| De novo DLBCL | DLBCL with no underlying indolent lymphoma |
| Transformed DLBCL | DLBCL with a history of antecedent indolent lymphoma |
| Composite DLBCL | DLBCL with indolent lymphoma in the same anatomic location |
| Discordant DLBCL | DLBCL with indolent lymphoma in a separate anatomic location |