Table 3.
Univariate analysis of prognostic factors in subgrouping patients according to downstage and LNM after preoperative CRT
| Clinicopathological characteristic | Non-downstage group |
Downstage group |
non LNM group |
LNM group |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n (%) |
p-valuea) |
n (%) |
p-valuea) |
n (%) |
p-valuea) |
n (%) |
p-valuea) |
|||||
| RFS | CSS | RFS | CSS | RFS | CSS | RFS | CSS | |||||
| Pretreatment CEA (ng/mL)b) | ||||||||||||
| <5 | 30 (58.8) | 0.659 | 0.646 | 61 (71.3) | 0.282 | 0.095 | 67 (72.8) | 0.346 | 0.092 | 24 (54.5) | 0.541 | 0.454 |
| ≥5 | 21 (41.2) | 24 (28.2) | 25 (27.2) | 20 (45.5) | ||||||||
| Tumor distance from anal verge (cm) | ||||||||||||
| <5 | 40 (74.1) | 0.414 | 0.222 | 72 (78.3) | 0.736 | 0.9 | 78 (78.8) | 0.835 | 0.909 | 34 (72.3) | 0.347 | 0.185 |
| ≥5 | 14 (25.9) | 20 (21.7) | 21 (21.2) | 13 (27.7) | ||||||||
| Residual tumor size (cm) | ||||||||||||
| <6.0 | 23 (42.6) | 0.451 | 0.354 | 49 (53.3) | 0.024 | 0.008 | 52 (52.5) | 0.018 | 0.009 | 20 (42.6) | 0.566 | 0.331 |
| ≥6.0 | 31 (57.4) | 43 (46.7) | 47 (47.5) | 27 (57.4) | ||||||||
| ypT category | ||||||||||||
| T1 | 0 (0) | <0.001 | <0.001 | 4 (4.3) | 0.003 | 0.406 | 4 (4.0) | 0.004 | 0.414 | 0 (0) | <0.001 | <0.001 |
| T2 | 6 (11.1) | 27 (29.3) | 27 (27.3) | 6 (12.8) | ||||||||
| T3 | 41 (75.9) | 59 (64.1) | 66 (66.7) | 34 (72.3) | ||||||||
| T4 | 7 (10.0) | 2 (2.2) | 2 (2.0) | 7 (14.9) | ||||||||
| Tumor regression grade | ||||||||||||
| 0 | 2 (3.7) | <0.001 | <0.001 | 2 (2.2) | 0.845 | 0.397 | 2 (2.0) | 0.846 | 0.348 | 2 (4.3) | <0.001 | <0.001 |
| 1 | 8 (14.8) | 13 (14.1) | 13 (13.1) | 8 (17.0) | ||||||||
| 2 | 22 (40.7) | 33 (35.9) | 26 (36.4) | 19 (40.4) | ||||||||
| 3 | 22 (40.7) | 44 (47.8) | 48 (48.5) | 18 (38.3) | ||||||||
| Lymphatic invasion | ||||||||||||
| No | 25 (46.3) | 0.041 | 0.035 | 87 (94.6) | 0.924 | 0.287 | 94 (94.9) | 0.964 | 0.301 | 18 (38.3) | 0.12 | 0.144 |
| YES | 29 (53.7) | 5 (5.4) | 5 (5.1) | 29 (61.7) | ||||||||
| Perineural invasion | ||||||||||||
| No | 32 (59.3) | <0.001 | <0.001 | 80 (87.0) | 0.286 | 0.105 | 86 (86.9) | 0.409 | 0.136 | 26 (55.3) | <0.001 | <0.001 |
| YES | 22 (40.7) | 12 (13.0) | 13 (13.1) | 21 (44.7) | ||||||||
| Venous invasion | ||||||||||||
| No | 49 (90.7) | <0.001 | <0.001 | 92 (100) | NE | NE | 99 (100) | NE | NE | 42 (89.4) | <0.001 | <0.001 |
| YES | 5 (9.3) | 0 (0) | 0 (0) | 5 (10.6) | ||||||||
| Circumferential resection margin (mm) | ||||||||||||
| ≤1 | 44 (81.5) | <0.001 | <0.001 | 72 (78.3) | 0.002 | 0.002 | 78 (78.8) | <0.001 | 0.001 | 38 (80.9) | <0.001 | <0.001 |
| >1 | 10 (18.5) | 20 (21.7) | 21 (21.2) | 9 (19.1) | ||||||||
| KRAS mutationb) | ||||||||||||
| Negative | 29 (69.0) | 0.382 | 0.631 | 47 (74.6) | 0.1 | 0.085 | 48 (71.6) | 0.117 | 0.141 | 28 (73.7) | 0.204 | 0.191 |
| Positive | 13 (31.0) | 16 (25.4) | 19 (28.4) | 10 (26.3) | ||||||||
| BRAF mutationb) | ||||||||||||
| Negative | 39 (92.9) | 0.223 | 0.204 | 62 (67.4) | 0.483 | 0.672 | 66 (98.5) | 0.491 | 0.681 | 35 (92.1) | 0.277 | 0.278 |
| Positive | 3 (7.1) | 1 (1.1) | 1 (1.5) | 3 (7.9) | ||||||||
LNM, lymph node metastasis; CEA, carcinoembryonic antigen; CRT, chemoradiotherapy; RFS, recurrence free survival; CSS, cancer-specific survival, NE, not evaluated.
a)
p-values were calculated using log-rank test.
b)
Missing value is included.