Table 1.
Clinical characteristics of the patients and factors associated with residual tumors at the end of IMRT
| Characteristic | Group | Patients without residual tumor ( n = 212) | Patients with residual tumor ( n = 142) | Χ 2 | P |
|---|---|---|---|---|---|
| Age (y) | <50 | 138 (59.7%*) | 93 (40.3%) | 0.006 | 0.938 |
| ≥50 | 74 (60.2%) | 49 (39.8%) | |||
| T-stage | T3 | 42 (66.7%) | 21 (33.3%) | 1.47 | 0.226 |
| T4 | 170 (58.4%) | 121 (41.6%) | |||
| N-stage | N0-1 | 120 (68.2%) | 56 (31.8%) | 10.02 | 0.002 |
| N2-3 | 92 (51.7%) | 86 (48.3%) | |||
| Overall stage | III | 38 (66.7%) | 19 (33.3%) | 1.30 | 0.254 |
| IV | 174 (58.6%) | 123 (41.4%) | |||
| Chemotherapy | Yes | 197 (59.0%) | 137 (41.0%) | 2.02 | 0.156 |
| No | 15 (75.0%) | 5 (25.0%) | |||
| GTVnx V95% | <95% | 28 (37.3%) | 47 (62.7%) | 20.15 | <0.001 |
| ≥95% | 184 (65.9%) | 95 (34.1%) | |||
| Prescribed dose | ≤73.92 Gy | 201 (63.0%) | 118 (37.0%) | 13.09 | <0.001 |
| >73.92 Gy | 11 (31.4%) | 24 (68.6%) |
*Percentage = the number before the bracket divided by the numbers of before the bracket in the same line of column 3 plus column 4.
GTVnx: Primary gross target volume; GTVnx V95%: percentage volume of GTVnx receiving 95% prescribed doses.