Abstract
The occurrence of MYC-negative Burkitt lymphoma (BL) has been discussed for many years. The real frequency of the MYC insertion in MYC-negative BL is still unknown. Fine-needle aspiration biopsies of 108 consecutive patients with clinicopathologically suspected BL (suspBL) were evaluated by flow cytometry, classical cytogenetics, and fluorescence in situ hybridization (FISH). We found 12 cases (11%) without the MYC rearrangement by FISH with a MYC breakapart probe: two patients (1.9%) with cryptic MYC/IGH fusion (finally diagnosed as BL) and 10 patients (9.3%) with 11q gain/loss (finally diagnosed as Burkitt-like lymphoma with 11q aberration). The exact breakpoints of the cryptic MYC/IGH were investigated by next-generation sequencing. The MYC insertions' breakpoints were identified in PVT1 in the first case, and 42 kb upstream of 5'MYC in the second case. To date, a molecular characterization of the MYC insertion in BL has only been reported in one case. Detailed descriptions of our MYC insertions in a routinely and consecutively diagnosed suspBL cohort will contribute to resolving the issue of MYC negativity in BL. In our opinion, the presence of the MYC insertions in BL and other lymphomas might be underestimated, because routine genetic diagnostics are usually based on FISH only, without karyotyping.
Highlights
Burkitt lymphoma (BL) is a highly aggressive B-cell lymphoma and the fastest-growing human tumor type
Clinicopathological features and the results of HP/IHC revealed 108 patients with suspected BL (suspBL) diagnosis from a total cohort of approximately 11,000 flow cytometry (FCM)/CC/fluorescence in situ hybridization (FISH) diagnoses of lymphomas obtained by fine needle aspiration biopsy (FNAB) material
In our cohort of 108 cases with the clinicopathological features of BL, which accounted for approximately 1% (108/11,000) of all FNAB/FCM diagnosed lymphomas, we found 12 cases without MYC rearrangement (MYCR) as confirmed by CC and FISH with the MYC BAP probe
Summary
Burkitt lymphoma (BL) is a highly aggressive B-cell lymphoma and the fastest-growing human tumor type. The genetic hallmark of BL is MYC rearrangement (MYCR). This aberration is present in most BL cases, mainly as a result of the chromosomal translocation t(8;14)(q24; q32), and less often due to the variant translocation t(2;8)(p11;q24) or t(8;22)(q24;q11) [1–3]. The molecular consequence of these translocations is the deregulated expression of the MYC oncogene. The overexpression arises as a result of the juxtaposition of MYC to the enhancer.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have