Table 1 Baseline characteristics of the population stratified by pathological types.
|  | Adenocarcinoma n = 54,174 | Mucinous n = 3,813 | Signet-ring cell n = 664 | p-value |
|---|---|---|---|---|
Age (year) | 64.37 ± 13.46 | 64.63 ± 14.47 | 62.10 ± 15.77 |  < 0.001 |
Race (%) |  < 0.001 | |||
 White | 40,439 (74.65) | 3016 (79.10) | 525 (79.07) |  |
 Black | 6434 (11.88) | 397 (10.41) | 67 (10.09) |  |
 Others | 7301 (13.48) | 400 (10.49) | 72 (10.84) |  |
Marital status (%) | 0.007 | |||
 Single | 9092 (16.78) | 633 (16.60) | 147 (22.14) |  |
 Married | 28,442 (52.50) | 2020 (52.98) | 332 (50.00) |  |
 Other | 16,640 (30.72) | 1160 (30.42) | 185 (27.86) |  |
Sex (%) |  < 0.001 | |||
 Female | 25,521 (47.11) | 1955 (51.27) | 326 (49.10) |  |
 Male | 28,653 (52.89) | 1858 (48.73) | 338 (50.90) |  |
Location (%) |  < 0.001 | |||
 Right | 20,831 (38.45) | 2430(63.73) | 410 (61.75) |  |
 Left | 15,047 (27.78) | 662 (17.36) | 106(15.96) |  |
 Rectum | 16,961 (31.31) | 592 (15.53) | 123 (18.52) |  |
 Unknown | 1335 (2.46) | 129 (3.38) | 25 (3.77) |  |
Grade (%) |  < 0.001 | |||
 Well-differentiated | 3891 (7.18) | 457 (11.99) | 6 (0.90) |  |
 Moderately-differentiated | 35,816 (66.11) | 2122 (55.65) | 31 (4.67) |  |
 Poorly-differentiated | 6802 (12.56) | 576(15.11) | 414 (62.35) |  |
 Undifferentiated | 1193 (2.20) | 179 (4.69) | 99 (14.91) |  |
 Unknown | 6472 (11.95) | 479 (12.56) | 114 (17.17) |  |
AJCC 7th, T stage (%) |  < 0.001 | |||
 T1 | 7690 (14.20) | 130 (3.41) | 27 (4.07) |  |
 T2 | 4749 (8.77) | 254 (6.66) | 22 (3.31) |  |
 T3 | 18,248 (33.68) | 1402 (36.77) | 158 (23.80) |  |
 T4 | 5957 (11.00) | 949 (24.89) | 247 (37.20) |  |
 Unknown | 17,530 (32.36) | 1078 (28.27) | 210 (31.63) |  |
AJCC 7th, N stage (%) |  < 0.001 | |||
 N0 | 21,906(40.44) | 1507 (39.52) | 152 (22.89) |  |
 N1 | 10,925 (20.17) | 743 (19.49) | 113 (17.02) |  |
 N2 | 5240 (9.67) | 559 (14.66) | 210 (31.63) |  |
 Unknown | 16,103 (29.72) | 1004 (26.33) | 189 (28.46) |  |
AJCC 7th, M stage (%) |  < 0.001 | |||
 M0 | 31,505 (58.16) | 2130 (55.86) | 299 (45.03) |  |
 M1 | 8430 (15.56) | 793 (20.80) | 211 (31.78) |  |
 Unknown | 14,239 (26.28) | 890 (23.34) | 154 (23.19) |  |
Stages |  < 0.001 | |||
 I | 9528 (17.59) | 287 (7.53) | 24 (3.61) |  |
 II | 9437 (17.42) | 910(23.87) | 68 (10.24) |  |
 III | 11,308 (20.87) | 895 (23.47) | 193 (29.07) |  |
 IV | 8430 (15.56) | 783 (20.80) | 211 (31.78) |  |
 Unknown | 15,471 (28.56) | 928 (24.34) | 168 (25.30) |  |
CEA (%) |  < 0.001 | |||
 Negative | 17,466 (32.24) | 1053 (27.62) | 177 (26.66) |  |
 Positive | 15,733 (29.04) | 1269 (33.28) | 251 (37.80) |  |
 Unknown | 20,975 (38.72) | 1491 (39.10) | 236 (35.54) |  |
Perineural invasion (%) |  < 0.001 | |||
 Negative | 38,640 (71.33) | 2523 (66.17) | 287 (43.22) |  |
 Positive | 4898 (9.04) | 293 (7.68) | 124 (18.67) |  |
 Unknown | 10,636 (19.63) | 997 (26.15) | 253 (38.10) |  |
Liver metastases (%) |  < 0.001 | |||
 No | 44,557 (82.25) | 3342 (87.65) | 600(90.36) |  |
 Yes | 8541 (15.77) | 407 (10.67) | 49 (7.38) |  |
 Unknown | 1076 (1.99) | 64 (1.68) | 15 (2.26) |  |
Bone metastases (%) | 0.003 | |||
 No | 52,340 (96.61) | 3710 (97.30) | 637 (95.93) |  |
 Yes | 616 (1.14) | 36 (0.94) | 16 (2.41) |  |
 Unknown | 1218 (2.25) | 67 (1.76) | 11 (1.66) |  |
Brain metastases (%) | 0.020 | |||
 No | 52,772 (97.41) | 3742 (98.14) | 652 (98.19) |  |
 Yes | 172 (0.32) | 5 (0.13) | 3 (0.45) |  |
 Unknown | 1230 (2.27) | 66 (1.73) | 9 (1.36) |  |
Lung metastases (%) |  < 0.001 | |||
 No | 49,927 (92.16) | 3605 (94.54) | 635 (95.63) |  |
 Yes | 2959 (5.46) | 134 (3.51) | 16 (2.41) |  |
 Unknown | 1288 (2.38) | 74 (1.94) | 13 (1.96) |  |
Surgery (%) |  < 0.001 | |||
 No | 8783 (16.21) | 370 (9.70) | 148 (22.29) |  |
 Yes | 45,248 (83.52) | 3437 (90.14) | 515 (77.56) |  |
 Unknown | 143 (0.26) | 6 (0.16) | 1 (0.15) |  |
Chemotherapy |  < 0.001 | |||
 No/Unknown | 29,095 (53.71) | 1869 (49.02) | 240 (36.14) |  |
 Yes | 25,079 (46.29) | 1944 (50.98) | 424 (63.86) |  |
Radiotherapy |  < 0.001 | |||
 No/Unknown | 45,089 (83.23) | 3408 (89.38) | 574 (86.45) |  |
 Yes | 9085 (16.77) | 405 (10.62) | 90 (13.55) |  |
