Table 2.
Dosimetric results of Anon Study of prone PBI (100 patients, 101 plans) compared with those from William Beaumont supine PBI (94 plans) [8]
| Dosimetric characteristics of the study population | ||||||
|---|---|---|---|---|---|---|
| Dosimetric characteristics | Anon Study Mean value | Beaumont Mean value | Anon Study Median value | Beaumont Median value | Anon Study Range | Beaumont Range |
| PTV_EVAL (cc) | 200.8 | 268.1 | 161.7 | 265.6 | 46.8–900.3 | 61.8–623.0 |
| Whole breast volume (cc) | 1135 | 1584 | 1012 | 1499 | 262–3493 | 481–3417 |
| V5/WBV | 58% | 77% | 58% | 77% | 29%–99% | 46%–94% |
| V10/WBV | 54% | 72% | 53% | 73% | 27%–96% | 43%–91% |
| V25/WBV | 50% | 62% | 48% | 63% | 23%–93% | 37%–92% |
| V50/WBV | 45% | 49% | 43% | 50% | 18%–80% | 31%–61% |
| V75/WBV | 39% | 39% | 38% | 40% | 14%–76% | 26%–53% |
| V100/WBV | 24% | 24% | 24% | 24% | 5%–49% | 2%–39% |
| Maximum dose (Ratio of PD) | 1.08 | 1.10 | 1.07 | 1.10 | 1–1.32 | 1.05–1.27 |
| CTV coverage | ||||||
| 100% IDL | 98% | 95% | 98% | 99% | 55.4%–100% | 54%–100% |
| 95% IDL | 99% | 99% | 99% | 100% | 84.5%–100% | 97.5%–100% |
| PTV coverage | ||||||
| 95% IDL | 97% | 98% | 97% | 100% | 84.5%–100% | 92.5%–100% |
| Ipsilateral breast coverage (cc) | ||||||
| 100% IDL | 244.6 | 381.8 | 205.9 | 360.1 | 9.3–1146.8 | 31.4–885.0 |
| 75% IDL | 432.3 | 627.2 | 365.9 | 596 | 122.5–1563.3 | 152.0–1621.0 |
| 50% IDL | 494.2 | 783.1 | 422.8 | 754.7 | 146.1–1987.5 | 221.7–1881.8 |
| 25% IDL | 556.5 | 977.5 | 467.5 | 951.8 | 166.9–2306.3 | 263.0–2176.7 |
| PTV/total breast volume % | 18% | 17% | 17% | 17% | 6%–46% | 8%–27% |
| Dmax (cGy)* | 3250 | 4208 | 3210 | 4232 | 3000–3960 | 3668–4880 |
*
Anon U prescribed dose: 6Gy x 5 daily fractions, total dose 30Gy in 10 days
Beaumont prescribed dose: 3.85Gy x 10 BID fractions, total dose 38.5Gy in 5 days