Table 3.
Univariable logistic regression analysis with implant failure after revision surgery as the endpoint
| Univariable | ||||
|---|---|---|---|---|
| All cases | Implant failure | Odds ratio | p | |
| Total number of breasts | 542 | 33 | ||
| Age (years) at IBR | ||||
| < 50 | 319 | 21 | 1.00 (reference) | |
| 50–60 | 163 | 10 | 0.93 (0.43–2.02) | 0.850 |
| > 60 | 60 | 2 | 0.49 (0.11–2.14) | 0.343 |
| Missing | 0 | 0 | ||
| Histopathological tumour stage | ||||
| Tis (in situ only) | 135 | 11 | 1.00 (reference) | |
| T1 (≤ 20 mm) | 55 | 1 | 0.21 (0.03–1.66) | 0.138 |
| T2 (21–50 mm) | 112 | 4 | 0.42 (0.13–1.35) | 0.144 |
| T3/T4 (> 50 mm) | 86 | 5 | 0.70 (0.23–2.08 | 0.516 |
| Missing | 154 | 12 | ||
| Histopathological nodal stage | ||||
| Node negative | 407 | 17 | 1.00 (reference) | |
| Node positive | 111 | 14 | 3.31 (1.58–6.95) | 0.002 |
| Missing | 24 | 2 | ||
| Axillary clearance | ||||
| No | 290 | 7 | 1.00 (reference) | |
| Yes | 240 | 26 | 4.91 (2.09–11.53) | < 0.001 |
| Missing | 12 | 0 | ||
| Type of implant | ||||
| Temporary expander | 33 | 1 | 1.00 (reference) | |
| Permanent expander | 434 | 29 | 2.29 (0.30–17.37) | 0.422 |
| Fixed-volume implant | 68 | 2 | 0.97 (0.09–11.10) | 0.980 |
| Missing | 7 | 1 | ||
| Final implant volume* | ||||
| < 300 cc | 151 | 8 | 1.00 (reference) | |
| 300–400 cc | 265 | 12 | 0.85 (0.34–2.12) | 0.724 |
| > 400 cc | 118 | 10 | 1.66 (0.63–4.33) | 0.305 |
| Missing | 8 | 3 | ||
| Radiotherapy | ||||
| None | 288 | 9 | 1.00 (reference) | |
| Yes, prior to IBR | 24 | 2 | 2.82 (0.57–13.85) | 0.202 |
| Yes, after IBR | 223 | 22 | 3.39 (1.53–7.53) | 0.003 |
| Missing | 7 | 0 | ||
| Type of adjuvant radiotherapy** | ||||
| Local | 82 | 3 | 1.00 (reference) | |
| Locoregional | 141 | 19 | 4.10 (1.18–14.32) | 0.027 |
| Missing | 0 | 0 | ||
| Radiotherapy dose/fractions** | ||||
| 46 Gy/23 fractions | 18 | 2 | 1.00 (reference) | |
| 50 Gy/25 fractions | 198 | 20 | 0.90 (0.19–4.20) | 0.892 |
| Missing/other | 7 | 0 | ||
| Months from end of radiotherapy to first surgical revision | ||||
| > 9 months | 163 | 13 | 1.00 (reference) | |
| 6–9 months | 50 | 3 | 3.17 (0.78–12.80) | 0.106 |
| < 6 months | 14 | 3 | 0.74 (0.20–2.71) | 0.651 |
| Missing | 20 | 5 | ||
| Postoperative infection within 30 days after IBR | ||||
| No infection | 398 | 10 | 1.00 (reference) | |
| Clinical signs of infection, oral antibiotic treatment | 72 | 7 | 4.18 (1.54–11.37) | 0.005 |
| Confirmed infection, oral antibiotic treatmenta | 14 | 4 | 15.52 (4.15–58.01) | < 0.001 |
| Confirmed infection, intravenous antibiotic treatmenta | 12 | 3 | 12.93 (3.04–55.12) | 0.001 |
| Missing | 46 | 9 | ||
| Postoperative complication with return to theatre (within 30 days) after IBR | ||||
| No | 489 | 24 | 1.00 (reference) | |
| Yes | 11 | 1 | 1.94 (0.24–15.76) | 0.536 |
| Missing | 42 | 8 | ||
| Postoperative complication without return to theatre after IBR | ||||
| None | 464 | 23 | 1.00 (reference) | |
| Seroma | 44 | 4 | 1.92 (0.63–5.82) | 0.250 |
| Infection | 5 | 2 | 12.78 (2.04–80.30 | 0.007 |
| Bleeding | 8 | 1 | 2.74 (0.32–23.21) | 0.355 |
| Skin necrosis | 7 | 1 | 3.20 (0.37–27.66) | 0.291 |
| ≥ 2 complications | 14 | 2 | 3.20 (0.68–15.13) | 0.143 |
| Missing | 0 | 0 | ||
| Previous revision surgery performed | ||||
| No | 395 | 22 | 1.00 (reference) | |
| Yes | 147 | 11 | 1.37 (0.65–2.90) | 0.409 |
| Missing | 0 | 0 | ||
| BMIc | ||||
| Normal (18.5–30) | 438 | 18 | 1.00 (reference) | |
| Underweight (< 18.5) | 8 | 1 | 3.33 (0.39–28.55) | 0.272 |
| Overweight (> 30) | 23 | 3 | 3.50 (0.95–12–87) | 0.059 |
| Missing | 73 | 11 | ||
| Smokingc | ||||
| Never smoked | 383 | 19 | 1.00 (reference) | |
| Currently smoking | 65 | 11 | 3.90 (1.76–8.65) | 0.001 |
| Former smoker | 73 | 2 | 0.54 (0.12–2.37) | 0.414 |
| Missing | 21 | 1 | ||
| Immunosuppressive treatmentc | ||||
| No | 498 | 31 | 1.00 (reference) | |
| Yes | 9 | 2 | 3.57 (0.74–17.24) | 0.113 |
| Missing | 35 | 0 | ||
| Antihypertensive medicationc | ||||
| No | 454 | 26 | 1.00 (reference) | |
| Yes | 42 | 5 | 2.08 (0.76–5.70) | 0.155 |
| Missing | 46 | 2 | ||
| Diabetesc | ||||
| No | 502 | 31 | 1.00 (reference) | |
| Yes, with medicationb | 6 | 2 | 5.40 (1.05–27.85) | 0.044 |
| Missing | 34 | 0 | ||
Each case represents one operated breast
IBR immediate implant-based breast reconstruction
*Final expander volume or fixed-volume implant size
**Reporting only patients who had received RT after IBR
aConfirmed by positive bacterial cultures and/or elevated C-reactive protein
bIncluding oral medication and/or insulin
cRegistered at the time of IBR, not at implant revision surgery