Evaluation of decreased uptake of 18F-fluorodeoxyglucose in the cerebral cortex of patients with intracranial non-Hodgkin's lymphoma lesions through PET/CT.
BACKGROUND
This study aims to investigate whether basal ganglia can be utilised as reference for measuring ratios between standardised uptake values (SUV), namely, SUVmaxand SUVmean, of 18F-fluoro-deoxyglucose (18F-FDG) uptake, in the ipsilateral cerebral cortex and basal ganglia of patients with non-Hodgkin's lymphoma lesions.


METHODS
Fifty-three patients with pathologically confirmed highly metabolic non-Hodgkin's lymphoma were retrospectively analysed; these patients were subjected to treatment strategy and underwent positron emission tomography/computed tomography (PET/CT). Nineteen of the patients who improved after the treatment were re-examined by PET/CT. PET/CT simultaneity was performed on 12 normal volunteers as the control group. SUVmaxand SUVmeanin the cerebral cortex and basal ganglia (head of caudate nucleus and lenticular nucleus) were evaluated by ganglia was also calculated. The ratios were compared between patients and the control group as well as before and after the treatment.


RESULTS
The ratios between the SUVmaxof 18F-FDG uptake were 1.03±0.16 (range 0.50-1.51, left) in the ipsilateral cerebral cortex and 1.02±0.16 (range 0.50-1.31, right) in the basal ganglia of 53 patients with non-Hodgkin's lymphoma; the corresponding ratios in the 12 controls were 1.09±0.11 (range 0.99-1.21, left) and 1.09±0.09 (range 1.00-1.24, right), respectively. The ratios between the SUVmeanand 18F-FDG uptake in the ipsolateral cerebral cortex and basal ganglia were 0.76±0.09 (range 0.50-1.07, left) and 0.76±0.09 (range 0.48-0.98, right), respectively, which were lower than those in the control group [0.93±0.06 (range 0.83-0.99, left) and 0.92±0.05 (range 0.84-0.99, right), respectively]. For patients effectively treated, the ratios between the SUVmaxin the ipsolateral cerebral cortex and basal ganglia were 1.08±0.13 (range 0.94-1.36, left) and 1.08±0.13 (range 0.88-1.31, right) before the treatment; these values were similar to 1.11±0.13 (range 0.85-1.36, left) and 1.09±0.11 (range 0.90-1.32, right) obtained in the ipsolateral cerebral cortex and basal ganglia of the patients after the treatment, respectively. The ratios between the SUVmeanin the ipsolateral cerebral cortex and basal ganglia were 0.78±0.06 (range 0.68-0.93, left) and 0.78±0.06 (range 0.69-0.95, right) in the patients before the treatment; these ratios were lower than those in post-treatment patients [0.90±0.06 (range 0.74-1.00, left) and 0.90±0.07 (range 0.72-1.00, right), respectively], respectively.


CONCLUSIONS
High levels of 18F-FDG metabolism in patients with non-Hodgkin's lymphoma may decrease glucose uptake in the cerebral cortex (diversion of 18F-FDG from the cerebral tissue to the lymphoma tissue); this phenomenon may be reversed with effective therapy for lymphoma. The ratio with 18F-FDG metabolism in basal ganglia could be used as reference to quantify and monitor glucose metabolism in cerebral tissues during the course of lymphoma.
Department of PET-CT, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Qingbo
Q
Zhang
Department of Geriatric hematology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Tian
T
Tian
Department of Internal Medicine, Nanjing First Hospital Affiliated to Nanjing Medical University, Nanjing, China.
Li
L
Wang
Department of Geriatric hematology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Hongxia
H
Qiu
Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China. Electronic address: llddyy1976@126.com.
Danming
D
Li
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001479:Basal Ganglia / Q000000981:diagnostic imaging / Q000473:pathology; D002540:Cerebral Cortex / Q000000981:diagnostic imaging* / Q000473:pathology; D002648:Child; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D000072078:Positron Emission Tomography Computed Tomography; D055815:Young Adult
D019788:Fluorodeoxyglucose F18
(18)FDG-PET; Cerebral cortex; Non-Hodgkin’s lymphoma