Hodgkin lymphoma response monitoring by FDG-PET explained

10-19-2006

Scientists elucidated the mechanisms by which F-18-fluoro-deoxy-D-glucose positron emission tomography (FDG-PET) monitors the effect of anti-cancer treatment in Hodgkin lymphoma patients.

"In Hodgkin's lymphoma, FDG-PET is used for staging and response evaluation after chemotherapy. However, drug-mediated downregulation of glucose uptake in viable Hodgkin's lymphoma cells might limit the use of FDG-PET. We analyzed the effect of etoposide on cell viability and uptake of F-18-fluoro-deoxy-D-glucose or the glucose analog 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxyglucose (2-NBDG) in vitro," scientists in Germany reported.

"Etoposide induced a dose-dependent cytotoxicity in HDLM-2 cells which was significantly correlated with reduced FDG uptake," explained U. Banning and colleagues, University of Leipzig. "However, it also significantly increased the portion of viable cells which did not take up 2-NBDG. Interestingly, etoposide-induced cytotoxicity was mainly mediated via caspase-dependent mechanisms, whereas the cell death induced by deprivation of glucose was mediated via caspase-independent mechanisms.

"Etoposide-mediated reduction of glucose uptake by Hodgkin's lymphoma cells is mainly caused by cell death. In a small fraction of viable cells, etoposide might downregulate glucose transporters and/or hexokinase activity and by that inhibit glucose uptake. This, however, might not lead to false-negative results of response evaluation in Hodgkin's lymphoma patients after chemotherapy, because inhibition of glucose uptake itself seems to be a strong inducer of cell death."

The researchers concluded, "Altogether, this study provides important in vitro evidence to clarify the mechanisms by which FDG-PET monitors the effect of anti-cancer treatment in Hodgkin's lymphoma patients."

Banning and colleagues published their study in European Journal of Haematology (Effect of drug-induced cytotoxicity on glucose uptake in Hodgkin's lymphoma cells. Eur J Haematol, 2006;77(2):102-108).

For additional information, contact U. Banning, University of Leipzig, Germany.

The publisher's contact information for the European Journal of Haematology is: Blackwell Publishing, 9600 Garsington Rd., Oxford OX4 2DQ, Oxon, England.

Keywords: Halle, Germany, Cancer Therapy, Chemotherapy, Cancer Drugs, Diagnostics, Diagnosis, Prognosis, Prognostics, Etoposide, Glucose Transport, Glucose Uptake, Hodgkin's Lymphoma, Oncology, Pharmaceuticals, Positron Emission Tomography, Response Evaluation, Cancer Therapy, Tumor Biology.

This article was prepared by Clinical Oncology Week editors from staff and other reports. Copyright 2006, Clinical Oncology Week via NewsRx.com.