Approach to diagnosing HGBCL. Lymphomas that potentially fall into the HGBCL categories can have high-grade (blastoid or intermediate [between BL and large-cell]) morphology or resemble DLBCL. Tumors with morphology resembling BL and other HGBCL are assigned to the provisional entity LBCL with 11q aberration (LBCL-11q) if they lack MYC rearrangement and have 11q aberration. The full morphological spectrum of cases with this aberration requires further study. Other cases in this category present with large-cell morphology. Tumors should not be assigned to LBCL-11q if they harbor concurrent MYC and BCL2 or MYC and BCL6 rearrangements. Tumors with morphology resembling BL and an immunophenotype consistent with BL, lacking both MYC rearrangement and 11q aberration, are likely diagnosed as HGBCL, NOS, acknowledging that rare MYC rearrangements cryptic to FISH have been observed.