title: Changes in chemotherapy usage and outcome of early breast cancer patients in the last decade.
abstract: During the last decade, neoadjuvant chemotherapy (NACT) of early breast cancer (EBC) evolved from a therapy intended to enable operability to a standard treatment option aiming for increasing cure rates equivalent to adjuvant chemotherapy (ACT). In parallel, improvements in the quality control of breast cancer care have been established in specialized breast care units.
  
  
  
  This study analyzed chemotherapy usage in patients with EBC treated at the Heidelberg University Breast Unit between January 2003 and December 2014.
  
  
  
  Overall, 5703 patients were included in the analysis of whom 2222 (39 %) received chemotherapy, 817 (37 %) as NACT, and 1405 (63 %) as ACT. The chemotherapy usage declined from 48 % in 2003 to 34 % in 2014 of the cohort. Further, the proportion of NACT raised from 42 to 65 % irrespective of tumor subtype. In addition, frequency of pathologic complete response (pCR) defined as no tumor residues in breast and axilla (ypT0 ypN0) at surgery following NACT increased from 12 % in 2003 to 35 % in 2014. The greatest effect was observed in HER2+ breast cancer with an increase in patients achieving pCR from 24 to 68 %.
  
  
  
  The results mirror the refined indication for chemotherapy in EBC and its preferred usage as NACT in Germany. The increase in pCR rate over time suggests improvement in outcome accomplished by a multidisciplinary decision-making process and stringent measures for quality control.
authors.affiliation: Department of Gynecology and Obstetrics, University of Heidelberg, Heidelberg, Germany.
authors.forename: A
authors.identifier: 0000-0002-7998-3796
authors.initials: A
authors.lastname: Hennigs
authors.affiliation: Department of Gynecology and Obstetrics, University of Heidelberg, Heidelberg, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Riedel
authors.affiliation: Department of Gynecology and Obstetrics, University of Heidelberg, Heidelberg, Germany.|National Center for Tumor Diseases (NCT), University of Heidelberg, Heidelberg, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Marmé
authors.affiliation: Department of Pathology, University of Heidelberg, Heidelberg, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Sinn
authors.affiliation: Department of Radiation Oncology, University of Heidelberg, Heidelberg, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Lindel
authors.affiliation: Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Gondos
authors.affiliation: Department of Gynecology and Obstetrics, University of Heidelberg, Heidelberg, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Smetanay
authors.affiliation: Department of Gynecology and Obstetrics, University of Heidelberg, Heidelberg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Golatta
authors.affiliation: Department of Gynecology and Obstetrics, University of Heidelberg, Heidelberg, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Sohn
authors.affiliation: Department of Gynecology and Obstetrics, University of Heidelberg, Heidelberg, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Schuetz
authors.affiliation: Department of Gynecology and Obstetrics, University of Heidelberg, Heidelberg, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Heil
authors.affiliation: Department of Gynecology and Obstetrics, University of Heidelberg, Heidelberg, Germany. andreas.schneeweiss@med.uni-heidelberg.de.|National Center for Tumor Diseases (NCT), University of Heidelberg, Heidelberg, Germany. andreas.schneeweiss@med.uni-heidelberg.de.
authors.forename: A
authors.initials: A
authors.lastname: Schneeweiss
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D060787:Neoplasm Grading; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor
keywords: Adjuvant chemotherapy; Certified breast cancer unit; Early breast cancer; Neoadjuvant chemotherapy; Pathologic complete response