Table 3.

Early-distant recurrence: univariate and multivariate Cox model analysis after stepwise variable selection by AIC of likelihood of early-distant recurrence in Stockholm TAM and multi-institutional cohorts for all (ER+) and ER+/HER2 only patients

All patients (ER+)ER+/HER2 only
VariableaHR (95% CI)PHR (95% CI)P
Stockholm TAMn = 317 (13 DR)n = 295 (11 DR)
 Univariate analysis
  Age at surgery0.76 (0.26–2.20)0.620.59 (0.19–1.86)0.37
  Tumor size1.68 (0.46–6.21)0.442.44 (0.63–9.45)0.20
  Tumor grade1.28 (0.28–5.84)0.751.08 (0.23–5.08)0.92
  PR status1.03 (0.28–3.79)0.970.69 (0.18–2.66)0.59
  HER2 status2.56 (0.56–11.68)0.23NANA
  BCI9.08 (1.86–44.4)0.00616.25 (2.59–102.0)0.003
 Multivariate analysis
  BCI9.08 (1.86–44.4)0.00616.25 (2.59–102.0)0.003
Multi-institutionaln = 358 (34 DR)n = 316 (26 DR)
 Univariate analysis
  Age at surgery1.10 (0.80–1.50)0.571.16 (0.81–1.65)0.42
  Tumor size1.77 (0.90–3.47)0.101.49 (0.68–3.24)0.32
  Tumor grade3.21 (0.98–10.51)0.052.55 (0.77–8.49)0.13
  HER2 status2.44 (1.10–5.39)0.03NANA
  Chemo0.99 (0.48–2.04)0.981.08 (0.49–2.48)0.86
  BCI11.92 (4.53–31.33)<0.000113.71 (4.54–41.36)<0.0001
 Multivariate analysis
  Tumor grade2.32 (0.71–7.58)0.17NANA
  BCI11.50 (4.22–31.32)<0.000113.71 (4.54–41.36)<0.0001

Abbreviations: AIC, Akaike's Information Criterion; DR, distant recurrences; NA, not applicable.

  • aAge was by 10 years increment; tumor size was greater than 2 cm versus 2 cm or less; tumor grade was moderate/poorly differentiated versus well differentiated; PR and HER2 status was positive versus negative; chemo was no versus yes; BCI was continuous variable with 5 units increment (chosen to dichotomize BCI to facilitate the comparison of HRs with clinical covariates).