Table 2.
Baseline characteristics according to Siewert classification (N = 395)
| Clinicopathological features | Total No. | Tumor location by Siewert classification | P (across 3 Siewert types) | ||
|---|---|---|---|---|---|
| Type I (N = 59) | Type II (N = 280) | Type III (N = 56) | |||
| Sex | |||||
| Female | 63 (16%) | 5 (9%) | 46 (16%) | 12 (21%) | .15 |
| Male | 332 (84%) | 54 (91%) | 234 (84%) | 44 (79%) | |
| Age at surgery (y, mean ± SD) | 65.0 ± 12.3 | 63.1 ± 11.5 | 64.7 ± 12.6 | 68.5 ± 11.3 | .060 |
| Year since surgery | |||||
| Before Dec. 2009 | 181 (46%) | 15 (25%) | 128 (46%) | 38 (68%) | <.0001 |
| Jan. 2010 to Mar. 2015 | 214 (54%) | 44 (75%) | 152 (54%) | 18 (32%) | |
| Body mass index (kg/m2, mean ± SD) | 22.7 ± 3.4 | 23.1 ± 4.3 | 22.8 ± 3.2 | 22.1 ± 3.4 | .28 |
| <22.6 (median) | 195 (50%) | 25 (43%) | 138 (50%) | 32 (57%) | .33 |
| ≥22.6 (median) | 196 (50%) | 33 (57%) | 139 (50%) | 24 (43%) | |
| Tumor diameter (mm, mean ± SD) | 54.9 ± 30.7 | 45.1 ± 28.0
|
51.4 ± 28.1
|
82.5 ± 31.1 | <.0001 |
| <50 (median) | 185 (47%) | 39 (66%) | 139 (50%) | 7 (13%) | <.0001 |
| ≥50 (median) | 210 (53%) | 20 (34%) | 141 (50%) | 49 (87%) | |
| Barrett's esophagus | |||||
| Absent | 271 (69%) | 13 (22%) | 204 (73%) | 54 (96%) | <.0001 |
| Present | 124 (31%) | 46 (78%) | 76 (27%) | 2 (4%) | |
| Helicobacter pylori infection (Limited to Cancer Institute Hospital cases) | |||||
| Negative | 100 (44%) | 35 (79%) | 64 (39%) | 1 (5%) | <.0001 |
| Positive | 128 (56%) | 9 (21%) | 100 (61%) | 19 (95%) | |
| pT Stage | |||||
| pT1 | 101 (26%) | 27 (46%) | 71 (25%) | 3 (5%) | <.0001 |
| pT2 | 54 (14%) | 6 (10%) | 47 (17%) | 1 (2%) | |
| pT3 | 137 (34%) | 23 (39%) | 95 (34%) | 19 (34%) | |
| pT4 | 103 (26%) | 3 (5%) | 67 (24%) | 33 (59%) | |
| pN Stage | |||||
| pN0 | 157 (39%) | 28 (47%) | 117 (41%) | 12 (21%) | .021 |
| pN1 | 79 (20%) | 10 (17%) | 58 (21%) | 11 (20%) | |
| pN2 | 65 (17%) | 8 (14%) | 47 (17%) | 10 (18%) | |
| pN3 | 94 (24%) | 13 (22%) | 58 (21%) | 23 (41%) | |
| No. of nodes harvested (mean ± SD) | 34.9 ± 17.8 | 37.3 ± 19.8 | 33.3 ± 16.1
|
40.6 ± 22.0 | .020 |
| No. of metastatic nodes (mean ± SD) | 4.2 ± 6.7 | 3.5 ± 5.3
|
3.7 ± 5.9
|
7.7 ± 9.9 | .0010 |
| M stage | |||||
| M0 | 336 (85%) | 54 (91%) | 242 (86%) | 40 (71%) | .0051 |
| M1 | 59 (15%) | 5 (9%) | 38 (14%) | 16 (29%) | |
| pStage | |||||
| I | 115 (29%) | 25 (42%) | 87 (31%) | 3 (5%) | .0002 |
| II | 51 (13%) | 7 (12%) | 37 (13%) | 7 (13%) | |
| III | 170 (43%) | 22 (37%) | 118 (42%) | 30 (53%) | |
| IV | 59 (15%) | 5 (9%) | 38 (14%) | 16 (29%) | |
| Adjuvant chemotherapy | |||||
| Absent | 237 (61%) | 35 (59%) | 176 (63%) | 26 (48%) | .10 |
| Present | 153 (39%) | 24 (41%) | 101 (37%) | 28 (52%) | |
| Histological subtypes | |||||
| Lauren classification | |||||
| Intestinal | 305 (77%) | 49 (83%) | 217 (77%) | 39 (70%) | .23 |
| Diffuse | 90 (23%) | 10 (17%) | 63 (23%) | 17 (30%) | |
| WHO classification | |||||
| Papillary | 7 (2%) | 1 (2%) | 4 (1%) | 2 (4%) | .30 |
| Tubular | 280 (70%) | 47 (79%) | 200 (71%) | 33 (59%) | |
| Mucinous | 18 (5%) | 1 (2%) | 13 (5%) | 4 (7%) | |
| Poorly cohesive | 90 (23%) | 10 (17%) | 63 (23%) | 17 (30%) | |
| Lymphatic invasion | |||||
| Absent | 123 (32%) | 26 (44%) | 82 (30%) | 15 (27%) | .077 |
| Present | 265 (68%) | 33 (56%) | 191 (70%) | 41 (73%) | |
| Venous invasion | |||||
| Absent | 130 (33%) | 27 (46%) | 84 (30%) | 19 (34%) | .076 |
| Present | 261 (67%) | 32 (54%) | 192 (70%) | 37 (66%) | |
| Surgical approach | |||||
| Transhiatal | 313 (79%) | 13 (22%) | 244 (87%) | 56 (100%) | <.0001 |
| Transthoracic | 82 (21%) | 46 (78%) | 36 (13%) | 0 | |
| Operative time (min, mean ± SD) | 346 ± 141 |
493 ± 149
|
321 ± 123 | 318 ± 127 | <.0001 |
| <320 (median) | 194 (50%) | 5 (9%) | 158 (57%) | 31 (56%) | <.0001 |
| ≥320 (median) | 194 (50%) | 52 (91%) | 118 (43%) | 24 (44%) | |
| Blood loss volume (g, mean ± SD) | 461 ± 414 | 450 ± 400
|
432 ± 391
|
613 ± 502 | .0084 |
| <350 (median) | 188 (49%) | 28 (49%) | 139 (50%) | 21 (38%) | .25 |
| ≥350 (median) | 199 (51%) | 29 (51%) | 136 (50%) | 34 (62%) | |
| Blood transfusion | |||||
| Absent | 343 (88%) | 51 (89%) | 248 (90%) | 44 (79%) | .056 |
| Present | 46 (12%) | 6 (11%) | 28 (10%) | 12 (21%) | |
| Resection margin | |||||
| R0 | 346 (87%) | 57 (96%) | 248 (89%) | 41 (73%) | .0041 |
| R1 | 26 (7%) | 1 (2%) | 17 (6%) | 8 (14%) | |
| R2 | 23 (6%) | 1 (2%) | 15 (5%) | 7 (13%) | |
| Preoperative complications | |||||
| None or Clavien‐Dindo < IIIa | 315 (80%) | 41 (69%) | 227 (81%) | 47 (84%) | .093 |
| Clavien‐Dindo ≥ IIIa | 80 (20%) | 18 (31%) | 53 (19%) | 9 (16%) | |
(%) Indicates the proportion of cases with specific clinicopathological features for each Siewert classification group. * P < .05, **P < .01, ***P < .001.
Abbreviation: SD, standard deviation.