The realMIND study is a multicenter, observational study intended to further characterize the safety and effectiveness data of US patients (with a focus on racial and ethnic minority patients) with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL), treated with tafasitamab in combination with lenalidomide.

This observational study is intended to further characterize the safety and effectiveness of tafasitamab, in combination with lenalidomide, in patients with R/R DLBCL in the US, with a focus on racial and ethnic minorities.

This study also characterizes the overall treatment patterns (e.g., line of treatment, dose modification, combination partners, use as monotherapy) of US patients with R/R DLBCL who have been treated with tafasitamab with a focus on racial and ethnic minorities This multicenter real-world study will help to characterize the use of tafasitamab (e.g., line of treatment, dose modification, combination partners, use as monotherapy) among US patients with R/R DLBCL with a focus on racial and ethnic minorities This is an observational study; as such, no study visits or assessments, laboratory tests or procedures are mandated by the study. Patients will be evaluated and treated according to the physician's usual practice and discretion.

Patient data for this observational study will be collected in one of two ways; either

• by prospective follow-up of patients included at study sites, or
• by retrospective collection of data from patient records, at study sites or from vendor databases.

Criteria: Inclusion Criteria:

1. Age ≥18 years at the time of diagnosis of R/R DLBCL

2. Initiated or initiating tafasitamab treatment

3. R/R DLBCL patients who have received at least one (1) prior line of treatment for DLBCL

4. Histologically confirmed DLBCL such as:

   a) DLBCL not otherwise specified (NOS) b) T-cell histiocyte-rich large B-cell lymphoma (THRLBCL) c) Epstein-Barr virus (EBV)-positive DLBCL of the elderly d) Composite lymphoma with a DLBCL component with a subsequent DLBCL relapse, according to Revised European American Lymphoma (REAL)/World Health Organization (WHO) classification e) Patients with evidence of histological transformation to DLBCL from an earlier diagnosis of low-grade lymphoma (i.e., an indolent pathology such as follicular lymphoma [FL], marginal zone lymphoma [MZL], chronic lymphocytic leukemia [CLL]) with a subsequent DLBCL relapse f) High-grade B-cell lymphoma: i) DLBCL with MYC and BCL2 or BCL6 translocation (double-hit) and MYC and BCL2 and BCL6 translocations (triple-hit) ii) High-grade B-cell lymphoma, NOS

5. Signed and dated ICF by the patient or the patient's Legally Acceptable Representative (LAR), for patients with prospective data collection, as applicable. For deceased or otherwise unreachable patients, no informed consent will be obtained for data collection in the study, provided that the competent Independent Ethics Committee (IEC)/Institutional Review Board (IRB) has provided favorable opinion and that any other local regulatory requirements on this matter are met

Exclusion Criteria:

• Initiated or initiating tafasitamab treatment in the context of an interventional study.

Community Study- 40 sites across the USA