Page 211 - Haematologica May 2020

Impact of MYC increased copy number in DLBCL
and these constituted our study cohort. Figure 2 shows the flow diagram of the entire study population. The patients’ main clinical characteristics at diagnosis are presented in Table 1, both for the whole cohort with FISH abnormali- ties and for the subgroups with either structural or numer- ical MYC aberrations. In addition, MYC protein expression by immunostaining was available for 52 patients, and was positive in 88%: among them, all patients with a transloca- tion of MYC (MYC-T) over-expressed the MYC protein, whereas seven patients with numerical aberrations of MYC (11%) showed <40% expression of MYC protein by
IHC. Five patients initially considered fit for curative ther- apy received palliative/symptomatic treatment and were therefore excluded from the survival analyses. The remain- ing 90 patients received immuno-chemotherapy: standard dose in 46 patients or intensified regimens in 44 patients. Twenty-three patients received ASCT as intensification of first-line treatment. Median follow up was 38 months (range 0-79). A complete response (CR) was achieved in 55 patients (61%). Overall, there was no difference in achievement of CR between patients receiving intensified and those receiving standard treatment (57% vs. 65%,
Figure 1. Numerical aberra- tions of MYC by fluores- cence in situ hybridization (FISH). (A and B) Thin white arrows show MYC increased copy number (MYC-ICN); white thick arrow shows MYC wild type. (C and D) Thin white arrows show MYC amplification (MYC-AMP).
Figure 2. Flow-chart of the study cohort and fluo- rescence in situ hybridization (FISH) results. results. MYC-T SH: MYC translocated single-hit dif- fuse large B-cell lymphoma (DLBCL); MYC-T DH: MYC/BCL2 or MYC/BCL6 translocated double-hit DLBCL; MYC-T TH: MYC/BCL2/BCL6 translocated triple-hit DLBCL; MYC-ICN ≤4: increased copy num- ber of MYC ≤4; MYC-ICN >4: increased copy num- ber of MYC >4; MYC-AMP: MYC amplification. n: number.
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