Table 1 Clinicopathological characteristics of patients in the training, internal validation and external validation cohorts (N(%))
Characteristics | SEER | SEER | HUST-JU | ||||||
|---|---|---|---|---|---|---|---|---|---|
Training cohort | P | Internal validation cohort | P | External validation cohort | P | ||||
Alive | Dead | Â | Alive | Dead | Â | Alive | Dead | Â | |
N = 163 | N = 668 | N = 55 | N = 301 | N = 21 | N = 42 | ||||
Age | |||||||||
 < 60 | 88(53.98) | 265(39.67) | 0.001 | 31(56.36) | 111(36.88) | 0.007 | 14(66.67) | 8(19.05) | < 0.001 |
 ≥60 | 75(46.02) | 403(60.33) |  | 24(43.64) | 190(63.12) |  | 7(33.33) | 34(80.95) |  |
Sex | |||||||||
 Male | 84(51.53) | 358(53.69) | 0.637 | 25(45.45) | 165(54.82) | 0.202 | 11(52.38) | 23(54.76) | 0.861 |
 Female | 79(48.47) | 310(46.41) |  | 30(54.55) | 136(45.18) |  | 10(47.62) | 19(45.24) |  |
Tumor location | |||||||||
 Colon | 111(71.78) | 544(81.44) | 0.001 | 44(80.00) | 250(83.06) | 0.584 | 12(57.14) | 39(92.86) | < 0.001 |
 Rectum | 52(28.22) | 124(18.56) |  | 11(20.00) | 51(16.94) |  | 9(42.86) | 3(7.14) |  |
Differentiation | |||||||||
 Well | 7(4.29) | 24(3.59) | 0.160 | 2(3.63) | 13(4.32) | 0.162 | 4(19.05) | 1(2.38) | 0.245 |
 Moderately | 123(75.46) | 444(66.47) |  | 44(80.00) | 210(69.77) |  | 13(61.90) | 29(69.05) |  |
 Poorly | 22(13.50) | 147(22.01) | 7(12.73) | 56(18.60) | 3(14.29) | 10(23.36) | |||
 Undifferentiated | 3(1.85) | 35(5.24) | 2(3.64) | 17(5.65) | 0(0) | 1(2.38) | |||
 Unknow | 8(4.90) | 18(2.69) | 0(0) | 5(1.66) | 1(4.76) | 1(2.38) | |||
Histological type | |||||||||
 Adenocarcinoma | 147(90.18) | 579(86.68) | 0.619 | 51(92.73) | 261(86.72) | 0.694 | 19(90.48) | 37(88.10) | 0.574 |
 Mucinous adenocarcinoma | 6(3.68) | 48(7.19) |  | 0(0) | 20(6.64) |  | 1(4.76) | 5(11.90) |  |
 Signet ring cell carcinoma | 0(0) | 2(0.30) | 0(0) | 1(0.33) | 0(0) | 0(0) | |||
 Other | 10(6.14) | 39(5.83) | 4(7.27) | 19(12.31) | 1(4.76) | 0(0) | |||
Size, mm | |||||||||
 <  55 | 100(61.35) | 328(49.10) | 0.005 | 35(63.64) | 161(53.49) | 0.165 | 17(80.95) | 25(59.52) | 0.072 |
 ≥ 55 | 63(38.65) | 340(50.90) |  | 20(36.36) | 140(46.51) |  | 4(19.05) | 17(40.48) |  |
TNM stage | |||||||||
 IVB | 163(100) | 668(100) |  | 55(100) | 301(100) |  | 21(100) | 42(100) | |
 T1 | 2(1.23) | 3(0.45) | 0(0) | 0(0) | 0(0) | 0(0) | 0.075 | ||
T stage | |||||||||
 T2 | 6(3.68) | 13(1.95) |  | 0(0) | 4(1.33) |  | 0(0) | 0(0) |  |
 T3 | 108(66.26) | 352(52.69) | 34(61.82) | 152(50.50) | 15(68.12) | 20(47.62) | |||
 T4 | 47(28.83) | 300(44.91) | 21(38.18) | 145(48.17) | 6(31.88) | 22(52.38) | |||
 N0 | 32(19.63) | 78(11.68) | < 0.001 | 7(12.73) | 26(8.64) | 0.029 | 3(14.29) | 2(4.76) | 0.001 |
N stage | |||||||||
 N1 | 78(47.85) | 233(34.88) |  | 27(49.09) | 109(36.21) |  | 4(19.05) | 5(11.90) |  |
 N2 | 53(32.52) | 357(53.44) | 21(38.18) | 166(55.15) | 14(66.66) | 35(83.34) | |||
M stage | |||||||||
 M1a | 0(0) | 0(0) | – | 0(0) | 0(0) | – | 0(0) | 0(0) | – |
 M1b | 163(100) | 668(100) | 1 | 55(100) | 301(100) | 1 | 21(100) | 42(100) | 1 |
Radiotherapy | |||||||||
 Yes | 29(17.79) | 31(4.64) | < 0.001 | 2(3.64) | 9(2.99) | 0.800 | 4(19.05) | 2(4.76) | 0.071 |
 None/Unknown | 143(82.21) | 637(95.36) |  | 53(96.36) | 292(97.01) |  | 17(80.95) | 40(95.24) |  |
Chemotherapy | |||||||||
 Yes | 150(92.02) | 446(66.77) | < 0.001 | 48(87.27) | 194(64.45) | 0.001 | 17(80.95) | 24(57.14) | 0.047 |
 None/Unknown | 13(7.98) | 222(33.23) |  | 7(12.73) | 107(35.55) |  | 4(19.05) | 18(42.86) |  |
No. of sampled LNs Median (IR) | 16(11) | 16(10) | 0.219 | 16(10) | 16(10) | 0.821 | 20(9) | 16(9) | 0.031 |
No. of Positive LNs Median (IR) | 2(5) | 4(7) | < 0.001 | 4(5) | 3(7) | 0.001 | 2(5) | 2(7) | 0.570 |
Primary surgery | |||||||||
 Yes | 163(100) | 667(99.85) | 0.622 | 53(100) | 300(99.67) | 0.670 | 21(100) | 41(97.62) | 0.484 |
 No | 0 | 1(0.15) |  | 0 | 1(0.33) |  | 0(0) | 1(2.38) |  |
Metastatic surgery | |||||||||
 Yes | 49(30.06) | 118(17.66) | < 0.0001 | 11(20.00) | 59(19.60) | 0.946 | 5(23.81) | 4(9.52) | 0.131 |
 No | 114(69.94) | 550(82.34) |  | 44(80.80) | 242(80.40) |  | 16(76.19) | 38(90.48) |  |
CSS | |||||||||
 Yes | 91 | 491 | 0.211 | 25 | 217 | 0.236 | 11 | 37 | 0.025 |
 No | 72 | 177 |  | 30 | 84 |  | 10 | 4 |  |