FISH, AML/MDS, CEP8, Trisomy 8

Test Code

16669

CPT Codes
88271, 88275

Preferred Specimen

3 mL bone marrow or 5 mL whole blood collected in sodium heparin (green-top) tube

Minimum Volume

1 mL bone marrow • 3 mL whole blood

Other Acceptable Specimens

Bone marrow or whole blood collected in: sodium heparin (royal blue-top) tube, or sodium heparin lead-free (tan-top) tube • Bone marrow in culture transport media

Instructions

Clinical history and reason for referral are required with test order. Prior therapy and transplant history should be provided with test order.
Bone marrow 1-3 mL, or whole blood 3-5 mL. Green Vacutainer (sodium heparin only). Dark/royal blue or tan-top sodium heparin tubes are acceptable containers for this test. Ship at room temperature. Bone marrow transport medium is available upon request.

Specimen viability decreases during transit. Send specimen to testing lab for viability determination. Do not freeze. Do not reject.

If results are not possible, the test order may be canceled and replaced with a Cytogenetics Communication.

Transport Temperature

Room temperature

Specimen Stability

Room temperature: See instructions
Refrigerated: See instructions
Frozen: See instructions

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Received frozen

Methodology
Fluorescence in situ Hybridization (FISH)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Daily; Report available: 5 days

Reference Range

See Laboratory Report

Clinical Significance

This test uses fluorescence in situ hybridization (FISH) to detect trisomy 8 in patients with myeloid disorders. This FISH test may be used to aid standard cytogenetic testing to increase the detection rate of trisomy 8 when the result of standard cytogenetic testing is uncertain or when the specimen is suboptimal [1,2]. Identification of trisomy 8 in patients with myeloid disorders may inform prognosis and aid in follow-up testing to monitor treatment outcomes [3-5].

Trisomy 8 is a common abnormality in patients with myeloid disorders, such as chronic myeloid leukemia (CML), acute myeloid leukemia (AML), myeloproliferative neoplasms (MPNs), myelodysplastic syndromes (MDS), and hematologic disorders not otherwise specified. Trisomy 8 is the most common numerical aberration in AML and the second-most common in MDS [3]. As a sole abnormality, trisomy 8 is associated with an intermediate prognosis in patients with AML [4]. In patients with MDS, trisomy 8 is also associated with an intermediate prognosis according to the Revised International Prognostic Scoring System (IPSS-R) [5]. Note that in the absence of defining morphological criteria, trisomy 8 is not considered definitive evidence of a hematologic neoplasm [6].

Although trisomy 8 is strongly associated with myeloid malignancies, it is not specific for myeloid disorders. Trisomy 8 has been found in many other neoplastic disorders, such as lymphomas, lymphoblastic leukemias, desmoid tumors, and Dupuytren contracture [3]. In addition, myeloid disorders often harbor many recurring cytogenetic aberrations other than trisomy 8. Thus, this assay does not serve as a stand-alone test for myeloid disorders [1].

The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.

References
1. CEP 8 SpectrumOrange DNA probe kit. Package insert. Abbott; 2012. Accessed April 3, 2022.
2. Jenkins RB, et al. Blood. 1992;79(12):3307-3315.
3. Paulsson K, Johansson B. Pathol Biol (Paris). 2007;55(1):37-48.
4. Hemsing AL, at al. Expert Rev Hematol. 2019;12(11):947-958.
5. Greenberg PL, et al. Blood. 2012;120(12):2454-2465.
6. Swerdlow S, et al, eds. WHO Classification of Tumors of Haematopoietic and Lymphoid Tissues. Vol 2. 4th ed. IARC Press; 2017:104.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.