BCL6 (3q27.3) Gene Rearrangement Test Cost & Procedure

In diffuse large B-cell lymphoma, a cancer marked by genetic variety and a wide variation in clinical prognosis, BCL6 gene rearrangement is the most common chromosomal aberration.

One of the most prevalent non-random abnormalities in non-lymphomas Hodgkin's (NHL), particularly the diffuse, large cell type, is chromosomal alterations affecting 3q27. Recently, it was shown that BCL6 rearrangement was associated with frequent extranodal lesions, infrequent bone marrow infiltration, and a positive clinical outcome.

A heterogeneous collection of tumours, diffuse large B-cell lymphomas (DLBCL) differ in cellular composition, phenotype, cytogenetics, place of presentation, and disease natural history. While standard chemotherapy can cure about half of DLBCL patients, the remaining patients will pass away from their illness. A crucial first step in creating novel treatment plans is identifying patients who are not likely to respond to standard therapy at the time of presentation. The International Prognostic Index (IPI) (Shipp et al., 1993) is currently the most useful tool for identifying prognostic subgroups and is based on age, Ann Arbor Stage, number of extranodal sites, performance status (according to the Eastern Cooperative Oncology Group (ECOG) scale), and serum lactate dehydrogenase (LDH), all of which are independent risk factors.

Methodology

• Fluorescence in situ hybridization is the method used (FISH)
• Time to complete: 3-5 days

 Prerequisites for Specimens

•  F BCL6- 5 mL of peripheral blood in heparin sodium 3mL of sodium heparin-infused bone marrow sterile centrifuge tube with fixed cytogenetically prepared cells with pellet visible in 3:1, Acetic Acid:Methanol For FISH analysis,
• FP BCL6 FFPE tissue is suitable. 10% neutral buffered formalin is the preferred fixative. Often, decalcified or B5-fixed tissues are not appropriate for FISH. It works effectively to mount tumour slices that are 3–5 m thick on positively charged organosilane coated (silanized) slides. Request a number of uncolored sections (two for each probe) and one slide with H and E stained slide.

Storage & Handling

Specimens may be transported on chilled gel packs, however temperatures during transit range from 4°C to 25°C. Keep the gel pack away from the specimen at all times. Avoid freezing. Avoiding extreme temperatures is advised.

Reference Range

The results of FISH show whether rearrangement is occurring or not. Two fusion signals (orange/green or yellow) that signify two intact copies of chromosomes can be seen in a healthy cell.