Test Catalog

Test ID: SLL    
Small Lymphocytic 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 small lymphocytic lymphoma (SLL) and other low-grade B-cell lymphomas


Distinguishing patients with 11;14 translocations who have mantle cell lymphoma from patients who have SLL

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 consult. If a pathology consult is requested, 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 pre-analytic (tissue adequacy and probe selection, when applicable) and post-analytic (interpretation of FISH results in context of specific case, when applicable) phases.


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


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


Panel includes testing for the following abnormalities using the probes listed:

6q-, D6Z1/MYB

11q-, D11Z1/ATM

+12, D12Z3/MDM2

13q-, D13S319/LAMP1

17p-, TP53/D17Z1

t(11;14), CCND1/IGH


When an IGH rearrangement is identified, reflex testing will be performed to identify the translocation partner. Probes include identification of t(14;18)(q32;q21) IGH/BCL2 and t(14;19)(q32;q13) IGH/BCL3.


This assay detects chromosome abnormalities observed in paraffin-embedded tissue samples from patients with small lymphocytic lymphoma. For testing blood and bone marrow of patients with chronic lymphocytic leukemia, order CLLF / Chronic Lymphocytic Leukemia (CLL), FISH.

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

Small lymphocytic lymphoma (SLL) is the nonleukemic form of chronic lymphocytic leukemia (CLL), the most common adult leukemia in North America. The most common cytogenetic abnormalities detected in CLL are deletions of 6q, 11q, 13q, and 17p, trisomy 12, and the occasional occurrence of IGH translocations at 14q32. Cytogenetics has proven to be a reliable predictor of outcome for patients with CLL. It is unknown if SLL has the same prognostic significance when these genetic abnormalities are observed.


This FISH test detects an abnormal clone in approximately 65% of patients with SLL. Patients with t(11;14)(q13;q32) associated with CCND1/IGH fusion, have mantle cell lymphoma which can be distinguished from SLL and other B-cell lymphomas with this assay. Patients with t(14;18)(q32;q21) or t(14;19)(q32;q13.3) may have an atypical form of SLL or another low-grade B-cell lymphoma.

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.


A positive result is not diagnostic for small lymphocytic lymphoma, but may provide relevant prognostic information.


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 U.S. Food and Drug Administration, 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, however nonformalin-fixed samples will not be rejected.


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 62 formalin-fixed, paraffin-embedded tissue specimens from patients diagnosed with small lymphocytic lymphoma, splenic marginal zone lymphoma, or lymphoplasmacytic lymphoma and a set of 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

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

2. Shanafelt TD: Predicting clinical outcome in CLL: how and why. Hematology Am Soc Hematol Educ Program 2009;421-429

3. Van Dyke DL, Werner L, Rassenti LZ, et al: The Dohner fluorescence in situ hybridization prognostic classification of chronic lymphocytic leukaemia (CLL): the CLL Research Consortium experience. Br J Haematol 2016;173:105-113