Table 2.
Dosimetric comparison of Vienna-type plan using only parallel needles versus Venezia plan using both parallel and oblique needles
| EQD2 (Gy) | Patient no. 1 HR-CTV = 61 cc IR-CTV = 116 cc |
Patient no. 2 HR-CTV = 96 cc IR-CTV = 171 cc |
Patient no. 3 HR-CTV = 57 cc IR-CTV = 110 cc |
Patient no. 4 HR-CTV = 64 cc IR-CTV = 135 cc |
Patient no. 5 HR-CTV = 92 cc IR-CTV = 158 cc |
P-value | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Parallel needles | Parallel and oblique needles | Parallel needles | Parallel and oblique needles | Parallel needles | Parallel and oblique needles | Parallel needles | Parallel and oblique needles | Parallel needles | Parallel and oblique needles | ||
| D90 HR-CTV (EQD210, Gy) |
84.0 | 90.3 | 81.5 | 83.2 | 77.4 | 85.9 | 83.5 | 90.0 | 78.1 | 85.3 | 0.006 |
| D90 IR-CTV (EQD210, Gy) |
68.4 | 72.3 | 67.0 | 68.7 | 69.1 | 70.6 | 64.3 | 67.1 | 64.4 | 66.3 | 0.006 |
| D2cc rectum (EQD23, Gy) |
68.1 | 74.7 | 72.0 | 72.5 | 66.0 | 67.6 | 74.5 | 73.9 | 67.6 | 68.7 | NS |
| D2cc bladder (EQD23, Gy) |
90.1 | 87.5 | 84.1 | 87.9 | 76.1 Dose rate limit 0.6 Gy/h |
77.7 Dose rate limit 0.6 Gy/h |
76.4 | 77.4 | 83.7 Dose rate limit 0.6 Gy/h |
80.8 Dose rate limit 0.6 Gy/h |
NS |
| D2cc sigmoid (EQD23, Gy) |
51.4 | 53.1 | 52.4 | 52.3 | 56.9 | 57.2 | 61.7 | 61.7 | 75.1 | 74.3 | NS |
| D2cc bowel (EQD23, Gy) |
72.7 | 73.6 | 74.8 | 75.1 | 57.6 | 57.7 | 75.0 | 74.7 | 55.6 | 55.6 | NS |
| Vaginal TRAK/total TRAK ratio | 54% | 44% | 32% | 28% | 34% | 28% | 13% | 11% | 45% | 34% | 0.01 |
| TRAK (cGy/m2) |
2.51 | 2.64 | 2.88 | 2.94 | 1.55 | 1.74 | 2.55 | 2.56 | 2.88 | 2.83 | NS |
| Conformation number | 0.50 | 0.51 | 0.59 | 0.58 | 0.52 | 0.61 | 0.54 | 0.61 | 0.50 | 0.54 | 0.09 |
Italic characters represent dosimetric factor that reached pre-established constraint first during optimization process, NS – not significant