (see table). Conventional chromosome studies cannot be employed on paraffin-embedded tissue, and molecular genetic analyses are often problematic in the study of lymphomas. FISH permits the detection of abnormal gene associated with various chromosome translocations and inversions in B-cell lymphoma (see table).

 

Common Chromosome Abnormalities in B-cell Lymphomas

 Lymphoma Type

 Chromosome Abnormality

  FISH Probe

Burkitt (pediatric,
< or =18 years old)

8q24.1 rearrangement

5'/3' MYC

t(2;8)(p12;q24.1)

IGK/MYC

t(8;14)(q24.1;q32)

MYC/IGH

t(8;22)(q24.1;q11.2)

MYC/IGL

3q27 rearrangement

3'/5' BCL6

18q21 rearrangement

3'/5' BCL2

Diffuse large B-cell, Burkitt-like "double-hit"

8q24.1 rearrangement

5'/3' MYC

t(8;14)(q24.1;q32)

MYC/IGH

----Reflex: t(2;8)(p12;q24.1)

IGK/MYC

----Reflex: t(8;22)(q24.1;q11.2)

MYC/IGL

----Reflex: 3q27 rearrangement

3'/5' BCL6

----Reflex: 18q21 rearrangement

3'/5' BCL2

Large BCL with IRF4 Rearranged

6p24.3 rearrangement

3'/5' IRF4

18q21 rearrangement

3'/5' BCL2

3q27 rearrangement

3'/5' BCL6

Follicular

18q21 rearrangement

3'/5' BCL2

3q27 rearrangement

3'/5' BCL6

Predominantly diffuse subtype only: deletion of 1p36

TNFRSF14/1q22

Mantle Cell

t(11;14)(q13;q32)

CCND1/IGH

Blastoid subtype only: deletion of 17p

TP53/D17Z1

Blastoid subtype only: 8q24.1 rearrangement

5'/3' MYC

MALT

18q21 rearrangement

5'/3' MALT1

Splenic Marginal Zone

Deletion of 7q

D7Z1/7q32

Deletion of 17p

TP53/D17Z1

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

An interpretive report will be provided.

Interpretation Provides information to assist in interpretation of the test results

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 B-cell lymphoma. The specific abnormality detected may help subtype the neoplasm.

 

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

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

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

 

Fixatives other than formalin (eg, Prefer, Bouin) may not be successful for FISH assays.

 

Paraffin-embedded tissues that have been decalcified are generally unsuccessful for FISH analysis. The pathologist reviewing the hematoxylin and eosin-stained slide may find it necessary to cancel testing.

Supportive Data

Each probe was independently tested on a set of formalin-fixed, paraffin-embedded tissue specimens from patients diagnosed with a B-cell lymphoma and noncancerous lymph node specimens. Normal cutoffs were calculated based on the results from 25 normal specimens. For each probe set, a series of chromosomally abnormal specimens were evaluated to confirm each probe set detected the anomaly it was designed to detect.

Clinical Reference Recommendations for in-depth reading of a clinical nature

WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. Edited by SH Swerdlow, E Campo, NL Harris. IARC, Lyon 2017

Special Instructions Library of PDFs including pertinent information and forms related to the test