Annelotte van Bommel

67 Variation in immediate breast reconstruction higher likelihood of IBR than the reference category of HR+/HER2-negative tumors (OR 1.31; 95% CI 1.14–1.50). Compared to the reference category, patients with triple-negative tumors had a similar chance of receiving IBR. All predictive factors (age, TNMclassification, multifocality, histology, tumor grade, and receptor groups) remained statistically significant in multivariate analyses ( Table 3 ). Table 3. Univariate and multivariate analyses of factors determining the use of immediate breast reconstruction after mastectomy in 15,072 invasive breast cancer patients operated between 2011 and 2013 in the Netherlands. Univariate Analysis Multivariate Analyses n OR 95% CI OR 95% CI Age Below 50 1170 1.73 1.58 - 1.91 2.09 1.89 - 2.32 50 to 65 1153 ref ref 65 or above 211 0.13 0.11 - 0.15 0.13 0.11 - 0.15 Clinical tumor stadium cTx / Unknown 288 1.41 1.22 - 1.64 1.24 1.05 - 1.47 cT1 1248 ref ref cT2 864 0.61 0.55 - 0.67 0.68 0.61 - 0.76 cT3 125 0.34 0.28 - 0.41 0.34 0.28 - 0.43 cT4 11 0.07 0.04 - 0.12 0.10 0.06 - 0.19 Clinical lymph node stadium cNx / Unknown 108 0.91 0.74 - 1.13 0.72 0.57 - 0.92 cN0 2098 ref ref cN1 307 0.40 0.35 - 0.46 0.37 0.32 - 0.43 cN2 9 0.33 0.17 - 0.65 0.36 0.18 - 0.72 cN3 14 0.32 0.18 - 0.55 0.33 0.18 - 0.58 Multifocal No 1681 ref ref Yes 855 1.38 1.26 - 1.51 1.14 1.03 - 1.26 Histology Ductal 2025 ref Lobular 265 0.61 0.53 - 0.70 0.71 0.61 - 0.83 Combination 103 1.20 0.96 - 1.50 1.19 0.93 - 1.52 Other 143 1.00 0.83 - 1.21 1.12 0.91 - 1.39 Grade 1 513 ref ref 2 1065 0.74 0.66 - 0.83 0.84 0.73 - 0.96 3 685 0.69 0.61 - 0.78 0.64 0.55 - 0.75 Unknown 273 0.76 0.64 - 0.89 0.98 0.81 - 1.19 Receptor groups HR positive, Her2 negative 1608 ref ref HR positive, Her2 positive 294 1.31 1.14 - 1.50 1.22 1.04 - 1.42 HR negative, Her2 positive 135 1.00 0.83 - 1.21 1.06 0.85 - 1.31 Triple negative 292 1.02 0.89 - 1.17 1.15 0.98 - 1.36 Unknown 207 0.94 0.80 - 1.10 0.92 0.77 - 1.09 CI, Confidence interval; OR, Odds Ratio; HR, Hormone Receptor. 4