Changes in glucose metabolism of the brain after immunochemotherapy in patients with diffuse large B-Cell lymphoma on fluorodeoxyglucose positron emission tomography/computed tomography

Objective: Mild cognitive impairment seen after chemotherapy is called chemo brain. Neuropsychological tests mainly diagnose chemo brain, but morphological or functional imaging modalities may also contribute to the diagnosis. This study aimed to examine the change in brain fluorodeoxyglucose (FDG) uptake after immunochemotherapy in patients with diffuse large B-cell lymphoma (DLBCL). Materials and Methods: FDG positron emission tomography/computed tomography images performed for both staging and treatment response evaluation of patients treated with R-CHOP for DLBCL were retrospectively analyzed. It was investigated whether the FDG uptake of the brain decreased after the treatment. Results: There was no significant decrease in FDG uptake in the brain regions of 40 patients treated with R-CHOP compared to pretreatment. There was no significant change in brain FDG uptake after treatment between Ann Arbor Stage 1 or Stage 2 patients and Ann Arbor Stage 3 or Stage 4 patients compared to pretreatment. There was no significant change in brain FDG uptake after treatment compared to pretreatment between patients with Deauville score (DS) 1–3 and patients with DS 4 or 5 according to treatment responses. Patients with the most hypermetabolic lesion SUVmax >30.5 had significantly decreased posttreatment SUVmean in the right basal ganglia, left and right central regions, left cingulate and paracingulate cortices, right striatum, left and right frontal cortices, left occipital cortex, left and right parietal cortices, left and right precunei, and right temporal cortex. Conclusion: FDG uptake decreased in many brain regions after R-CHOP in patients with DLBCL whose lesions showed high FDG uptake.