High incidence of MYC rearrangement in human immunodeficiency virus-positive plasmablastic lymphoma

MYC rearrangements are the main cytogenetic alterations in plasmablastic lymphoma (PBL). We aimed to investigate the relationship between MYC rearrangement and the clinicopathological features of PBL.

MYC rearrangements assessed in 13 unpublished single-centre PBL cases, and an additional 85 cases from the literature, with reported MYC rearrangement information individualised by patient, were reviewed. In Asia, PBL was much less commonly diagnosed in human immunodeficiency virus (HIV)-positive patients (27% versus 84%, P = 0.000), with older age (median age at diagnosis: 52 years versus 44 years, P = 0.046) and a lower EBV infection rate (56.8% versus 81.8%, P = 0.049), than in non-Asian regions. Overall, MYC rearrangements were identified in 44 of 98 (44.9%) PBL cases, and IGH was the partner in almost all available cases (30/31, 96.8%), as confirmed with a MYC-IGH fusion probe. The MYC rearrangement rate in HIV-positive cases (33/55, 60.0%) was significantly higher than that in HIV-negative cases (11/38, 28.9%, P = 0.003). Patients with MYC rearrangement showed a trend towards an inferior median survival time (9.6 months versus 15.7 months, P = 0.122) and 2-year overall survival (17% versus 32%, P = 0.238).

MYC rearrangement was frequently identified in PBL patients, and IGH was the partner gene in an overwhelming majority of MYC rearrangements. In addition, the MYC rearrangement rate was significantly higher in HIV-positive PBL patients than that in HIV-negative patients. MYC rearrangement may play an important role in the pathogenesis of HIV-positive PBL, but further studies are required to understand the underlying mechanisms.