title: Metaplastic breast cancer: a comparison between the most common histologies with poor immunohistochemistry factors.
abstract: BACKGROUND
  Metaplastic carcinoma of the breast (MCB) is a rare histological type of breast cancer. This study aimed to determine whether MCB exhibits shorter overall survival (OS) and disease-free survival (DFS) compared with other histologies that are considered unfavorable.
  
  
  METHODS
  We retrospectively analyzed 157 clinical file records of the Mexico City-based National Institute of Cancerology and compared the clinical characteristics and treatment of 24 patients with MCB, 37 patients with triple-negative invasive lobular carcinoma (TN-ILC), 48 patients with high-grade invasive ductal carcinoma (HG-IDC), and 48 patients with triple-negative invasive ductal carcinoma (TN-IDC), paired by clinical stage and age. We performed a comparative analysis and analyzed OS and DFS using a log-rank test.
  
  
  RESULTS
  In patients with MCB, the 5-year DFS was 52.1% (mean, 48.52 months; 95%: 35.32-61.72), and the 5-year OS was 72.2% (mean, 59.77 months; 95% CI: 48.55-71.00). No differences were observed in the DFS of MCB compared with each of the other histologies (MCB vs. HG-IDC, p = 0.865; MCB vs. TN-IDC, p = 0.966, and MCB vs. TN-ILC, p = 0.132). Moreover, no differences were observed when comparing the OS of MCB with that of each of the other histologies (MCB vs. HG-IDC, p = 0.246; MCB vs. TN-IDC, p = 0.255, and MCB vs. TN-ILC, p = 0.387).
  
  
  CONCLUSIONS
  Neither OS nor DFS differ between patients with MCB and those with other histologies with unfavorable immunohistochemical factors.
authors.affiliation: Department of Breast Tumors, Instituto Nacional de Cancerología, Mexico City, Mexico. sbarquet@gmail.com.
authors.forename: Salim Abraham
authors.initials: SA
authors.lastname: Barquet-Muñoz
authors.affiliation: Department of Breast Tumors, Instituto Nacional de Cancerología, Mexico City, Mexico. patyvics@gmail.com.
authors.forename: Silvia Patricia
authors.initials: SP
authors.lastname: Villarreal-Colin
authors.affiliation: Direction of Research, Instituto Nacional de Cancerología, Mexico City, Mexico. herreram@biomedicas.unam.mx.
authors.forename: Luis Alonso
authors.initials: LA
authors.lastname: Herrera-Montalvo
authors.affiliation: Direction of Research, Instituto Nacional de Cancerología, Mexico City, Mexico. ernysoto@gmail.com.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Soto-Reyes
authors.affiliation: Direction of Research, Instituto Nacional de Cancerología, Mexico City, Mexico. carlos.pplas@gmail.com.
authors.forename: Carlos
authors.initials: C
authors.lastname: Pérez-Plasencia
authors.affiliation: Clinical Research, Instituto Nacional de Cancerología, Mexico City, Mexico. quiechc8@hotmail.com.
authors.forename: Jaime
authors.initials: J
authors.lastname: Coronel-Martínez
authors.affiliation: Department of Surgical Pathology, Instituto Nacional de Cancerología, Mexico City, Mexico. madeliapmg@hotmail.com.
authors.forename: Delia
authors.initials: D
authors.lastname: Pérez-Montiel
authors.affiliation: Department of Breast Tumors, Instituto Nacional de Cancerología, Mexico City, Mexico. vrrafa@yahoo.com.mx.
authors.forename: Rafael
authors.initials: R
authors.lastname: Vázquez-Romo
authors.affiliation: Clinical Research, Instituto Nacional de Cancerología, Mexico City, Mexico. dcantude@gmail.com.
authors.forename: David
authors.initials: D
authors.lastname: Cantú de León
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000378:metabolism / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D008679:Metaplasia; D008875:Middle Aged; D009026:Mortality; D060787:Neoplasm Grading; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D012189:Retrospective Studies; D016896:Treatment Outcome