title: Clinical utility of the IHC4+C score in oestrogen receptor-positive early breast cancer: a prospective decision impact study.
abstract: BACKGROUND
  Most oestrogen receptor (ER)-positive early breast cancer diagnosed today is highly curable with multimodality treatment. Systemic adjuvant treatments including endocrine therapy and chemotherapy have made a significant contribution to the increasing cure rates over the past three decades. However not all women will require chemotherapy. The IHC4+C score is a prognostic tool that integrates four immunohistochemical measures with clinicopathological features to estimate the residual risk of distant recurrence at 10 years in post-menopausal women with ER-positive breast cancer who have received 5 years of endocrine therapy. Retrospective studies indicate that the test can identify a set of women that are at such low risk of recurrence that chemotherapy can be of little benefit.
  
  
  METHODS
  In this study, 124 patients were prospectively selected from the multidisciplinary team meeting between January 2013 and April 2014 for IHC4+C testing. Adjuvant systemic treatment recommendations by clinicians were recorded without and with the availability of the score in addition to the patient's decision.
  
  
  RESULTS
  There was concordance in the MDT's recommendation without and with the availability of the score in 73% of cases. Clinicians recommended chemotherapy or at least its discussion to 74 (59%) patients, which fell to 32 (34%) patients after the IHC4+C score was made available, sparing one in four tested patients a chemotherapy recommendation, along with its toxicity and expense.
  
  
  CONCLUSIONS
  This decision impact study shows that when used by clinicians in the multidisciplinary team meeting for adjuvant decision-making, a significant proportion of patients are spared chemotherapy recommendations.
authors.affiliation: 1] Department of Medicine, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK [2] Academic Department of Biochemistry, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK [3] Institute of Cancer Research, Fulham Road, London SW3 6JB, UK.
authors.forename: B
authors.initials: B
authors.lastname: Yeo
authors.affiliation: 1] Academic Department of Biochemistry, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK [2] Institute of Cancer Research, Fulham Road, London SW3 6JB, UK.
authors.forename: L
authors.initials: L
authors.lastname: Zabaglo
authors.affiliation: Academic Department of Biochemistry, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK.
authors.forename: M
authors.initials: M
authors.lastname: Hills
authors.affiliation: Academic Department of Biochemistry, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK.
authors.forename: A
authors.initials: A
authors.lastname: Dodson
authors.affiliation: Department of Medicine, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK.
authors.forename: I
authors.initials: I
authors.lastname: Smith
authors.affiliation: 1] Academic Department of Biochemistry, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK [2] Institute of Cancer Research, Fulham Road, London SW3 6JB, UK.
authors.forename: M
authors.initials: M
authors.lastname: Dowsett
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D003657:Decision Making / Q000502:physiology*; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011960:Receptors, Estrogen / Q000378:metabolism; D012107:Research Design; D012189:Retrospective Studies
chemical_list: D011960:Receptors, Estrogen