BED of the two SMART regimens (Gy)
| BED (P67.5) | BED (P70) | |
|---|---|---|
| Tumor OTT disregarded (α/β= 10Gy) | 82.7 | 84.8 |
| Tumor OTT taken into account (α/β= 10Gy) | 62.9 | 62.0 |
| Normal tissue (α/β= 5Gy) | 97.9 | 99.7 |
| Normal tissue (α/β= 3Gy) | 118.1 | 119.5 |
Patients with treatment failure
| TNM stage | Failure time (month) | Failure site | Salvage treatment | Living status | Follow-up* (month) |
|---|---|---|---|---|---|
| 1. T1N2M0 | 6 | Bone | CT | Dead | 17 |
| 2. T3N3bM0 | 7 | Liver | CT | Dead | 14 |
| 3. T2N2M0 | 8 | Lung | CT+AT | Living | 14 |
| 4. T1N2M0 | 9 | Bone | CT+AT | Dead | 12 |
| 5. T3N2M0 | 10 | Lung | - | Dead | 17 |
| 6. T1N2M0 | 10 | Liver | CT | Living | 16 |
| 7. T3N2M0 | 10 | Local | RT | Dead | 20 |
| 8. T3N1M0 | 12 | Liver | CT | Dead | 31 |
| 9. T3N2M0 | 13 | Nodal | RT | Living | 37 |
| 10. T1N3bM0 | 13 | Nodal | BT | Living | 26 |
| 11. T4N0M0 | 14 | Liver | - | Dead | 18 |
| 12. T3N1M0 | 21 | Local | - | Dead | 24 |
| 13. T3N1M0 | 22 | Liver & Lung | CT | Living | 33 |
| 14. T3N0M0 | 23 | Local | CRT | Dead | 33 |
| 15. T3N2M0 | 23 | Nodal | CT | Living | 27 |
| 16. T2N2M0 | 24 | Nodal | CRT | Living | 37 |
Distributions of patients in P67_5/P70 study according to the Union for International Cancer Control (UICC) 2002 staging system
| Stage | N0 | N1 | N2 | N3 | Total |
|---|---|---|---|---|---|
| T1 | 6/16 | 13/27 | 11/15 | 3/3 | 33/61 |
| T2 | 3/13 | 15/24 | 23/22 | 3/2 | 44/61 |
| T3 | 2/8 | 15/11 | 18/18 | 3/3 | 38/40 |
| T4 | 2/3 | 3/10 | 11/11 | 1/4 | 17/28 |
| Total | 13/40 | 46/72 | 63/66 | 10/12 | 132/190 |
Acute toxicities of normal organs [n (%)]
| Toxicity | Grade 0 | Grade 1 | Grade 2 | Grade 3 | Grade 4 | p | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| P67.5 | P70 | P67.5 | P70 | P67.5 | P70 | P67.5 | P70 | P67.5 | P70 | ||
| Skin reaction | 6 (4.5) | 7 (3.7) | 92 (69.7) | 137 (72.1) | 27 (20.5) | 37 (19.5) | 7 (5.3) | 9 (4.7) | 0 (0.0) | 0 (0.0) | 0.961 |
| Mucositis | 2 (1.5) | 4 (2.1) | 54 (40.9) | 72 (37.9) | 64 (48.5) | 108 (56.8) | 12 (9.1) | 6 (3.2) | 0 (0.0) | 0 (0.0) | 0.100 |
| Xerostomia | 4 (3.0) | 9 (4.7) | 33 (25.0) | 100 (52.6) | 95 (72.0) | 81 (42.6) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0.000 |
| Pharyngitis-esophagitis | 0 (0.0) | 7 (3.7) | 51 (38.6) | 83 (43.7) | 79 (59.9) | 99 (52.1) | 2 (1.5) | 1 (0.5) | 0 (0.0) | 0 (0.0) | 0.072 |
| Leucopenia | 29 (22.0) | 86 (45.3) | 32 (24.2) | 42 (22.1) | 39 (29.6) | 50 (26.3) | 26 (19.7) | 10 (5.3) | 6 (4.5) | 2 (1.0) | 0.000 |
| Anemia | 66 (55.0) | 175 (92.1) | 44 (33.4) | 14 (7.4) | 18 (13.6) | 1 (0.5) | 4 (3.0) | 0 (0) | 0 (0.0) | 0 (0) | 0.000 |
| Thrombocytopenia | 103 (78.0) | 180 (94.7) | 16 (12.1) | 7 (3.7) | 5 (3.8) | 2 (1.1) | 5 (3.8) | 1 (0.5) | 3 (2.3) | 0 (0) | 0.000 |
Patients’ characteristics
| Characteristics | P67.5 study | P70 study | p | ||
|---|---|---|---|---|---|
| n. | %. | n. | %. | ||
| Age (median) | 15–75 | (47) | 10–81 | (44) | 0.527 |
| Gender | |||||
| Male | 95 | 72.0 | 144 | 75.8 | 0.441 |
| Female | 37 | 28.0 | 46 | 24.2 | |
| Region | |||||
| Northern China | 110 | 83.3 | 159 | 83.7 | 0.933 |
| Southern China | 22 | 16.7 | 31 | 16.3 | |
| KPS | |||||
| 90–100 | 105 | 79.5 | 133 | 70.0 | 0.055 |
| 70–80 | 27 | 20.5 | 57 | 30.0 | |
| Pathology | |||||
| WHO type I | 2 | 1.5 | 3 | 1.6 | 0.964 |
| WHO type II | 130 | 98.5 | 187 | 98.4 | |
| UICC 2002 Stage | |||||
| I | 6 | 4.5 | 16 | 8.4 | 0.045 |
| II | 31 | 68 | 51.5 | 37.4 | |
| III | 23.5 | 64 | 71 | 33.7 | |
| IVa-b | 27 | 20.5 | 39 | 20.5 | |
Dosimetric data of organs at risk
| Mean value (Range) | p | ||
|---|---|---|---|
| P67.5 study | P70 study | ||
| Beam-on time (s) | 413.8 (336.0–521.7) | 455.8 (358.0–696.0) | 0.674 |
| Couch travel (cm) | 21.4 (18.0–27.0) | 22.6 (17.0–28.7) | 0.000 |
| pGTVnx Dmean | 70.2 (69.2–72.6) | 72.3 (70.4–75.6) | 0.000 |
| pGTVnd Dmean | 70.1 (69.2–72.7) | 72.3 (70.1–75.6) | 0.000 |
| PTV1 Dmean | 64.9 (63.1–67.3) | 64.6 (62.1–70.5) | 0.083 |
| PTV2 Dmean | 56.7 (55.7–59.8) | 57.4 (54.7–61.7) | 0.000 |
| Brainstem Dmax | 51.1 (35.9–69.1) | 54.5 (41.6–71.9) | 0.000 |
| Spinal cord Dmax | 40.6 (35.2–51.1) | 41.5 (33.7–51.8) | 0.003 |
| Optic nerve Dmax | |||
| Left | 29.0 (3.9–70.5) | 38.3 (9.7–72.2) | 0.000 |
| Right | 28.3 (4.6–70.8) | 39.3 (9.2–72.9) | 0.000 |
| Eyeball Dmax | |||
| Left | 19.4 (4.0–38.9) | 29.6 (10.0–65.4) | 0.000 |
| Right | 19.1 (5.3–38.8) | 29.6 (11.2–57.7) | 0.000 |
| Lens Dmax | |||
| Left | 3.2 (2.0–5.3) | 4.1 (2.2–8.1) | 0.000 |
| Right | 3.2 (2.2–8.3) | 4.1 (2.2–8.3) | 0.000 |
| TMJ Dmean | |||
| Left | 33.7 (22.6–60.4) | 38.7 (22.9–58.5) | 0.000 |
| Right | 33.1 (22.5–64.7) | 38.2 (21.1–51.8) | 0.000 |
| Inner ear Dmean | |||
| Left | 45.4 (27.4–67.1) | 43.1 (12.3–58.0) | 0.055 |
| Right | 44.7 (26.3–61.7) | 44.4 (11.6–65.2) | 0.815 |
| Parotid gland Dmean | |||
| Left | 30.8 (25.2–39.9) | 31.2 (23.8–55.1) | 0.334 |
| Right | 30.7 (22.9–65.2) | 31.0 (22.0–47.9) | 0.636 |
| Oral cavity Dmean | 34.2 (26.6–42.0) | 38.8 (11.5–50.2) | 0.000 |
| L-E-T Dmean | 32.7 (24.2–38.8) | 38.7 (19.1–49.6) | 0.000 |
Summary of reported prospective studies on simultaneous modulated accelerated radiation therapy (SMART) for nasopharyngeal carcinoma (NPC)
| Author | N | T3-4 tumor n (%) | Positive node n (%) | Fractionation patterns for GTV | LCR (%) | ||||
|---|---|---|---|---|---|---|---|---|---|
| Fraction | Prescription dose (Gy) | Fraction dose (Gy) | BED* (Gy) OTT disregarded | BED* (Gy) | |||||
| Lee SW (2005)12 | 20 | 8 (40) | 18 (90) | 30 | 72 | 2.4 | 89.3 | 69.5 | 88.0 (2-y) |
| Lin SJ (2009)13 | 323 | 260 (80.5) | 293 (90.7) | 30 / 31 | 66 / 69.8 | 2.2 / 2.25 | 80.5 / 85.4 | 60.7 / 63.8 | 95.0 (3-y LRFS) |
| RTOG0225 (2009)14 | 68 | 23 (33.8) | 50 (73.5) | 33 | 70 | 2.12 | 84.8 | 62.0 | 92.6 (2-y) |
| Xiao WW (2011)15 | 81 | 81 (100) | 56 (69.1) | 30 | 68 | 2.27 | 83.4 | 63.6 | 94.9 (3-y) |
| Bakst RL (2011)16 | 25 | 16 (64) | 20 (80) | 30 | 70.2 | 2.34 | 86.6 | 66.8 | 91.0 (3-y) |
| Wang RS (2013)17 | 300 | 214 (71.3) | 277 (92.3) | 30–32 | 68–72 | 2.25–2.27 | 83.4–88.2 | 63.6–66.0 | 94.0 (4-y) |
| Author (2014)3 | 190 | 68 (35.8) | 150 (78.9) | 33 | 70 | 2.12 | 84.8 | 62.0 | 96.1 (2-y LRFS) |
| Current study | 132 | 55 (41.7) | 119 (90.2) | 30 | 67.5 | 2.25 | 82.7 | 62.9 | 96.7 (2-y LRFS) |