title: Complexity of Response Evaluation During Primary Systemic Therapy of Breast Cancer: Scoring Systems and Beyond-Preliminary Results.
abstract: BACKGROUND
  Precise and standardized response evaluation enables clinicians to tailor primary systemic therapy (PST).
  
  
  METHODS
  Breast cancer patients underwent (18)F-fluoro-deoxy-glucose positron emission tomography and computerized tomography (FDG-PET/CT) before and after PST. Response was assessed by maximal Standardized Uptake Value (SUVmax); morphological changes and Ki-67 labeling index (LI). In parallel response assessment was performed by European Organization for Research and Treatment of Cancer (EORTC); PET Response Criteria in Solid Tumors (PERCIST); World Health Organization (WHO); Response Evaluation Criteria in Solid Tumors (RECIST); Chevallier and Sataloff classifications, and by a novel Ki-67 score. Accuracy of different scoring systems was evaluated.
  
  
  RESULTS
  In the 42 enrolled patients, SUVmax, size, and Ki-67 LI decreased significantly on PST. Significant differences between patients with versus those without pathological complete response were observed for pre-treatment Ki-67 LI and SUVmax and for post-treatment Ki-67 LI, SUVmax and size. Change in Ki-67 LI was the best predictor of pathological complete response. Correlation patterns of the directly measured metabolic, morphological, and proliferation responses differed from those determined by scoring methods.
  
  
  CONCLUSIONS
  During PST, FDG-PET/CT enables for robust assessment of treatment efficacy, but more reliable scoring systems are still needed for more precise response evaluation.
authors.affiliation: Oncology Division, 1st Department of Internal Medicine, Semmelweis University, Budapest, Hungary.
authors.forename: Tímea
authors.initials: T
authors.lastname: Tőkés
authors.affiliation: Oncology Division, 1st Department of Internal Medicine, Semmelweis University, Budapest, Hungary.
authors.forename: Gyöngyvér
authors.initials: G
authors.lastname: Szentmártoni
authors.affiliation: Oncology Division, 1st Department of Internal Medicine, Semmelweis University, Budapest, Hungary.
authors.forename: László
authors.initials: L
authors.lastname: Torgyík
authors.affiliation: Oncology Division, 1st Department of Internal Medicine, Semmelweis University, Budapest, Hungary.
authors.forename: Krisztián
authors.initials: K
authors.lastname: Somlai
authors.affiliation: 2nd Department of Pathology, Semmelweis University, Budapest, Hungary.
authors.forename: Janina
authors.initials: J
authors.lastname: Kulka
authors.affiliation: Pozitron PET/CT Center, Budapest, Hungary.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Lengyel
authors.affiliation: Department of Nuclear Medicine, Semmelweis University, Budapest, Hungary Scanomed Ltd., Budapest, Hungary.
authors.forename: Tamás
authors.initials: T
authors.lastname: Györke
authors.affiliation: Oncology Division, 1st Department of Internal Medicine, Semmelweis University, Budapest, Hungary dank.oncology@gmail.com.
authors.forename: Magdolna
authors.initials: M
authors.lastname: Dank
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy*; D018567:Breast Neoplasms, Male / Q000000981:diagnostic imaging / Q000188:drug therapy; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D011877:Radionuclide Imaging; D016896:Treatment Outcome; D047368:Tumor Burden
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen
keywords: Breast cancer; FDG-PET/CT; Ki-67; primary systemic therapy; response evaluation