Prognostic value of FDG-PET and DWI in breast cancer

To investigate the prognostic value of preoperative FDG-PET/CT and diffusion weighted imaging (DWI) in patients with breast cancer. A total of 73 patients with newly diagnosed invasive breast cancer who had undergone preoperative whole-body FDG-PET/CT and 3-Tesla breast MRI including DWI followed by surgery were identified. Effects of primary tumor PET parameters [maximum standardized uptake value (SUVmax), mean SUV (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG)] and DWI parameters [mean apparent diffusion coefficient (ADC(mean)) and minimum ADC (ADC(min))] including clinicopathologic factors on disease-free survival (DFS) were retrospectively evaluated using the log-rank and Cox methods. After a median overall follow-up of 32.3 months in all patients, 6 (8.2%) of the 73 patients had recurrence. Receiver operating characteristic curve analysis and log-rank tests showed that patients with a high primary tumor SUVmax (>= 3.60), MTV (>= 3.15), and TLG (>= 16.0) had a significantly lower DFS rate than those with a low SUVmax (< 3.60), MTV (< 3.15), and TLG (< 16.0), respectively (p = 0.0054, p = 0.0054, and p < 0.0001, respectively). SUVmean, ADC(mean), and ADC(min) were not significantly associated with recurrence. Univariate analysis showed that SUVmax (p = 0.0054), MTV (p = 0.0054), TLG (p < 0.0001), tumor size (p = 0.0083), estrogen receptor negativity (p = 0.046), progesterone receptor negativity (p = 0.0023), human epidermal growth factor receptor 2 positivity (p = 0.043), and the presence of axillary lymph node metastasis (p = 0.0037) were also significantly associated with recurrence. However, in multivariate analysis, none of them were an independent factor. The preoperative SUVmax, MTV, and TLG of primary breast cancer are prognostic factors for recurrence, whereas ADC values are not.