Table 4.
Factors affecting survival outcome for each risk groups in multivariate analysis
| Low-risk group (n=5,684) |
High-risk group (n=2,196) |
|||||||
|---|---|---|---|---|---|---|---|---|
| Alive (n=5,198) | Death (n=486) | Adjusted HR (95% CI) | p-value | Alive (n=1,816) | Death (n=380) | Adjusted HR (95% CI) | p-value | |
| Adjuvant chemotherapy | ||||||||
| Without AC | 2,616 (89.4) | 310 (10.6) | Reference | 618 (71.6) | 245 (28.4) | Reference | ||
| With AC | 2,582 (93.6) | 176 (6.4) | 0.74 (0.61-0.89) | 0.002 | 1,198 (89.9) | 135 (10.1) | 0.76 (0.38-0.59) | < 0.001 |
| No. of risks | ||||||||
| 0 | 5,198 (91.5) | 486 (8.6) | - | - | - | |||
| 1 | - | - | - | - | 1,600 (84.2) | 300 (15.8) | Reference | |
| 2 | - | - | - | - | 206 (73.6) | 74 (26.4) | 1.26 (0.97-1.65) | 0.088 |
| 3 or 4 | - | - | - | - | 10 (62.5) | 6 (37.5) | 1.76 (0.78-3.99) | 0.175 |
| Sex | ||||||||
| Male | 3,036 (90.4) | 321 (9.6) | Reference | 1,060 (82.3) | 228 (17.7) | Reference | ||
| Female | 2,162 (92.9) | 165 (7.1) | 0.66 (0.54-0.80) | < 0.001 | 756 (83.3) | 152 (16.7) | 0.68 (0.55-0.84) | < 0.001 |
| Age (yr) | ||||||||
| ≤ 45 | 272 (97.8) | 6 (2.2) | Reference | 89 (95.7) | 4 (4.3) | Reference | ||
| > 45 and ≤ 70 | 2,911 (95.7) | 132 (4.3) | 1.94 (0.85-4.39) | 0.114 | 962 (91.4) | 90 (8.6) | 1.89 (0.69-5.16) | 0.215 |
| > 70 | 2,015 (85.3) | 348 (14.7) | 5.74 (2.55-12.93) | < 0.001 | 765 (72.8) | 286 (27.2) | 4.90 (1.81-13.27) | 0.002 |
| BMI (n=7,823) | ||||||||
| ≤ 18 | 226 (82.8) | 47 (17.2) | 1.67 (1.23-2.27) | 0.001 | 91 (67.4) | 44 (32.6) | 1.95 (1.40-2.71) | < 0.001 |
| > 18 and ≤ 25 | 3,382 (90.6) | 353 (9.5) | Reference | 1,232 (83.1) | 250 (16.9) | Reference | ||
| > 25 | 1,565 (95.2) | 79 (4.8) | 0.56 (0.44-0.72) | < 0.001 | 478 (86.3) | 76 (13.7) | 1.02 (0.78-1.32) | 0.900 |
| Type of institution | ||||||||
| Tertiary hospital | 2,851 (92.2) | 242 (7.8) | Reference | 816 (83.4) | 163 (16.6) | Reference | ||
| General hospital | 2,034 (90.0) | 227 (10.0) | 1.28 (1.06-1.54) | 0.009 | 941 (82.0) | 206 (18.0) | 1.13 (0.91-1.39) | 0.249 |
| Hospital or clinic | 310 (94.8) | 17 (5.2) | 0.78 (0.48-1.28) | 0.330 | 59 (84.3) | 11 (15.7) | 1.75 (0.94-3.24) | 0.078 |
| ASA | ||||||||
| I-II | 4,446 (93.4) | 312 (6.6) | Reference | 1,479 (86.8) | 224 (13.2) | Reference | ||
| III | 732 (81.6) | 165 (18.4) | 2.11 (1.73-2.57) | < 0.001 | 313 (68.9) | 141 (31.1) | 1.75 (1.40-2.20) | < 0.001 |
| IV | 20 (69.0) | 9 (31.0) | 3.33 (1.65-6.74) | 0.001 | 24 (61.5) | 15 (38.5) | 1.67 (0.95-2.92) | 0.074 |
| Emergency operation | ||||||||
| No | 5,162 (91.5) | 478 (8.5) | - | 1,399 (86.1) | 225 (13.9) | Reference | ||
| Yes | 36 (81.8) | 8 (18.2) | - | - | 417 (72.9) | 155 (27.1) | 1.82 (1.45-2.28) | < 0.001 |
| Others | 36 (81.8) | 8 (18.2) | 27 (77.1) | 8 (22.9) | ||||
| Perforated/Obstructive | - | - | 390 (72.6) | 147 (27.4) | ||||
| Proximal or distal resection margin (n=6,470) | ||||||||
| Negative | 4,622 (91.8) | 415 (8.2) | 1,122 (82.4) | 239 (17.6) | ||||
| Positive | - | - | 63 (87.5) | 9 (12.5) | ||||
| LVP invasion (n=1,369) | ||||||||
| No | 558 (89.3) | 67 (10.7) | 93 (81.6) | 21 (18.4) | ||||
| Yes | - | - | 525 (83.3) | 105 (16.7) | ||||
| Lymph node (n=7,494) | ||||||||
| < 12 | - | - | 425 (83.2) | 86 (16.8) | ||||
| ≥ 12 | 5,082 (91.5) | 473 (8.5) | 1,199 (84.0) | 229 (16.0) | ||||
| Differentiation (n=3,488) | ||||||||
| Well | 346 (89.9) | 39 (10.1) | 145 (77.5) | 42 (22.5) | ||||
| Moderate | 1,753 (89.4) | 209 (10.7) | 650 (81.5) | 148 (18.6) | ||||
| Poorly+others | - | - | 126 (80.8) | 30 (19.2) | ||||
| Stage (n=4,392) | ||||||||
| IIA | 3,099 (92.9) | 238 (7.1) | 381 (84.3) | 71 (15.7) | ||||
| IIB-IIC | - | - | 514 (85.2) | 89 (14.8) | ||||
The HR for the low-risk group was adjusted for sex, age, BMI, type of institutions, ASA, and emergency operation. The HR for the high-risk group was adjusted for number of risk, sex, age, BMI, type of institutions, ASA, and emergency operation. HR, hazard ratio; CI, confidence interval; AC, adjuvant chemotherapy; BMI, body mass index; ASA, American Society of Anesthesiologists; LVP, lymphovascular or perineural.