title: Effect of Imaging Parameter Thresholds on MRI Prediction of Neoadjuvant Chemotherapy Response in Breast Cancer Subtypes.
abstract: The purpose of this study is to evaluate the predictive performance of magnetic resonance imaging (MRI) markers in breast cancer patients by subtype. Sixty-four patients with locally advanced breast cancer undergoing neoadjuvant chemotherapy were enrolled in this study. Each patient received a dynamic contrast-enhanced (DCE-MRI) at baseline, after 1 cycle of chemotherapy and before surgery. Functional tumor volume (FTV), the imaging marker measured by DCE-MRI, was computed at various thresholds of percent enhancement (PEt) and signal-enhancement ratio (SERt). Final FTV before surgery and percent changes of FTVs at the early and final treatment time points were used to predict patients' recurrence-free survival. The full cohort and each subtype defined by the status of hormone receptor and human epidermal growth factor receptor 2 (HR+/HER2-, HER2+, triple negative) were analyzed. Predictions were evaluated using the Cox proportional hazard model when PEt changed from 30% to 200% in steps of 10% and SERt changed from 0 to 2 in steps of 0.2. Predictions with high hazard ratios and low p-values were considered as strong. Different profiles of FTV as predictors for recurrence-free survival were observed in each breast cancer subtype and strong associations with survival were observed at different PEt/SERt combinations that resulted in different FTVs. Findings from this retrospective study suggest that the predictive performance of imaging markers based on FTV may be improved with enhancement thresholds being optimized separately for clinically-relevant subtypes defined by HR and HER2 receptor expression.
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States of America.
authors.forename: Wei-Ching
authors.initials: WC
authors.lastname: Lo
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States of America.
authors.forename: Wen
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States of America.
authors.forename: Ella F
authors.initials: EF
authors.lastname: Jones
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States of America.
authors.forename: David C
authors.initials: DC
authors.lastname: Newitt
authors.affiliation: Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America.
authors.forename: John
authors.initials: J
authors.lastname: Kornak
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States of America.
authors.forename: Lisa J
authors.initials: LJ
authors.lastname: Wilmes
authors.affiliation: Department of Surgery and Radiology, University of California San Francisco, San Francisco, California, United States of America.
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Esserman
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States of America.
authors.forename: Nola M
authors.initials: NM
authors.lastname: Hylton
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D054316:Biomarkers, Pharmacological / Q000032:analysis; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics / Q000401:mortality; D001952:Bridged-Ring Compounds / Q000627:therapeutic use; D003287:Contrast Media; D003520:Cyclophosphamide / Q000627:therapeutic use; D004317:Doxorubicin / Q000627:therapeutic use; D005260:Female; D015870:Gene Expression; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000379:methods*; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics / Q000401:mortality; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism; D011980:Receptors, Progesterone / Q000235:genetics / Q000378:metabolism; D012189:Retrospective Studies; D043823:Taxoids / Q000627:therapeutic use; D047368:Tumor Burden / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents; D054316:Biomarkers, Pharmacological; D001952:Bridged-Ring Compounds; D003287:Contrast Media; D003520:Cyclophosphamide; D004317:Doxorubicin; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D043823:Taxoids; C080625:taxane; C508053:ERBB2 protein, human