title: Alterations in hormonal receptor expression and HER2 status between primary breast tumors and paired nodal metastases: discordance rates and prognosis.
abstract: BACKGROUND
  We aimed to evaluate the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression discordance in matched pairs of primary breast cancer and lymph node metastasis specimens and determine the effect of discordance on prognosis.
  
  
  METHODS
  Among all patients diagnosed with lymph node metastases from 2004 to 2007, primary tumors and paired lymph node metastases were resected from 209 patients. The status of ER, PR, and HER2 expression was analyzed immunohistochemically in 200, 194, and 193 patients, respectively. Discordance was correlated with prognosis.
  
  
  RESULTS
  Biomarker discordance between primary tumors and paired lymph node metastases was 25.0% (50/200) for ER status, 28.9% (56/194) for PR status, and 14.0% (27/193) for HER2 status. ER positivity was a significant independent predictor of improved survival when analyzed in primary tumors and lymph node metastases. Patients with PR-positive primary tumors and paired lymph node metastases displayed significantly enhanced survival compared to patients with PR-positive primary tumors and PR-negative lymph node metastases. Patients with ER- and PR-positive primary tumors and paired lymph node metastases who received endocrine therapy after surgery displayed significantly better survival than those not receiving endocrine therapy. Similalry treated patients with PR-negative primary tumors and PR-positive paired lymph node metastases also displayed better survival than those not receiving endocrine therapy.
  
  
  CONCLUSIONS
  Biomarker discordance was observed in matched pairs of primary tumors and lymph node metastases. Such cases displayed poor survival. Thus, it is important to reassess receptor biomarkers used for lymph node metastases.
authors.affiliation: Department of Breast Surgery, General Surgery, the First Hospital of China Medical University, Liaoning Province, China E-mail : jinfeng66cn@hotmail.com, bajinlingno12@126.com.
authors.forename: Jin-Ling
authors.initials: JL
authors.lastname: Ba
authors.forename: Cai-Gang
authors.initials: CG
authors.lastname: Liu
authors.forename: Feng
authors.initials: F
authors.lastname: Jin
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D002277:Carcinoma / Q000737:chemistry* / Q000556:secondary / Q000628:therapy; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000737:chemistry*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*; D011960:Receptors, Estrogen / Q000032:analysis*; D011980:Receptors, Progesterone / Q000032:analysis*; D000198:Spectinomycin / Q000031:analogs & derivatives; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D000198:Spectinomycin; C043267:trospectomycin; C508053:ERBB2 protein, human