Laboratory Lab results are too important to go anywhere else.

Plasma Cell Myeloma FISH Panel by Fluorescence In Situ Hybridization (FISH) Analysis

FISH, myeloma panel, GMYE2, genetic, p53 gene/CEP17 for 17p deletion, RB1 gene (13q14), LAMP1 gene (13q34) for monosomy 13/13q deletion, CEP3/CEP7 for detection of hyperdiploidy, CCNDI and IgH gene rearrangement, CKS1B/CDKN2C (p18) Amplification/Deletion

Test Codes

EPIC: LAB5125

Department

Cytogenetics

Specimen Collection Criteria

Collect: Bone marrow aspirate in a Dark Green-top Sodium Heparin tube. (Minimum: 1.0 mL)

A copy of the requisition must be sent with the specimen.

Physician Office/Draw Specimen Preparation

Do not freeze specimen. Maintain specimens at room temperature (20-25°C or 68-77°F) prior to courier pickup. For delays in transport (greater than 48 from the time of collection), refrigerate (2-8°C or 36-46°F) the specimen.

Preparation for Courier Transport

Transport: Bone marrow, at room temperature (20-25°C or 68-77°F) or refrigerated (2-8°C or 36-46°F).

Rejection Criteria

Specimens arriving in the Laboratory 4 days or more following the original collection date.

Fixed or frozen specimens. 

In-Lab Processing

Specimens are processed immediately upon receipt in the Laboratory.

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 48 hours
Refrigerated (2-8°C or 36-46°F): 96 hours
Frozen (-20°C/-4°F or below): Unacceptable

Specimen Storage in Department Prior to Disposal:

Refrigerated (2-8°C or 36-46°F): 7 days. A backup cell pellet is maintained for three weeks after the final report has been issued.

Laboratory

Royal Oak Cytogenetics Laboratory

Performed

Monday – Friday, 8:00 am – 5:00 pm.
Results available within 7 days of receipt in the Laboratory.

Reference Range

Positive or negative for a neoplastic clone. An interpretative report will be provided.

Test Methodology

Fluorescence In Situ Hybridization (FISH) Analysis.

Interpretation

Loss of chromosome 13/13q- is associated with shorter survival, lower response rates to treatment, and is considered an independent prognostic variable. Gain of chromosomes 3 and 7 is found in >90% of hyperdiploid cases. Hyperdiploid PCM patients seem to have a better outcome than nonhyperdiploid patients. Four major specific IgH translocations, t(11;14)(q13;q32), t(4;14)(p16.3;q32), (14;16)(q32;q23), and t(14;20)(q32;q12) are identified in PCM. The t(4;14), t(14;16), and t(14;20) are cryptic translocations found in less than 15% of patients and can only be detected accurately utilizing the FGFR3/IgH, MAF/IgH, and MAFB/IgH FISH dual fusion FISH probes, respectively (which can be performed reflexively). Both the t(4;14) and t(14;16) are associated with hypodiploidy, an adverse disease outcome with shorter survival, and aggressive clinical features. The t(11;14) is associated with a favorable prognosis. Deletion of 17p13 (p53 gene) also confers a negative risk factor in PCM. Amplification (upregulation) of the CKS1B gene is associated with disease progression and a poorer prognosis, as is deletion of the tumor suppressor gene CDKN2C.

Clinical Utility

Conventional cytogenetic analysis in plasma cell myeloma (PCM) is difficult due to patchy bone marrow infiltration and low proliferation of the malignant plasma cells. An abnormal karyotype is found in 30-40% of cases, more often in advanced stages than in newly diagnosed patients. Two distinct cytogenetics groups are recognized: a hyperdiploid group with 47 chromosomes or greater observed in around 60% of cases and a nonhyperdiploid group with 46 chromosomes or less, observed in the remaining 40%. Nonhyperdiploid PCM has a higher prevalence of IgH/14q32 translocations, monosomy 13/13q deletion, and 17p deletion. Clinically, this cytogenetics classification is valuable, since FISH analysis has demonstrated that chromosome aberrations can be found in the majority of PCM cases. This myeloma FISH panel includes enumeration probes for chromosomes 3 and 7 to screen for ploidy, as well as probes to detect monosomy 13/13q deletion, p53 gene deletion, and common IgH translocations. This methodology yields significant prognostic information for risk assessment and treatment stratification in patients with PCM.

Guidelines for Cytogenetic/Molecular Follow-Up Testing of Hematopoietic Malignancy

Reference

1. Dewald GW et al. (2005) Relationship of patient survival and chromosome anomalies detected in metaphase and/or interphase cells at diagnosis of myeloma. Blood 106(10), 3553-3558.

CPT Codes

88271x10 (DNA probe, each), 88275x6 (Interphase analysis, 100-300 cells).

Contacts

Last Updated

12/30/2022