Figure 1
Maximum late side effects in patients with and without gold fiducial marker implantation
| Gastrointestinal toxicity | Genitourinary toxicity | |||
|---|---|---|---|---|
| Grade | Gold fiducial markers | No gold fiducial markers | Gold fiducial markers | No gold fiducial markers |
| 0 | 59% | 50% | 37% | 35% |
| 1 | 12% | 15% | 27% | 25% |
| 2 | 24% | 35% | 34% | 35% |
| 3 | 5% | 0% | 2% | 5% |
Dose-volume histograms for patients with and without gold fiducial markers (GFM)
| GFM | No GFM | |
|---|---|---|
| PTV prostate cm3median (IQR) | 124.72 (98.68–152.83) | 157.12 (128.34–173.66) |
| PTV Dmax/D1 median (IQR) | 81.55 (80.55 – 82.75) | 81.15 (80.46–82.06) |
| PTV Dmean median (IQR) | 78.10 (77.41–78.70) | 78.10 (77.00–78.43) |
| CTV prostate cm3median (IQR) | 44.14 (34.75– 64.70) | 43.91 (34.40– 55.42) |
| CTV Dmax/D1 median (IQR) | 81.24 (80.64– 82.57) | 81.22 (80.35– 81.85) |
| CTV Dmean median (IQR) | 78.58 (77.97–79.47) | 78.63 (77.94–79.04) |
| CTV Dmin median (IQR) | 76.00 (75.36–76.32) | 76.49 (75.88–77.05) |
| Rectal volume median (IQR) | 113.02 (100.22–134.55) | 114.53 (105.57–136.38) |
| Rectal Dmax median (IQR) | 80.06 (78.88– 81.98) | 80.24 (79.23–81.25) |
| Rectal Dmean median (IQR) | 35.99 (32.94–39.61) | 39.30 (37.81–42.99) |
| Rectal V70 Gy % median (IQR) | 11.41 (9.41–13.04) | 16.12 (14.55–18.66) |
| Rectal V70 Gy cm3median (IQR) | 13.21 (11.33–15.93) | 18.66 (16.55–21.39) |
| Rectal V60 Gy % median (IQR) | 19.95 (16.39–22.37) | 25.25 (23.77–29.26) |
| Rectal V60 Gy cm3median (IQR) | 23.36 (19.93–25.98) | 29.23 (26.74–33.13) |
| Bladder volume median (IQR) | 196.93 (113.66–282.94) | 155.76 (127.30–296.44) |
| Bladder Dmax/D1 median (IQR) | 78.78 (77.01–80.53) | 79.53 80.44(77.04) – |
| Bladder Dmean median (IQR) | 21.11 (16.92–30.06) | 28.10 (18.99–35.20) |
| Bladder V70 Gy % median (IQR) | 7.50 (5.44–11.78) | 9.43 (6.06–14.02) |
| Bladder (IQR) V70 Gy cm3median | 14.14 (10.53–21.16) | 19.01 (12.00–22.20) |
| Bladder V50 Gy % median (IQR) | 17.14 (12.00–26,40) | 20.81 30.86(13.60) – |
| Bladder (IQR) V50 Gy cm3median | 34.00 (23.17–42.23) | 37.58 (27.16–44.42) |
| Bladder V30 Gy % median (IQR) | 28.24 (21.74–41.73) | 41.31 (25.78–51.83) |
| Bladder V30 Gy cm3median (IQR) | 58.71 (43.43– 78.57) | 65.38 (48.97–83.61) |
Uni- and multivariable Cox regression of the onset of late gastrointestinal or genitourinary toxicity grade 2 or higher
| GI | Univariable analysis | Multivariable analysis | ||||
|---|---|---|---|---|---|---|
| Variable | p-value | exp(HR) | exp(HR) (95% conf.) | p-value | exp(HR) | exp(HR) (95% conf.) |
| Use of GFM | 0.89 | 0.936 | 0.368–2.378 | - | - | - |
| Acute GI grade 2 | 0.09 | 2.642 | 0.875–7.981 | - | - | - |
| Age at RT | 0.03 | 1.124 | 1.010–1.252 | 0.101 | 1.092 | 0.983-1.213 |
| PTV prostate | 0.06 | 0.987 | 0.974–1.000 | - | - | - |
| PTV Dmax/D1 | 0.76 | 1.037 | 0.824–1.305 | - | - | - |
| PTV Dmean | 0.49 | 1.158 | 0.767–1.747 | - | - | - |
| CTV prostate | 0.03 | 0.966 | 0.936–0.996 | 0.073 | 0.972 | 0.942–1.003 |
| CTV Dmax/D1 | 0.55 | 1.056 | 0.884–1.263 | - | - | - |
| CTV Dmean | 0.51 | 1.090 | 0.843–1.410 | - | - | - |
| CTV Dmin | 0.64 | 1.042 | 0.877–1.236 | - | - | - |
| Rectal Volume | 0.29 | 1.007 | 0.994–1.020 | - | - | - |
| Rectal Dmax | 0.29 | 1.125 | 0.906–1.397 | - | - | - |
| Rectal Dmean | 0.25 | 0.951 | 0.973–1.036 | - | - | - |
| Rectal V70 Gy % | 0.59 | 0.971 | 0.875–1.078 | - | - | - |
| Rectal V70 Gy cm3 | 0.42 | 1.040 | 0.945–1.144 | - | - | - |
| Rectal V60 Gy % | 0.42 | 0.969 | 0.899–1.046 | - | - | - |
| Rectal V60 Gy cm3 | 0.50 | 1.024 | 0.955–1.099 | - | - | - |
| GU | Univariable analysis | |||||
| Variable | p-value | exp(HR) | exp(HR) (95% conf.) | |||
| Use of GFM | 0.93 | 1.041 | 0.441–2.459 | - | - | - |
| Acute GU grade 2 | 0.09 | 2.042 | 0.892–4.673 | - | - | - |
| Age at RT | 0.50 | 1.026 | 0.952–1.106 | - | - | - |
| PTV prostate | 0.29 | 1.006 | 0.995–1.017 | - | - | - |
| PTV Dmax/D1 | 0.14 | 0.808 | 0.611–1.068 | - | - | - |
| PTV Dmean | 0.04 | 0.573 | 0.342–0.961 | - | - | - |
| CTV prostate | 0.93 | 0.999 | 0.989–1.010 | - | - | - |
| CTV Dmax/D1 | 0.93 | 1.006 | 0.895–1.130 | - | - | - |
| CTV Dmean | 0.67 | 1.025 | 0.916–1.147 | - | - | - |
| CTV Dmin CTV | 0.58 | 1.035 | 0.918–1.165 | - | - | - |
| Bladder volume | 0.72 | 0.999 | 0.997–1.002 | - | - | - |
| Bladder Dmax/D1 | 0.24 | 0.973 | 0.696–1.094 | - | - | - |
| Bladder Dmean | 0.89 | 0.997 | 0.960–1.036 | - | - | – |
| Bladder V70 Gy % | 0.49 | 0.977 | 0.913–1.045 | - | - | - |
| Bladder V70 Gy cm3 | 0.23 | 0.969 | 0.921–1.020 | - | - | - |
| Bladder V50 Gy % | 0.54 | 0.988 | 0.951–1.027 | - | - | - |
| Bladder V50 Gy cm3 | 0.29 | 0.985 | 0.957–1.013 | - | - | - |
| Bladder V30 Gy % | 0.79 | 0.997 | 0.974–1.020 | - | - | - |
| Bladder V30 Gy cm3 | 0.70 | 0.997 | 0.980–1.014 | - | - | - |
Maximum acute side effects in patients with and without gold fiducial marker implantation
| Gastrointestinal toxicity | Genitourinary toxicity | |||
|---|---|---|---|---|
| Grade | Gold fiducial markers | No gold fiducial markers | Gold fiducial markers | No gold fiducial markers |
| 0 | 27% | 15% | 17% | 5% |
| 1 | 66% | 65% | 44% | 55% |
| 2 | 7% | 20% | 39% | 40% |
Uni- and multivariable Cox regression of biochemical no evidence of disease (bNED) and overall survival (OS)
| Univariable analysis | Multivariable analysis | |||||
|---|---|---|---|---|---|---|
| bNED | p-value | exp(HR) | exp(HR) (95% conf.) | p-value | exp(HR) | exp(HR) (95% conf.) |
| Use of GFM | 0.603 | 1.788 | 0.200–16.018 | - | - | - |
| Age at RT | 0.960 | 0.996 | 0.857–1.157 | - | - | - |
| PTV prostate | 0.789 | 1.003 | 0.980–1.027 | - | - | - |
| PTV Dmax/D1 | 0.556 | 1.133 | 0.747–1.719 | - | - | - |
| PTV Dmean | 0.960 | 0.978 | 0.410–2.332 | - | - | - |
| CTV prostate | 0.006 | 1.020 | 1.006–1.035 | 0.862 | 0.996 | 0.947–1.046 |
| CTV Dmax/D1 | 0.014 | 0.814 | 0.690–0.960 | 0.224 | 2.583 | 0.560–11.925 |
| CTV Dmean | 0.005 | 0.858 | 0.770–0.956 | 0.298 | 0.188 | 0.008–4.393 |
| CTV Dmin | 0.005 | 0.875 | 0.797–0.960 | 0.453 | 2.067 | 0.310–13.770 |
| OS | Univariable analysis | |||||
| p-value | exp(HR) | exp(HR) (95% conf.) | ||||
| Use of GFM | 0.564 | 1.907 | 0.213–17.063 | - | - | - |
| Age at RT | 0.235 | 1.149 | 0.913–1.446 | - | - | - |
| PTV Prostate | 0.723 | 1.004 | 0.984–1.024 | - | - | - |
| PTV Dmax/D1 | 0.300 | 0.705 | 0.364–1.366 | - | - | - |
| PTV Dmean | 0.153 | 0.426 | 0.132–1.373 | - | - | - |
| CTV Prostate | 0.833 | 1.002 | 0.980–1.025 | - | - | - |
| CTV Dmax/D1 | 0.775 | 0.964 | 0.747–1.242 | - | - | - |
| CTV Dmean | 0.946 | 0.992 | 0.791–1.245 | - | - | - |
| CTV Dmin | 0.879 | 1.024 | 0.758–1.383 | - | - | - |
Patient characteristics
| GFM | % | No GFM | % | |
|---|---|---|---|---|
| n | 41 | 100% | 20 | 100% |
| cT category | ||||
| 1 | 23 | 56% | 16 | 80% |
| 2 | 18 | 44% | 4 | 20% |
| iPSA in μg/l, median (IQR) | 7 (5.3/8.7) | 5.9 (4.4/10.6) | ||
| Gleason score | ||||
| 6 | 26 | 63% | 18 | 90% |
| 7a | 12 | 29% | 1 | 5% |
| 7b | 3 | 7% | 1 | 5% |
| Risk group | ||||
| Low risk | 16 | 39% | 10 | 50% |
| Intermediate risk | 25 | 61% | 10 | 50% |
| ADT prescribed | 14 | 34% | 3 | 15% |
| Median duration of ADT in months (IQR) | 9 (3/18) | 6 (6/8) | ||
| Median age at RT (IQR) | 74 (70/77) | 72 (67/72) | ||
| Median follow-up in months (IQR) | 72 (49/84) | 68 (36/86.5) |