The effect of chemotherapy on glucose utilization in breast cancer patients: Evaluation with [18F]FDG PET/CT

Objectives The alterations of glucose metabolism and insulin resistance after chemotherapy in breast cancer patient have been issued. In this study, we aimed to investigate the effect of neoadjuvant chemotherapy on glucose utilization in women with breast cancer using [18F]FDG PET/CT.

Methods Twenty women (mean age: 44±10 yrs) who treated with neoadjuvant chemotherapy for breast cancer were retrospectively evaluated. Whole body 18F-FDG PET studies were performed before and after therapy, and mean duration of chemotherapy was 65±30 days. Patient’s weight, BMI, blood glucose and cholesterol level during chemotherapy were reviewed. As PET/CT parameters, standardized uptake value (SUV) corrected by lean body mass for skeletal muscle, fat, liver, heart was measured on FDG PET. Also, volume of total fat, visceral and subcutaneous fat at level of umbilicus on CT were measured and calculated the fat ratio (V/S ratio= visceral fat/subcutaneous fat).

Results None of clinical parameters was significantly changed in follow up PET. However, V/S ratio on CT tended to be increased after treatment (30.4±9.91 vs 31.9±10.25, P=0.12). Among the PET parameters, the FDG uptake for fat was significantly lower (meanSUV: 0.30±0.06 vs. 0.23±0.03, P<0.0001), and the uptake in the muscle was significantly higher in post compared to pre PET/CT (0.48±0.1 vs 0.52±0.1 P=0.04). Moreover, the change of FDG uptake in fat and muscle showed a tendency of correlation with the increment of V/S ratio.

Conclusions These data indicate that glucose uptake in the fat and muscle assessed by PET/CT are significantly changed after chemotherapy, and correlated with the fat deposition in the viscera possibly related with insulin resistance. We can expect FDG PET/CT can be useful tools for evaluation of insulin resistance and glucose metabolism changes during chemotherapy in cancer patients