Table 4.
Univariate and multivariate analysis of characteristics associated with risk of lymphedema (RVC ≥ 10 %)
| Univariate results | Multivariate resultsc | |||
|---|---|---|---|---|
| Hazard ratio (95 % CI) | p value | Hazard ratio (95 % CI) | p value | |
| Patient characteristics | ||||
| Age at surgery (years)a | 1.02 (1.00–1.03) | 0.1080 | 1.02 (1.00–1.04) | 0.0433 |
| Pre-operative BMIa (kg/m2) | 1.07 (1.04–1.10) | <0.0001 | 1.05 (1.02–1.09) | 0.0007 |
| Surgical characteristics | ||||
| Axillary surgery | ||||
| SLNB versus no axillary surgery | 0.83 (0.36–1.89) | 0.6507 | b | – |
| ALND versus no axillary surgery | 6.31 (2.88–13.80) | <0.0001 | 7.32 (3.16–17.01) | <0.0001 |
| ALND versus SLNB/no axillary surgery | 7.37 (4.86–11.19) | <0.0001 | 8.19 (5.12–13.10) | <0.0001 |
| Pathologic characteristics | ||||
| Invasive vs. DCIS | 2.20 (1.06–4.53) | 0.0335 | 1.05 (0.49–2.25) | 0.9041 |
| Number positive lymph nodesa | 1.10 (1.07–1.13) | <0.0001 | 1.02 (0.98–1.06) | 0.4337 |
| Systemic therapy | ||||
| Adjuvant taxane-based chemotherapy | ||||
| Yes versus no chemo | 2.61 (1.73–3.95) | <0.0001 | 1.14 (0.69–1.87) | 0.6188 |
| Yes versus non-taxane chemo | 2.90 (1.04–8.08) | 0.0412 | 1.56 (0.56–4.37) | 0.3988 |
| Paclitaxel | ||||
| Yes versus no chemo | 2.00 (1.23–3.24) | 0.0053 | 0.81 (0.46–1.41) | 0.4473 |
| Yes versus non-taxane chemo | 2.45 (0.85–7.07) | 0.0984 | 1.26 (0.43–3.65) | 0.6725 |
| Docetaxel | ||||
| Yes versus no chemo | 2.54 (1.52–4.26) | 0.0004 | 1.25 (0.71–2.18) | 0.4374 |
| Yes versus non-taxane chemo | 3.12 (1.06–9.20) | 0.0392 | 1.95 (0.65–5.85) | 0.2334 |
| Non-taxane chemotherapy | ||||
| Yes versus no chemo | 0.90 (0.32–2.52) | 0.8417 | 0.64 (0.22–1.83) | 0.4056 |
| Hormonal therapy | ||||
| Yes versus no | 1.59 (0.90–2.80) | 0.1098 | – | |
| Herceptin-based chemotherapy | ||||
| Yes versus no | 1.10 (0.55–2.20) | 0.7778 | – | – |
| Radiation therapy | ||||
| Yes versus no | 1.06 (0.65–1.75) | 0.8056 | – | – |
| RLNR versus breast+chest wall/none | 4.32 (2.82–6.63) | <0.0001 | 1.29 (0.77– 2.16) | 0.3354 |
CI confidence interval, BMI body mass index, SLNB sentinel lymph node biopsy, ALND axillary lymph node dissection, DCIS ductal carcinoma in situ, RLNR regional lymph node radiation
aAge at surgery, pre-operative BMI, and number of positive lymph nodes were analyzed as continuous variables such that the hazard ratios reflect the change in lymphedema risk associated with a 1-unit increase in the variable
b"–" indicates the specified variable/comparison was not analyzed
c2 Separate models, each including age at surgery, BMI and ALND were used to estimate the hazard ratios for (1) adjuvant taxane-based chemo and (2) individual effects of paclitaxel and docetaxel