title: Estrogen receptor-negative, progesterone receptor-positive breast carcinoma: poor clinical outcome.
abstract: OBJECTIVE
  The biological significance of breast carcinomas negative (-) for estrogen receptor (ER), but positive (+) for progesterone receptor (PR) is unclear. It has been proposed that these tumors contain ER whose presence is masked in binding assays by endogenous estrogen. We analyzed the clinical outcome of 17 patients with ER-PR+ tumors.
  
  
  METHODS
  The disease-free and overall survival of a series of 300 women with invasive breast carcinoma was followed for 7 to 79 (median 41) months.
  
  
  RESULTS
  The recurrence rate was significantly greater in ER-PR+ tumors (8/17 [47%]) than in ER+PR+ tumors (27/177 [15%]), and it was similar to the high recurrence rate of ER-PR- tumors (21/57 [37%]). The cancer-related death rate was 3 1/2 times higher in the ER-PR+ group than in the ER+PR+ group. A significant association between ER-PR+ tumors and tumor recurrence or cancer-related death persisted even after correction for other variables associated with poor outcome (eg, tumor size and lymph node involvement).
  
  
  CONCLUSIONS
  Estrogen receptor-negative, progesterone receptor-positive breast carcinomas are biologically different from ER+PR+ tumors and have a poor clinical outcome.
authors.affiliation: Department of Pathology, The Bryn Mawr Hospital, PA 19010-3158, USA.
authors.forename: A A
authors.initials: AA
authors.lastname: Keshgegian
authors.forename: A
authors.initials: A
authors.lastname: Cnaan
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D009364:Neoplasm Recurrence, Local / Q000378:metabolism; D011379:Prognosis; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*
chemical_list: D011960:Receptors, Estrogen; D011980:Receptors, Progesterone