title: HER2 expression in breast cancer: correlation with endocrine function and psychological status in operable and metastatic breast cancer.
abstract: BACKGROUND
  Node involvement, negative estrogen receptor (ER) and HER2 expression are the main negative prognostic factors for breast cancer. Prolactin (PRL) is involved in the control of breast cancer growth and differentiation. Surgery-induced hyperprolactinemia seems to be a positive prognostic factor for operable breast cancer, whereas high PRL levels may predict a poor prognosis in women with metastatic breast cancer. In this study, we evaluated the relation between HER2 expression and PRL blood concentrations in women with metastatic breast cancer women and those whit operable breast cancer patients prior to before and 7 days after surgery.
  
  
  METHODS
  The study included 50 women with breast cancer, 22 of whom had metastatic disease. HER 2 expression and serum levels of PRL were evaluated by fluorescence in situ hybridization (FISH) method and immunoradiometric assay (IRMA) method, respectively.
  
  
  RESULTS
  HER2 expression occurred in 11/28 operable cases and in 8/22 metastatic cases. The percentage of surgery-induced hyperprolactinemia was significantly higher in HER2-negative patients than in those with its expression. Moreover, HER2-positive metastatic cases showed significantly higher mean serum PRL levels than in the negative group.
  
  
  CONCLUSIONS
  These preliminary results show that metastatic cancer-related hyperprolactinemia and lack of surgery-induced hyperprolactinemia are statistically more frequent in HER2-positive patients, thus suggesting a link between PRL endogenous secretion and HER2 expression in breast cancer.
authors.affiliation: Institue of Biological Medicine, Milan, Italy. p.lissoni@hsgerardo.org
authors.forename: Paolo
authors.initials: P
authors.lastname: Lissoni
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Messina
authors.forename: Franco
authors.initials: F
authors.lastname: Rovelli
authors.forename: Fernando
authors.initials: F
authors.lastname: Brivio
authors.forename: Luca
authors.initials: L
authors.lastname: Fumagalli
authors.forename: Silvia
authors.initials: S
authors.lastname: Villa
authors.forename: Erio
authors.initials: E
authors.lastname: Bartolacelli
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000235:genetics* / Q000556:secondary; D001943:Breast Neoplasms / Q000097:blood / Q000235:genetics* / Q000473:pathology; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D006801:Humans; D006966:Hyperprolactinemia / Q000097:blood / Q000235:genetics* / Q000473:pathology; D015592:Immunoradiometric Assay; D017404:In Situ Hybridization, Fluorescence; D008408:Mastectomy / Q000523:psychology*; D011183:Postoperative Complications / Q000097:blood; D011184:Postoperative Period; D011388:Prolactin / Q000097:blood*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D011960:Receptors, Estrogen
chemical_list: D004273:DNA, Neoplasm; D011388:Prolactin; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; C508053:ERBB2 protein, human