Early On-therapy PET at First-line Treatment in Diffuse Large B-cell Lymphoma Stage IIB-IV

Title: Evaluation of response to treatment using 18F-FDG positron emission tomography imaging (PET) in diffuse large B-cell lymphoma stage IIB-IV with special emphasize on the prognostic significance of early on-therapy PET at first-line treatment Study design: Multicenter trial. Planned sample size: 100 patients. Number of centers: Denmark 2; Sweden 1; Norway 1; Finland 1. Aim of the study: 1. To evaluate the prognostic significance of PET early after treatment initiation. 2. To compare early PET with standard response criteria for NHL and the International Prognostic Index (IPI) in the prediction of response and outcome. Primary objective: The prognostic significance of FDG-PET after 1 cycle of chemotherapy. End-points: Progression-free survival (PFS). Overall survival (OS). Response to treatment (standardized response criteria) at mid-treatment and post-treatment. Inclusion criteria: Age ≥ 18 years. Newly diagnosed consecutive patients with diffuse large B-cell lymphoma (DLBCL) according to the WHO classification. Ann Arbor stage IIB-IV. Written informed consent. Exclusion criteria: Previously treated with chemotherapy or irradiation. Previous malignant diagnosis except basal cell carcinoma and cervical carcinoma in situ. Pregnancy. Lactation. Diabetes mellitus. Extreme adipositas. Claustrophobia. Active inflammatory disease or infection. PET-CT evaluation: PET and CT at primary staging before initiation of therapy and PET after one cycle of intravenous chemotherapy (day 10-20) are mandatory. The results of the PET scans are blinded and will not be available for the local physicians. If the PET result is opened, the patient will be excluded from the study. Only post-treatment PET scans are allowed outside the protocol. The local physician may use post-treatment PET in diagnostic or therapeutic considerations. Only dedicated full-ring PET scanners are allowed in this study. Treatment: Therapy with a CHOP-like backbone according to local standards of the individual centers. Treatment according to other protocols allowed.