title: Prognostic implications of receptor discordance between primary and recurrent breast cancer.
abstract: BACKGROUND
  Discordance rates of hormone receptor (HR) and human epidermal growth factor-2 (HER2) status between primary and recurrent breast cancer were reported to be in the wide range of 10-40 %, although its prognostic relevance remains to be elucidated.
  
  
  METHODS
  Fifty-five breast cancer patients had biopsies or resections of recurrent lesions. Pathological assessments of the HR and HER2 status of primary and recurrent lesions were performed in a single laboratory at Keio University Hospital. Tumors were classified as luminal (HR+ and HER2-), luminal/HER2 (HR+ and HER2+), HER2 (HR- and HER2+), or triple negative (HR- and HER2-).
  
  
  RESULTS
  Discordance rates in estrogen receptor (ER), progesterone receptor (PgR) and HER2 status between primary tumors and recurrent lesions were 16.4, 30.9 and 10.2 %, respectively. Overall, 14 patients (25.5 %) changed subtypes at recurrent lesions. Patients with a gain in ER and PgR status had a significantly longer disease-free interval compared with the corresponding concordant-negative patients (ER: 99.0 vs. 18.5 months, p = 0.037, PgR: 141.0 vs. 24.4 months, p = 0.011). Patients with a loss of HER2 status experienced a trend toward shorter time to progression, compared with patients who maintained HER2 positivity (4.0 vs. 18.4 months, p = 0.051).
  
  
  CONCLUSIONS
  Discordance in receptor status between primary and recurrent breast cancers were seen in 10-30 %. A gain in HR status was significantly associated with better prognosis.
authors.affiliation: Department of Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo, 160-8582, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Matsumoto
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Jinno
authors.forename: Takeshi
authors.initials: T
authors.lastname: Murata
authors.forename: Tomoko
authors.initials: T
authors.lastname: Seki
authors.forename: Maiko
authors.initials: M
authors.lastname: Takahashi
authors.forename: Tetsu
authors.initials: T
authors.lastname: Hayashida
authors.forename: Kaori
authors.initials: K
authors.lastname: Kameyama
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kitagawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000378:metabolism* / Q000628:therapy; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000378:metabolism*; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis*; D011960:Receptors, Estrogen / Q000096:biosynthesis*; D011980:Receptors, Progesterone / Q000096:biosynthesis*; D012189:Retrospective Studies; D016019:Survival Analysis
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human