Table 1.
The clinicopathologic characteristics between the laparoscopic group and open group.
| Variables | Before PSM | P value | After PSM | P value | ||
|---|---|---|---|---|---|---|
| Laparoscopic group (n = 373) |
Open group (n = 542) |
Laparoscopic group (n = 318) |
Open group (n = 318) |
|||
| Propensity scores | ||||||
| 0.5 ± 0.1 | 0.3 ± 0.2 | < 0.001 | 0.5 ± 0.2 | 0.5 ± 0.2 | 0.056 | |
| Age, years (mean ± SD) | ||||||
| 57.1 ± 11.4 | 60.0 ± 12.0 | 0.019 | 57.4 ± 11.3 | 58.4 ± 11.3 | 0.245 | |
| Sex | ||||||
| Male | 175 (46.9) | 272 (50.2) | 0.346 | 148 (46.5) | 150 (47.2) | 0.937 |
| Female | 198 (53.1) | 270 (49.8) | 170 (53.5) | 168 (52.8) | ||
| BMI, kg/m2 (mean ± SD) | ||||||
| 24.3 ± 3.1 | 24.0 ± 3.1 | 0.179 | 24.2 ± 3.0 | 24.2 ± 3.1 | 0.859 | |
| Underlying disease | ||||||
| Hypertension | 98 (26.4) | 170 (31.2) | 0.121 | 84 (26.4) | 103 (32.4) | 0.117 |
| Cardiovascular | 17 (4.6) | 23 (4.2) | 0.870 | 13 (4.1) | 15 (4.7) | 0.847 |
| Cerebrovascular | 3 (0.8) | 3 (0.6) | 0.691 | 2 (0.6) | 1 (0.3) | 0.563 |
| Pulmonary disease | 19 (5.1) | 26 (4.8) | 0.877 | 15 (4.7) | 19 (6.0) | 0.598 |
| Hepatic disease | 22 (5.9) | 25 (4.6) | 0.366 | 27 (8.5) | 36 (11.3) | 0.288 |
| Diabetes mellitus | 30 (8.1) | 64 (11.8) | 0.077 | 19 (6.0) | 17 (5.3) | 0.864 |
| Renal disease | 2 (0.5) | 1 (0.2) | 0.569 | 2 (0.6) | 1 (0.3) | 0.563 |
| Radicality of resection | ||||||
| R0 resection | 368 (98.7) | 533 (98.3) | 0.790 | 313 (98.4) | 313 (98.4) | 1.000 |
| R1 resection | 5 (1.3) | 9 (1.7) | 5 (1.6) | 5 (1.6) | ||
| Extent of resection | ||||||
| Wedge resection | 343 (92.0) | 370 (68.3) | < 0.001 | 291 (91.5) | 288 (90.6) | 0.950 |
| Partial gastrectomy | 21 (5.6) | 88 (16.2) | 21 (6.6) | 22 (6.9) | ||
| Total gastrectomy | 2 (0.5) | 78 (14.4) | 2 (0.6) | 3 (0.9) | ||
| Enucleation | 7 (1.9) | 6 (1.1) | 4 (1.3) | 5 (1.6) | ||
| Combined resection | ||||||
| Total | 29 (7.8) | 83 (15.3) | < 0.001 | 27 (8.5) | 20 (6.3) | 0.363 |
| Cholecystectomy | 23 (6.2) | 19 (3.5) | 21 (6.6) | 12 (3.8) | ||
| Liver resection | 2 (0.5) | 5 (0.9) | 2 (0.5) | 1 (0.3) | ||
| Colon resection | 1 (0.3) | 17 (3.1) | 1 (0.3) | 2 (0.5) | ||
| Adrenalectomy | 1 (0.3) | 7 (1.3) | 1 (0.3) | 1 (0.3) | ||
| SB resection | 1 (0.3) | 3 (0.6) | 1 (0.3) | 1 (0.3) | ||
| Splenectomy | 0 (0) | 40 (7.4) | 0 (0) | 1 (0.3) | ||
| Pancreatectomy | 0 (0) | 20 (3.7) | 0 (0) | 1 (0.3) | ||
| Others | 3 (0.8) | 1 (0.3) | 3 (0.8) | 1 (0.3) | ||
| Tumor size, mean (mm) | ||||||
| 37.3 ± 18.6 | 65.2 ± 46.5 | < 0.001 | 38.3 ± 19.5 | 40.1 ± 17.0 | 0.217 | |
| Tumor size category (cm) | ||||||
| > 0, ≤ 2 | 62 (16.6) | 42 (7.7) | < 0.001 | 52 (16.4) | 38 (11.9) | 0.554 |
| > 2, ≤ 5 | 247 (66.2) | 241 (44.5) | 202 (63.5) | 206 (64.8) | ||
| > 5, ≤ 7 | 49 (13.1) | 96 (17.7) | 49 (15.4) | 58 (18.2) | ||
| > 7, ≤ 10 | 10 (2.7) | 67 (12.4) | 10 (3.1) | 11 (3.5) | ||
| > 10, ≤ 15 | 5 (1.3) | 69 (12.7) | 5 (1.6) | 5 (1.6) | ||
| > 15, ≤ 20 | 0 (0) | 17 (3.1) | 0 (0) | 0 (0) | ||
| > 20, ≤ 30 | 0 (0) | 9 (1.7) | 0 (0) | 0 (0) | ||
| > 30 | 0 (0) | 1 (0.2) | 0 (0) | 0 (0) | ||
| Longitudinal location | ||||||
| GEJ to Cardia | 59 (15.8) | 81 (14.9) | 0.540 | 53 (16.7) | 40 (12.6) | 0.417 |
| Upper third | 153 (41.0) | 234 (43.2) | 129 (40.6) | 146 (45.9) | ||
| Upper to middle | 1 (0.3) | 2 (0.4) | 1 (0.3) | 0 (0) | ||
| Middle third | 67 (18.0) | 96 (17.7) | 57 (17.9) | 47 (14.8) | ||
| Middle to lower | 0 (0) | 5 (0.9) | 1 (0.3) | 1 (0.3) | ||
| Lower third | 93 (24.9) | 123 (22.7) | 77 (24.2) | 83 (26.1) | ||
| Entire length | 0 (0) | 1 (0.2) | 0 (0) | 1 (0.3) | ||
| Circumferential location | ||||||
| Greater | 110 (29.5) | 141 (26.0) | 0.001 | 96 (30.2) | 89 (28.0) | 0.231 |
| Lesser | 80 (21.4) | 139 (25.6) | 68 (21.4) | 78 (24.5) | ||
| Anterior | 93 (24.9) | 90 (16.6) | 74 (23.3) | 58 (18.2) | ||
| Posterior | 90 (24.1) | 163 (30.1) | 80 (25.2) | 91 (28.6) | ||
| Entire | 0 (0) | 9 (1.7) | 0 (0) | 2 (0.6) | ||
| Locational preference | ||||||
| Favorable | 176 (47.2) | 203 (37.5) | 0.004 | 145 (45.6) | 130 (40.9) | 0.262 |
| Unfavorable | 197 (52.8) | 339 (62.5) | 173 (54.4) | 188 (59.1) | ||
| Mitotic rate (per 50 HPF) | ||||||
| ≤ 5 | 276 (74.0) | 352 (64.9) | < 0.001 | 242 (76.1) | 242 (76.1) | 0.225 |
| > 5, ≤ 10 | 71 (19.0) | 96 (17.7) | 56 (17.6) | 46 (14.5) | ||
| > 10 | 26 (7.0) | 94 (17.3) | 20 (6.3) | 30 (9.4) | ||
| NIH risk stratification | ||||||
| Very low | 49 (13.1) | 36 (6.6) | < 0.001 | 41 (12.9) | 32 (10.1) | 0.232 |
| Low | 183 (49.1) | 183 (33.8) | 157 (49.4) | 160 (50.3) | ||
| Intermediate | 100 (26.8) | 128 (23.6) | 85 (26.7) | 76 (23.9) | ||
| High | 41 (11.0) | 195 (36.0) | 35 (11.0) | 50 (15.7) | ||
| CD 117 | ||||||
| Yes | 306 (97.1) | 366 (98.4) | 0.303 | 260 (96.7) | 202 (99.0) | 0.125 |
| No | 9 (2.9) | 6 (1.6) | 9 (3.3) | 2 (1.0) | ||
| Unidentified | 58 cases | 170 cases | 49 case | 114 case | ||
| CD 34 | ||||||
| Yes | 281 (98.6) | 333 (97.9) | 0.762 | 241 (98.8) | 186 (98.4) | 0.752 |
| No | 4 (1.4) | 7 (2.1) | 3 (1.2) | 3 (1.6) | ||
| Unidentified | 88 case | 202 case | 74 case | 129 case | ||
| Adjuvant treatment (Gleevec) | ||||||
| Yes | 7 (1.9) | 52 (9.6) | < 0.001 | 7 (2.2) | 7 (2.2) | 1.000 |
| No | 366 (98.1) | 490 (90.4) | 311 (97.8) | 311 (97.8) | ||
GEJ gastroesophageal junction, HPF high power field, PSM propensity score matching, SD standard deviation, SB small bowel.