title: IHC4 score plus clinical treatment score predicts locoregional recurrence in early breast cancer.
abstract: OBJECTIVE
  Immunohistochemical 4 (IHC4) score plus Clinical Treatment Score (CTS) is an inexpensive tool predicting risk of distant recurrence in women with early breast cancer (EBC). IHC4 score is based on ER, PR, HER2 and Ki67 index. This study explores the role of the combined score (IHC4 + CTS) in predicting risk of locoregional recurrence (LRR) in women with EBC who had breast conservation surgery (BCS) without adjuvant radiotherapy (study group). The secondary objective was to evaluate the clinicopathological differences between our study group and women who had adjuvant radiation following BCS (control group).
  
  
  METHODS
  Patients were selected from the local database over a 13-year period. IHC testing was done where results were missing. Combined scores were calculated using the appropriate formulae.
  
  
  RESULTS
  Patients in the study group (81 patients) had favorable clinicopathological features compared to the control group (1406 patients). The Cox regression indicated a statistically significant association between the combined score and the risk of LRR (p = 0.03). The incidence of LRR was zero, 20% and 33.3% in the low, intermediate and high risk groups respectively (p = 0.007). Margin status was the only variable not included in the combined score. The Cox regression analysis demonstrated that the combined score (p = 0.02) and the ordinal measure of margins (p = 0.03) were significant independent predictors of LRR.
  
  
  CONCLUSIONS
  This is the first study of its kind. The IHC4 score + CTS can be used to identify low risk women who can potentially avoid adjuvant radiotherapy.
authors: FRANZCR, Department of Radiation Oncology, The Canberra Hospital, Canberra, Australia. Electronic address: rupalakhanpal@gmail.com.
authors: Roopa
authors: R
authors: Lakhanpal
authors: Centre for Cancer Prevention, Wolfson Institute of Preventive Medicine, Queen Mary University, London, UK.
authors: Ivana
authors: I
authors: Sestak
authors: Centre for Advances in Epidemiology and IT, The Canberra Hospital, Canberra, Australia.
authors: Bruce
authors: B
authors: Shadbolt
authors: RCPA, Department of ACT Pathology, The Canberra Hospital, Canberra, Australia.
authors: Genevieve M
authors: GM
authors: Bennett
authors: RCPA, Department of ACT Pathology, The Canberra Hospital, Canberra, Australia.
authors: Michael
authors: M
authors: Brown
authors: RCPA, Department of ACT Pathology, The Canberra Hospital, Canberra, Australia.
authors: Tessa
authors: T
authors: Phillips
authors: ACT and SE NSW Breast Cancer Treatment Group, ACT Health, GPO Box 825, ACT 2601, Australia.
authors: Yanping
authors: Y
authors: Zhang
authors: Department of ACT Pathology, The Canberra Hospital, Canberra, Australia.
authors: Amanda
authors: A
authors: Bullman
authors: FRANZCR, Department of Radiation Oncology, The Canberra Hospital, Canberra, Australia.
authors: Angela
authors: A
authors: Rezo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia; D016022:Case-Control Studies; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D007150:Immunohistochemistry; D015994:Incidence; D019394:Ki-67 Antigen / Q000032:analysis; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000737:chemistry / Q000453:epidemiology; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018714:Radiotherapy, Adjuvant / Q000706:statistics & numerical data; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D012044:Regression Analysis; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D016896:Treatment Outcome; D000069584:Unilateral Breast Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000628:therapy
chemical_list: D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human
keywords: Adjuvant radiotherapy; Early breast cancer; Immunohistochemical 4 score; Locoregional recurrence