title: Clinico-Pathologic Subtypes of Breast Cancer Primary Tumors Are Related to Prognosis after Recurrence
abstract: Background: Pathological factors, based mainly on immunohistochemistry (IHC) and histological differentiation,
  are mostly used to differentiate breast cancer (BC) subtypes. Our present aim was to describe the characteristics and
  survival of a relapsing BC patient cohort based on clinico-pathologic subtypes determined for the primary tumors.
  Methods: We used a clinico- pathological definition of BC subtypes based on histological grade (HG), estrogen
  receptor (ER), progesterone receptor (PgR),and epidermal growth factor receptor type 2 (HER2) expression assessed
  by IHC. We determined variables associated with loco-regional recurrence (LRR), second primaries (SP), systemic
  recurrence (SR) and post-recurrence survival (PRS). Results: Out of 1,702 patients, 240 (14%) had an event defined as
  recurrence. Those with recurrent disease were significantly younger than those without,and were initially diagnosed at
  more advanced stages, with larger tumors, greater lymph nodal involvement and higher HG. With a median follow up
  of 61 months (1-250), 4.6% of patients without recurrence and 56.6% of patients with an event defined as recurrence
  had died. The median PRS for the LRR group was 77 months; 75 months for those who developed a SP and 22 months
  for patients with an SR (p <0.0001). In SR cases, the median PRS was shorter for ER- tumors than for ER+ tumors
  (15 vs. 26 months, respectively; p = 0.0019, HR 0.44; CI: 0.25-0.44). Conclusions: Subtype, defined through classic
  histopathologic parameters determined for primary tumors, was found to eb related to type of recurrence and also to
  prognosis after relapse.
authors.affiliation: Pontificia Universidad Catolica de Chile. Email:csanchez@med.puc.cl
authors.forename: Cesar
authors.initials: C
authors.lastname: Sánchez
authors.forename: Mauricio
authors.initials: M
authors.lastname: Camus
authors.forename: Lidia
authors.initials: L
authors.lastname: Medina
authors.forename: David
authors.initials: D
authors.lastname: Oddo
authors.forename: Rocío
authors.initials: RC
authors.lastname: Artigas
authors.forename: Alejandra
authors.initials: A
authors.lastname: Pérez Sepúlveda
authors.forename: Francisco
authors.initials: F
authors.lastname: Domínguez
authors.forename: Dravna
authors.initials: D
authors.lastname: Razmilic
authors.forename: María Elena
authors.initials: MR
authors.lastname: Navarro
authors.forename: Hector
authors.initials: H
authors.lastname: Galindo
authors.forename: Francisco
authors.initials: F
authors.lastname: Acevedo
keywords: Breast cancer; subtypes; prognostic; recurrence