Observational prospective study. Patients with DLBCL and HGBCL will be enrolled in the study to collect samples for developing a blood based assay allowing biomarker driven treatment in the future.

The rationale of this study is that, due to the lack of successful salvage options, first-line treatment outcome needs to be improved. To make this possible, a crucial condition is optimal identification of patients that will not be cured on R-CHOP. The aim of this protocol is to develop new tools to monitor treatment response and disease outcome. Molecular monitoring of treatment response through liquid biopsies (LB) is such a promising new tool.

The primary objective is to collect liquid biopsy samples of patients with newly diagnosed DLBCL/HGBCL to develop a blood based assay allowing biomarker driven treatment in the future.

The secondary objectives are to collect clinical data and pre-treatment tissue samples (for determining molecular profiles) to allow for correlation to the blood based assay.

This study is designed for patients with newly diagnosed DLBCL and HGBCL ≥ 18 yr.

Inclusion Criteria:

• Patients diagnosed with newly diagnosed DLBCL (including HGBCL- NOS and HGBCL-DH) according to WHO classification 2016
• Ann Arbor stage II-IV
• Patients intended to be treated with 6 cycles R-CHOP (or DA-EPOCH-R) as first-line treatment (successive inclusion in HOVON 151 or HOVON 152 is possible)
• Age ≥ 18 years

Exclusion Criteria:

- Patients with limited stage I, II disease planned to receive 3 cycles of R-CHOP + radiotherapy, or 4 x R-CHOP+ 2R

Patients who meet the eligibility criteria