PURPOSE: To investigate combined MRI and 18F-FDG PET for assessing breast tumor metabolism/perfusion mismatch and predicting pathological response and recurrence-free survival (RFS) in women treated for breast cancer. METHODS: Patients undergoing neoadjuvant chemotherapy (NAC) for locally-advanced breast cancer were imaged at three timepoints (pre, mid, and post-NAC), prior to surgery. Imaging included diffusion-weighted and dynamic contrast-enhanced (DCE-) MRI and quantitative 18F-FDG PET. Tumor imaging measures included apparent diffusion coefficient, peak percent enhancement (PE), peak signal enhancement ratio (SER), functional tumor volume, and washout volume on MRI and standardized uptake value (SUVmax), glucose delivery (K1) and FDG metabolic rate (MRFDG) on PET, with percentage changes from baseline calculated at mid- and post-NAC. Associations of imaging measures with pathological response (residual cancer burden [RCB] 0/I vs. II/III) and RFS were evaluated. RESULTS: Thirty-five patients with stage II/III invasive breast cancer were enrolled in the prospective study (median age: 43, range: 31-66 years, RCB 0/I: N = 11/35, 31%). Baseline imaging metrics were not significantly associated with pathologic response or RFS (p > 0.05). Greater mid-treatment decreases in peak PE, along with greater post-treatment decreases in several DCE-MRI and 18F-FDG PET measures were associated with RCB 0/I after NAC (p < 0.05). Additionally, greater mid- and post-treatment decreases in DCE-MRI (peak SER, washout volume) and 18F-FDG PET (K1) were predictive of prolonged RFS. Mid-treatment decreases in metabolism/perfusion ratios (MRFDG/peak PE, MRFDG/peak SER) were associated with improved RFS. CONCLUSION: Mid-treatment changes in both PET and MRI measures were predictive of RCB status and RFS following NAC. Specifically, our results indicate a complementary relationship between DCE-MRI and 18F-FDG PET metrics and potential value of metabolism/perfusion mismatch as a marker of patient outcome.

• Klíčová slova
• Chemotherapy response, Diffusion weighted MRI, Dynamic 18F-FDG PET, Dynamic contrast enhanced MRI, Recurrence,
• MeSH
• dospělí MeSH
• fluorodeoxyglukosa F18 terapeutické užití   MeSH
• lidé MeSH
• magnetická rezonanční tomografie metody   MeSH
• nádory prsu * diagnostické zobrazování   farmakoterapie   MeSH
• neoadjuvantní terapie metody   MeSH
• pozitronová emisní tomografie metody   MeSH
• prospektivní studie MeSH
• radiofarmaka terapeutické užití   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• fluorodeoxyglukosa F18 MeSH
• radiofarmaka MeSH

PURPOSE: This study evaluated the ability of 18F-Fluorodeoxyglucose (FDG) and 18F-Fluorothymidine (FLT) imaging with positron emission tomography (PET) to measure early response to endocrine therapy from baseline to just prior to surgical resection in estrogen receptor positive (ER+) breast tumors. METHODS: In two separate studies, women with early stage ER+ breast cancer underwent either paired FDG-PET (n = 22) or FLT-PET (n = 27) scans prior to endocrine therapy and again in the pre-operative setting. Tissue samples for Ki-67 were taken for all patients both prior to treatment and at the time of surgery. RESULTS: FDG maximum standardized uptake value (SUVmax) declined in 19 of 22 lesions (mean 17% (range -45 to 28%)). FLT SUVmax declined in 24 of 27 lesions (mean 26% (range -77 to 7%)). The Ki-67 index declined in both studies, from pre-therapy (mean 23% (range 1 to 73%)) to surgery [mean 8% (range < 1 to 41%)]. Pre- and post-therapy PET measures showed strong rank-order agreement with Ki-67 percentages for both tracers; however, the percent change in FDG or FLT SUVmax did not demonstrate a strong correlation with Ki-67 index change or Ki-67 at time of surgery. CONCLUSIONS: A window-of-opportunity approach using PET imaging to assess early response of breast cancer therapy is feasible. FDG and FLT-PET imaging following a short course of neoadjuvant endocrine therapy demonstrated measurable changes in SUVmax in early stage ER+ positive breast cancers. The percentage change in FDG and FLT-PET uptake did not correlate with changes in Ki-67; post-therapy SUVmax for both tracers was significantly associated with post-therapy Ki-67, an established predictor of endocrine therapy response.

• Klíčová slova
• Aromatase inhibitors, ER+ breast cancer, FDG-PET, FLT-PET, Ki-67,
• MeSH
• antigen Ki-67 metabolismus   MeSH
• dideoxynukleosidy terapeutické užití   MeSH
• dospělí MeSH
• fluorodeoxyglukosa F18 terapeutické užití   MeSH
• inhibitory aromatasy terapeutické užití   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mastektomie MeSH
• nádorové biomarkery metabolismus   MeSH
• nádory prsu diagnostické zobrazování   farmakoterapie   metabolismus   chirurgie   MeSH
• neoadjuvantní terapie MeSH
• pozitronová emisní tomografie MeSH
• radiofarmaka terapeutické užití   MeSH
• receptory pro estrogeny metabolismus   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• alovudine MeSH Prohlížeč
• antigen Ki-67 MeSH
• dideoxynukleosidy MeSH
• fluorodeoxyglukosa F18 MeSH
• inhibitory aromatasy MeSH
• nádorové biomarkery MeSH
• radiofarmaka MeSH
• receptory pro estrogeny MeSH