Background: Positron emission tomography (PET) with 2-deoxy-2-fluoro[18F]-D-glucose (FDG) can provide quantitative information about tumor glucose metabolism. The prognostic value of this technique was evaluated for breast carcinoma patients.
Methods: FDG PET was performed on 70 patients with primary breast carcinoma, and the differential absorption ratio (DAR) was calculated as an index of FDG uptake. Overall and relapse free survival curves were created by the Kaplan-Meier method, and differences between the curves were analyzed with the log rank test. For multivariate analysis, the Cox proportional hazards regression model was used.
Results: The mean DAR was 2.61+/-1.61 standard deviation (range, 0.65-9.39). According to the grade of DAR, patients were then classified into high DAR (> or =3.0) and low DAR (<3.0) groups. The high DAR group had significantly worse prognoses for both overall and relapse free survival (P < 0.0005 and P < 0.0001, respectively). In multivariate analysis, DAR was an independent predictor of the relapse free survival of breast carcinoma patients (P=0.0377).
Conclusions: DAR, as determined by FDG PET, may be useful as a prognostic indicator for patients with primary breast carcinoma.