title: Does confirmatory tumor biopsy alter the management of breast cancer patients with distant metastases?
abstract: BACKGROUND
  Decisions about systemic treatment of women with metastatic breast cancer are often based on estrogen receptor (ER), progesterone receptor (PgR), and Her2 status of the primary tumor. This study prospectively investigated concordance in receptor status between primary tumor and distant metastases and assessed the impact of any discordance on patient management.
  
  
  METHODS
  Biopsies of suspected metastatic lesions were obtained from patients and analyzed for ER/PgR and Her2. Receptor status was compared for metastases and primary tumors. Questionnaires were completed by the oncologist before and after biopsy to determine whether the biopsy results changed the treatment plan.
  
  
  RESULTS
  Forty women were enrolled; 35 of them underwent biopsy, yielding 29 samples sufficient for analysis; 3/29 biopsies (10%) showed benign disease. Changes in hormone receptor status were observed in 40% (P = 0.003) and in Her2 status in 8% of women. Biopsy results led to a change of management in 20% of patients (P = 0.002).
  
  
  CONCLUSIONS
  This prospective study demonstrates the presence of substantial discordance in receptor status between primary tumor and metastases, which led to altered management in 20% of cases. Tissue confirmation should be considered in patients with clinical or radiological suspicion of metastatic recurrence.
authors.affiliation: Division of Hematology and Medical Oncology, Princess Margaret Hospital; Department of Medicine.
authors.forename: C
authors.initials: C
authors.lastname: Simmons
authors.affiliation: Division of Pathology, University Health Network.
authors.forename: N
authors.initials: N
authors.lastname: Miller
authors.affiliation: Division of Pathology, University Health Network.
authors.forename: W
authors.initials: W
authors.lastname: Geddie
authors.affiliation: Department of Interventional Radiology, University Health Network, University of Toronto, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Gianfelice
authors.affiliation: Division of Hematology and Medical Oncology, Princess Margaret Hospital; Department of Medicine.
authors.forename: M
authors.initials: M
authors.lastname: Oldfield
authors.affiliation: Division of Hematology and Medical Oncology, Princess Margaret Hospital.
authors.forename: G
authors.initials: G
authors.lastname: Dranitsaris
authors.affiliation: Division of Hematology and Medical Oncology, Princess Margaret Hospital; Department of Medicine. Electronic address: mark.clemons@uhn.on.ca.
authors.forename: M J
authors.initials: MJ
authors.lastname: Clemons
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000628:therapy; D005260:Female; D006801:Humans; D009362:Neoplasm Metastasis / Q000175:diagnosis*; D009367:Neoplasm Staging; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone