Table 2. Univariable and Multivariable Association of Baseline Variables With Lymphedema Using 3 Definitions for Lymphedema.
| Variable | Objective Measurement | Patient Report | |||||||
|---|---|---|---|---|---|---|---|---|---|
| No. | 10% Volume Increase | 20% Volume Increase | No. | Lymphedema Symptoms (Heaviness or Swelling) | |||||
| HR (95% CI) | P Value | HR (95% CI) | P Value | HR (95% CI) | P Value | ||||
| Univariable Analysis | |||||||||
| Age, y | |||||||||
| <50 | 201 | 1 [Reference] | .32 | 1 [Reference] | .79 | 225 | 1 [Reference] | .99 | |
| 50-59 | 117 | 1.31 (0.96-1.76) | 1.12 (0.76-1.66) | 122 | 1.02 (0.70-1.49) | ||||
| 60-69 | 59 | 1.10 (0.74-1.64) | 1.27 (0.79-2.07) | 67 | 0.94 (0.59-1.52) | ||||
| ≥70 | 11 | 0.79 (0.32-1.94) | 1.12 (0.41-3.08) | 15 | 0.93 (0.34-2.55) | ||||
| Age, continuous, y | 388 | 1.00 (0.99-1.02) | .78 | 1.01 (0.99-1.03) | .27 | 429 | 1.00 (0.98-1.02) | .99 | |
| BMI category | |||||||||
| <30 | 216 | 1 [Reference] | .15 | 1 [Reference] | .17 | 235 | 1 [Reference] | .008 | |
| ≥30 | 170 | 1.22 (0.93-1.60) | 1.27 (0.90-1.79) | 192 | 1.56 (1.12-2.17) | ||||
| BMI, continuous | 386 | 1.01 (0.99-1.03) | .45 | 1.01 (0.99-1.04) | .34 | 427 | 1.04 (1.01-1.06) | .004 | |
| Tumor biology | |||||||||
| ERBB2 positive/ERBB2 negative | 185 | 1 [Reference] | .26 | 1 [Reference] | .38 | 202 | 1 [Reference] | .30 | |
| ERBB2 positive | 108 | 0.85 (0.61-1.19) | 0.96 (0.63-1.46) | 124 | 1.29 (0.88-1.90) | ||||
| Triple negative | 95 | 1.18 (0.85-1.63) | 1.29 (0.86-1.95) | 103 | 1.30 (0.86-1.96) | ||||
| Length of NAC, d | .009 | ||||||||
| <105 | 116 | 0.99 (0.71-1.37) | .86 | 1.10 (0.70-1.72) | 127 | 0.90 (0.59-1.38) | .03 | ||
| 105-143 | 151 | 1 [Reference] | 1 [Reference] | 165 | 1 [Reference] | ||||
| ≥144 | 121 | 1.08 (0.78-1.49) | 1.79 (1.19-2.68) | 137 | 1.48 (1.01-2.17) | ||||
| Length of NAC, continuous, d | 1.00 (1.00-1.01) | .28 | 1.01 (1.00-1.01) | .004 | 1.00 (1.00-1.01) | .11 | |||
| Chemotherapy regimen | |||||||||
| Anthracycline | 12 | 1 [Reference] | .32 | 1 [Reference] | .30 | 21 | 1 [Reference] | .45 | |
| Taxane | 71 | 1.20 (0.47-3.06) | 0.74 (0.25-2.20) | 76 | 1.28 (0.44-3.70) | ||||
| Both | 301 | 1.52 (0.62-3.69) | 1.11 (0.41-3.01) | 327 | 1.58 (0.58-4.29) | ||||
| Radiotherapy | |||||||||
| Received radiotherapy, including nodal radiotherapy | 252 | 1 [Reference] | .68 | 1 [Reference] | .15 | 276 | 1 [Reference] | .42 | |
| Received radiotherapy without nodal radiotherapy | 93 | 1.12 (0.82-1.53) | 1.40 (0.95-2.07) | 103 | 0.76 (0.50-1.15) | ||||
| Did not receive radiotherapy | 43 | 0.92 (0.58-1.45) | 1.43 (0.84-2.45) | 50 | 0.92 (0.53-1.58) | ||||
| Surgery type | |||||||||
| Mastectomy | 234 | 1 [Reference] | .19 | 1 [Reference] | .64 | 261 | 1 [Reference] | .90 | |
| Partial mastectomy | 152 | 1.20 (0.91-1.58) | 1.09 (0.77-1.54) | 166 | 0.98 (0.70-1.37) | ||||
| Total nodes removed | |||||||||
| <30 | 350 | 1 [Reference] | .008 | 1 [Reference] | .08 | 392 | 1 [Reference] | .30 | |
| ≥30 | 38 | 1.70 (1.15-2.52) | 1.56 (0.95-2.56) | 37 | 1.31 (0.78-2.21) | ||||
| Total nodes removed, continuous | 388 | 1.02 (1.00-1.03) | .048 | 1.01 (0.99-1.03) | .30 | 429 | 1.00 (0.98-1.03) | .62 | |
| Total positive nodes | |||||||||
| 0 | 164 | 1 [Reference] | .22 | 1 [Reference] | .33 | 183 | 1 [Reference] | .46 | |
| 1-3 | 126 | 1.03 (0.74-1.41) | 0.97 (0.64-1.46) | 135 | 1.28 (0.87-1.89) | ||||
| 4-9 | 74 | 1.73 (1.02-2.91) | 1.64 (0.84-3.23) | 85 | 1.23 (0.63-2.42) | ||||
| ≥10 | 24 | 1.11 (0.76-1.62) | 1.29 (0.82-2.04) | 26 | 1.35 (0.87-2.09) | ||||
| Total positive nodes, continuous | 388 | 1.03 (1.00-1.06) | .03 | 1.03 (0.99-1.07) | .15 | 429 | 1.02 (0.98-1.06) | .32 | |
| Multivariable Analysis | |||||||||
| Age, continuous, y | NA | 1.00 (0.99-1.01) | .95 | 1.01 (0.99-1.03) | .30 | NA | 1.00 (0.98-1.01) | .75 | |
| BMI, continuous | NA | 1.00 (0.98-1.02) | .95 | 1.01 (0.98-1.03) | .55 | NA | 1.03 (1.01-1.06) | .011 | |
| Length of NAC, d | |||||||||
| <105 | NA | 0.93 (0.66-1.30) | .85 | 1.05 (0.67-1.66) | .01 | NA | 0.88 (0.57-1.36) | .06 | |
| 105-143 | NA | 1 [Reference] | 1 [Reference] | NA | 1 [Reference] | ||||
| ≥144 | NA | 1.02 (0.73-1.42) | 1.74 (1.15-2.62) | NA | 1.42 (0.96-2.09) | ||||
| Radiotherapy | |||||||||
| Received radiotherapy | NA | 1 [Reference] | .82 | 1 [Reference] | .35 | NA | 1 [Reference] | .91 | |
| Did not receive radiotherapy | NA | 0.95 (0.60-1.50) | 1.29 (0.76-2.19) | NA | 0.97 (0.56-1.67) | ||||
| Total nodes removed, continuous | NA | 1.02 (1.00-1.03) | .08 | 1.00 (0.98-1.03) | .68 | NA | 1.00 (0.98-1.02) | .82 | |
| Total positive nodes, continuous | NA | 1.03 (1.00-1.06) | .06 | 1.02 (0.98-1.06) | .40 | NA | 1.01 (0.97-1.05) | .61 | |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); HR, hazard ratio; NA, not applicable; NAC, neoadjuvant chemotherapy.