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Mantle cell lymphoma with MYC-R
AB
CD
Figure 3. MYC protein expression in correlation with MYC cytogenetic status in mantle cell lymphoma. (A); Comparison of median overall survival (OS) between man- tle cell lymphoma (MCL) with MYC rearrangement (MYC-R) and MYC/BCL2 double hit lymphoma (DHL): (B) All cases included; (C) Only de novo cases included; (D) Only patients who received intensive induction chemotherapy included.
is significantly related to the treatment regimens patients received and majority patients received intensive chemotherapy, we further compared the OS between patients who only received intensive induction immunochemotherapy (including R-Hyper-CVAD and R-EPOCH) in these two groups, and as shown in Figure 3D, there was no significant difference in OS between the two sub-groups.
Discussion
MYC aberrations can occur rarely in cases of MCL. In this study, we collected 88 MCL patients with known MYC status and explored the prognostic role of MYC aberrations. We show that MYC-R but not MYC-EC is an independent adverse prognostic factor in MCL patients. We also compared the clinicopathologic features of MCL patients with MYC-R, so-called double hit MCL, to a large group of patients with MYC/BCL2 DHL and show some similarities and differences. To our knowledge, this is the largest series of MCL cases in which MYC status has been assessed.
MCL with MYC-R has been reported previously, how- ever, most studies have been case reports or small case series that were mainly descriptive and without a MYC-R
control group to compare for clinicopathologic features and prognosis.6,24-29 In this study, by comparing to a control group of 61 MCL cases without MYC-R, MCL cases with MYC-R demonstrated some unique clinicopathologic fea- tures: more frequently have blastoid/pleomorphic mor- phology, more frequently express CD10, MYC, MYC and BCL2 co-expression, with a higher Ki67 proliferation rate and an inferior OS. It is well known that blastoid and pleo- morphic variants of MCL has a poorer prognosis. In order to exclude the effect of morphology, the role of MYC-R was further evaluated in blastoid/pleomorphic MCL cases, which showed MYC-R was associated with higher MYC expression and expression of CD10 and a poorer OS, especially in transformed MCL cases. However, there are many other potential factors involved when patients with MCL undergo progression or transformation. In order to further exclude other possible confounding fac- tors, a multivariate analysis was performed and demon- strated that MYC-R is an independent poor prognostic fac- tor in MCL patients.
MYC (8q24) is an essential global transcription factor that controls 10-15% of all human genes and regulates many cellular functions including cell cycle, cell growth, metabolism, biosynthesis, survival, and apoptosis. Dysregulation of MYC induces lymphomagenesis. In BL, MYC-R is the primary event and mainly translocated with
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