title: Cost-effectiveness analysis of strategies for HER2 testing of breast cancer patients in France.
abstract: OBJECTIVE
  A cost-effectiveness analysis was conducted comparing diagnostic strategies for determining the HER2 status of invasive breast carcinomas, as an indication for trastuzumab at metastatic relapse.
  
  
  METHODS
  A decision tree compared five strategies distinguished by (i) the use of immunohistochemical (IHC) and/or fluorescent in situ hybridization (FISH) techniques, and (ii) the test schedule (at initial diagnosis or metastatic relapse). Most cost and effectiveness data came from a French multicentric study of 2,045 patients from eight hospitals. We were not able to select final criteria for trastuzumab effectiveness, because published data rely on IHC techniques not used in France (i.e., HercepTest). We, therefore, selected two intermediate criteria for inappropriate treatment at relapse, that is, patients with HER2-amplified tumors not receiving trastuzumab (Criterion 1) and HER2-nonamplified tumors improperly treated with trastuzumab (Criterion 2). Sensitivity analyses were then performed to assess the robustness of the results to (i) discount rate, (ii) cost of FISH, and (iii) tissue fixation technique.
  
  
  RESULTS
  The strategy using IHC at diagnosis was dominated by the four other strategies. Among these approaches, the only efficient strategy for both criteria was IHC used alone at metastatic relapse; strategies using FISH, or IHC followed by FISH on IHC2+ cases were efficient for Criterion 1, whereas IHC followed by FISH on IHC2+ and 3+ cases was efficient for Criterion 2.
  
  
  CONCLUSIONS
  Determining HER2 status at diagnosis, as an indication for trastuzumab at metastatic relapse, incurs substantial incremental costs, which do not appear to be justified. No other strategy can be excluded at first.
authors.affiliation: Health Economics Research Group in Oncology, Centre Léon Bérard, Lyon, France. morelle@lyon.fnclcc.fr
authors.forename: Magali
authors.initials: M
authors.lastname: Morelle
authors.forename: Elodie
authors.initials: E
authors.lastname: Haslé
authors.forename: Isabelle
authors.initials: I
authors.lastname: Treilleux
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Michot
authors.forename: Thomas
authors.initials: T
authors.lastname: Bachelot
authors.forename: Frédérique
authors.initials: F
authors.lastname: Penault-Llorca
authors.forename: Marie-Odile
authors.initials: MO
authors.lastname: Carrère
mesh_terms: D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics*; D003362:Cost-Benefit Analysis; D003663:Decision Trees; D005260:Female; D005602:France; D005820:Genetic Testing / Q000191:economics* / Q000379:methods*; D006801:Humans; D007150:Immunohistochemistry / Q000191:economics; D017404:In Situ Hybridization, Fluorescence / Q000191:economics; D011446:Prospective Studies; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis*; D012008:Recurrence; D000068878:Trastuzumab
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab