title: Population-based comparison of prognostic factors in invasive micropapillary and invasive ductal carcinoma of the breast.
abstract: BACKGROUND
  Invasive micropapillary carcinoma (IMPC) is a variant of breast carcinoma with a higher propensity for lymph node metastases compared with invasive ductal carcinoma (IDC).
  
  
  METHODS
  Retrospective analysis of 636 IMPC and 297 735 IDC cases in the Surveillance, Epidemiology and End RESULTS database comparing disease-specific survival (DSS) and overall survival (OS) between IMPC and IDC.
  
  
  RESULTS
  A higher percentage of IMPC cases (52.0%) had nodal metastases compared with IDC cases (34.6%). The 5-year DSS and OS for IMPC was 91.8% and 82.9%, respectively compared with 88.6% and 80.5% for IDC, respectively. For both IMPC and IDC, oestrogen-receptor positivity was associated with better survival, while having four or more positive lymph nodes or larger tumour size correlated with worse survival. Radiotherapy provided a survival benefit for both histological types.
  
  
  CONCLUSIONS
  Despite IMPC's higher propensity for lymph node metastasis, IMPC has DSS and OS that compare favourably with IDC.
authors.affiliation: Department of Radiation Oncology, Baylor College of Medicine, Houston, TX, USA.
authors.forename: A C
authors.initials: AC
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, Houston Methodist Hospital, 6565 Fannin St. DB-077, Houston, TX 77030 USA.
authors.forename: A C
authors.initials: AC
authors.lastname: Paulino
authors.affiliation: Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, USA.
authors.forename: M R
authors.initials: MR
authors.lastname: Schwartz
authors.affiliation: Department of Medicine, Houston Methodist Hospital, Houston, TX, USA.
authors.forename: A A
authors.initials: AA
authors.lastname: Rodriguez
authors.affiliation: Department of Surgery, Houston Methodist Hospital, Houston, TX, USA.
authors.forename: B L
authors.initials: BL
authors.lastname: Bass
authors.affiliation: Department of Medicine, Houston Methodist Hospital, Houston, TX, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Chang
authors.affiliation: Department of Radiation Oncology, Houston Methodist Hospital, 6565 Fannin St. DB-077, Houston, TX 77030 USA.
authors.forename: B S
authors.initials: BS
authors.lastname: Teh
mesh_terms: D001943:Breast Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D018270:Carcinoma, Ductal, Breast / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D002291:Carcinoma, Papillary / Q000401:mortality / Q000473:pathology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D047368:Tumor Burden