Clinicopathological prognostic factors of 24 patients with B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma.

B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma (iBL/DLBCL), is a rare, but an aggressive subtype. In iBL/DLBCL, clinicopathological prognostic factors, including MYC and BCL2 translocations (double hit translocation, DHT) and the expression of both MYC and BCL2 (double hit score 2, DHS2), have not been studied thoroughly. We retrospectively analyzed the prognostic impact of clinicopathological factors, including MYC split, IGH/BCL2 fusion, MYC and BCL2 expressions, in 24 iBL/DLBCL patients (median age: 47 years). Fifteen patients (62 %) underwent intensive chemotherapy, and nine patients (38 %) underwent rituximab-cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP). The 5-year progression-free (PFS) and overall survival (OS) rates of intensive chemotherapy and R-CHOP were 57 and 72 %, respectively. PFS was significantly shorter in patients with high IPI score (P < .0001), stage IV (P = .001), aged ≥60 years (P = .042), IGH/BCL2 fusion (P = .029), DHS2 (P = .015), and DHT (P = .03). OS was significantly shorter in patients with high IPI score (P < .0001) and aged ≥60 years (P = .008). In iBL/DLBCL, IGH/BCL2 fusion, DHS2, and DHT were pathological prognostic factors for poor PFS, while IPI remained as more predictive for PFS and OS.