Table 4 Radiation doses to the PGTVnx and brain stem for the patients with locally-advanced nasopharyngeal carcinoma stratified by T classification and the distance from the primary tumor to the brain stem (Dbs)
Mean (range) | Dbs ≤ 4.7 mm | Dbs > 4.7 mm | 7th AJCC T3 | 7th AJCC T4 |
|---|---|---|---|---|
Tumor volume | ||||
GTV-P (ml) | 63.0 (16.5–204.8) | 33.6 (5.9–164.0) | 25.3 (6.3–73) | 49.2 (5.9–204.8) |
SV-PGTVnx (ml) | 0.52 (0–12.4) | 0.002 (0–0.2) | 0.02 (0–0.44) | 0.24 (0–12.4) |
PGTVnx | ||||
Dmin (Gy) | 46.4 (21.9–66.6) | 63.1 (21.7–74) | 62.5 (38.6–73.6) | 55.4 (21.7–74) |
Dmean (Gy) | 75.4 (65.6–83.9) | 75.8 (67.6–84.1) | 76.2 (71.0–81.1) | 75.6 (65.6–84.1) |
Dmax (Gy) | 80.3 (69.5–88.7) | 79.3 (70.9–88.8) | 79.8 (76–84.1) | 79.7 (69.5–88.8) |
D95 % (Gy) | 69.0 (49.9–80.5) | 73.1 (64.9–81) | 72.8 (57.9–78.4) | 71.2 (49.9–81) |
V95 % (Gy) | 94.8 (84.4–98.8) | 99.1 (90–100) | 98.8 (90.2–100) | 97.2 (84.4–100) |
Brain stem | ||||
Dmax (Gy) | 54.1 (45.1–68.4) | 51.8 (41.7–68.8) | 50.9 (42.7–56.3) | 52.5 (41.7–68.8) |
D1 % | 49.1 (38.8–59) | 46.7 (34.8–58.6) | 46.3 (34.8–50.6) | 47.9 (36.9–59.9) |
D1cc (Gy) | 47.6 (36.7–56.7) | 45.3 (35.4–52.4) | 44.9 (35.4–49.8) | 46.4 (35.7–56.7) |
D1/3 (Gy) | 39.9 (28.7–51.2) | 37.2 (22.8–53.8) | 37.4 (22.8–53.8) | 38.4 (26.1–51.2) |
Dmean (Gy) | 36.4 (25.8–49.8) | 31.6 (19.7–41.7) | 31.6 (19.7–37.5) | 33.8 (21.1–49.8) |