<qa>  What is the sensitivity of the DLBCL?- Histologically confirmed DLBCL, expressing CD20. Sufficient diagnostic material should be available to forward to Haematological Malignancies Diagnostic Service HMDS for gene expression profiling and central pathology review. Core biopsies are acceptable, however the molecular profiling success rate is inferior compared to larger surgically acquired tissue samples. Best diagnostic practice encourages investigators to seek the latter approach whenever clinically appropriate. 