Table 1.
Clinical and pathological characteristics of the training cohort and internal validation
| Variables | Total (n = 282) | Training cohort (n = 141) | Internal validation (n = 141) | p-Value | Statistic |
|---|---|---|---|---|---|
| Sex, n (%) | 0.408 | 0.686 | |||
| Male | 239 (84.8) | 122 (86.5) | 117 (83) | ||
| Female | 43 (15.2) | 19 (13.5) | 24 (17) | ||
| Age, n (%) | 0.999 | 0 | |||
| < 65 years | 194 (68.8) | 97 (68.8) | 97 (68.8) | ||
| ≥ 65 years | 88 (31.2) | 44 (31.2) | 44 (31.2) | ||
| Smoker, n (%) | 0.201 | 1.632 | |||
| No | 90 (31.9) | 40 (28.4) | 50 (35.5) | ||
| Yes | 192 (68.1) | 101 (71.6) | 91 (64.5) | ||
| Drinker, n (%) | 0.059 | 3.572 | |||
| No | 95 (33.7) | 40 (28.4) | 55 (39) | ||
| Yes | 187 (66.3) | 101 (71.6) | 86 (61) | ||
| Location, n (%) | 0.468 | 1.52 | |||
| Up | 39 (13.8) | 18 (12.8) | 21 (14.9) | ||
| Middle | 108 (38.3) | 59 (41.8) | 49 (34.8) | ||
| Low | 135 (47.9) | 64 (45.4) | 71 (50.4) | ||
| Differentiation, n (%) | 0.495 | 1.408 | |||
| Well | 24 (8.5) | 14 (9.9) | 10 (7.1) | ||
| Middle | 158 (56.0) | 81 (57.4) | 77 (54.6) | ||
| Poor | 100 (35.5) | 46 (32.6) | 54 (38.3) | ||
| Surgical margin, n (%) | 0.122 | Fisher | |||
| Negative | 278 (98.6) | 137 (97.2) | 141 (100) | ||
| Positive | 4 (1.4) | 4 (2.8) | 0 (0) | ||
| Nerve invasion, n (%) | 0.424 | 0.638 | |||
| Negative | 235 (83.3) | 115 (81.6) | 120 (85.1) | ||
| Positive | 47 (16.7) | 26 (18.4) | 21 (14.9) | ||
| Lymph, vascular invasion, n (%) | 0.999 | 0 | |||
| Negative | 258 (91.5) | 129 (91.5) | 129 (91.5) | ||
| Positive | 24 (8.5) | 12 (8.5) | 12 (8.5) | ||
| cT, n (%) | 0.145 | 5.393 | |||
| 2 | 19 (6.7) | 9 (6.4) | 10 (7.1) | ||
| 3 | 220 (78.0) | 109 (77.3) | 111 (78.7) | ||
| 4a | 23 (8.2) | 16 (11.3) | 7 (5) | ||
| 4b | 20 ( 7.1) | 7 (5) | 13 (9.2) | ||
| cN, n (%) | 0.155 | Fisher | |||
| 0 | 6 (2.1) | 5 (3.5) | 1 (0.7) | ||
| 1 | 100 (35.5) | 55 (39) | 45 (31.9) | ||
| 2 | 139 (49.3) | 66 (46.8) | 73 (51.8) | ||
| 3 | 37 (13.1) | 15 (10.6) | 22 (15.6) | ||
| ypT, n (%) | 0.338 | Fisher | |||
| 0 | 113 (40.1) | 48 (34) | 65 (46.1) | ||
| 1 | 36 (12.8) | 19 (13.5) | 17 (12.1) | ||
| 2 | 56 (19.9) | 31 (22) | 25 (17.7) | ||
| 3 | 74 (26.2) | 41 (29.1) | 33 (23.4) | ||
| 4 | 3 (1.1) | 2 (1.4) | 1 (0.7) | ||
| ypN, n (%) | 0.969 | Fisher | |||
| 1 | 188 (66.7) | 93 (66) | 95 (67.4) | ||
| 2 | 68 (24.1) | 34 (24.1) | 34 (24.1) | ||
| 3 | 24 (8.5) | 13 (9.2) | 11 (7.8) | ||
| 4 | 2 (0.7) | 1 (0.7) | 1 (0.7) | ||
| AJCC/TNM stage, n (%) | 0.236 | Fisher | |||
| 0 | 90 (31.9) | 37 (26.2) | 53 (37.6) | ||
| I | 63 (22.3) | 36 (25.5) | 27 (19.1) | ||
| II | 34 (12.1) | 19 (13.5) | 15 (10.6) | ||
| III | 91 (32.3) | 46 (32.6) | 45 (31.9) | ||
| IV | 4 (1.4) | 3 (2.1) | 1 (0.7) | ||
| pCR, n (%) | 0.041 | 4.178 | |||
| Yes | 90 (31.9) | 37 (26.2) | 53 (37.6) | ||
| No | 192 (68.1) | 104 (73.8) | 88 (62.4) | ||
| PT–TRG, n (%) | 0.135 | 5.558 | |||
| 0 | 112 (39.7) | 48 (34) | 64 (45.4) | ||
| 1 | 67 (23.8) | 33 (23.4) | 34 (24.1) | ||
| 2 | 83 (29.4) | 47 (33.3) | 36 (25.5) | ||
| 3 | 20 (7.1) | 13 (9.2) | 7 (5) | ||
| LN–TRG, n (%) | 0.996 | 0.181 | |||
| 0 | 170 (60.3) | 85 (60.3) | 85 (60.3) | ||
| 1 | 20 (7.1) | 10 (7.1) | 10 (7.1) | ||
| 2 | 17 (6.0) | 9 (6.4) | 8 (5.7) | ||
| 3 | 21 (7.4) | 11 (7.8) | 10 (7.1) | ||
| 4 | 54 (19.1) | 26 (18.4) | 28 (19.9) | ||
| Total carcinoma diameter (lymph node), mean ± SD | 0.2 ± 0.4 | 0.2 ± 0.4 | 0.2 ± 0.3 | 0.432 | 0.619 |
| Number of lymph nodes dissected | 18.6 ± 8.3 | 17.6 ± 7.2 | 19.5 ± 9.2 | 0.055 | 3.703 |
| WBC grade, n (%) | 0.438 | 0.602 | |||
| 0–2 | 196 (69.5) | 101 (71.6) | 95 (67.4) | ||
| 3–4 | 86 (30.5) | 40 (28.4) | 46 (32.6) | ||
| Hb grade, n (%) | 0.247 | Fisher | |||
| 0–2 | 279 (98.9) | 141 (100) | 138 (97.9) | ||
| 3–4 | 3 (1.1) | 0 (0) | 3 (2.1) | ||
| Platelet grade, n (%) | 0.622 | Fisher | |||
| 0–2 | 278 (98.6) | 138 (97.9) | 140 (99.3) | ||
| 3–4 | 4 (1.4) | 3 (2.1) | 1 (0.7) | ||
| Neutrophil grade, n (%) | 0.275 | 1.194 | |||
| 0–2 | 210 (74.5) | 109 (77.3) | 101 (71.6) | ||
| 3–4 | 72 (25.5) | 32 (22.7) | 40 (28.4) | ||
| Myelosuppression grade, n (%) | 0.254 | 1.3 | |||
| 0–2 | 189 (67.0) | 99 (70.2) | 90 (63.8) | ||
| 3–4 | 93 (33.0) | 42 (29.8) | 51 (36.2) |
Bold indicates that the difference is statistically significant