Evaluation of breast tumor blood flow with dynamic first-pass 18F-FDG PET/CT: comparison with angiogenesis markers and prognostic factors.

UNLABELLED

The purpose of this study was to prospectively evaluate the relationship between tumor blood flow and glucose metabolism as evaluated by dynamic first-pass (18)F-FDG PET and by proliferation and endothelial pathologic markers in the setting of newly diagnosed breast cancer.

METHODS

Forty patients were prospectively included. Biopsy samples of each tumor were used to assess the Ki67 index of proliferation and immunostaining for CD34 (a panendothelial cell marker) and CD105 (a proliferation-related endothelial cell marker). All patients underwent (18)F-FDG PET/CT at least 1 wk after sample biopsy and before any treatment. A dynamic 2-min acquisition was performed immediately after intravenous injection of a 5 MBq/kg dose of (18)F-FDG; tumor blood flow was then calculated using a single-compartment kinetic model. A static acquisition was performed 90 min after injection for quantification of delayed (18)F-FDG tumor uptake (standardized uptake value maximal index [SUV(max)]), reflecting tumor metabolism.

RESULTS

Pathologic and PET/CT data were available for all patients. The SUV(max) measured on delayed PET images correlated strongly and positively with the expression of Ki67 (r = +0.69; P < 0.0001). In contrast, there was no significant correlation between SUV(max) and endothelial markers (CD34 and CD105). Tumor blood flow correlated positively with the expression of CD34 and CD105 (P = 0.016 and P = 0.007, respectively) and with the expression of Ki67 (P = 0.028). By logistic regression analysis, only expression of Ki67 remained an independent predictor of high (supramedian) SUV(max); CD105 score and histopathologic grade 3 were independently associated with a high (supramedian) tumor blood flow level.

CONCLUSION

Tumor blood flow quantified by dynamic first-pass (18)F-FDG PET/CT is significantly associated with tumor angiogenesis as evaluated by immunohistochemistry in the setting of breast cancer, whereas tumor metabolism appears to be more associated with markers of proliferation. Thus, determination of tumor blood flow and metabolism with a single injection of (18)F-FDG could be an exciting alternative to more complex and less available techniques.