Table 3.
Postoperative outcomes stratified by the presence of oligometastases
| Variable | No oligometastases (n = 982) | Oligometastases (n = 27) | p value* |
|---|---|---|---|
| Preoperative chemotherapy | 52 (5.3) | 3 (11.1) | 0.178 |
| R1 margin | 119 (12.2) | 9 (34.6) | 0.003 |
| Lymph node metastases | 160 (16.3) | 15 (55.6) | < 0.001 |
| Multiple lesions | 178 (18.2) | 7 (25.9) | 0.314 |
| Direct invasion other organ | 64 (6.6) | 13 (48.1) | < 0.001 |
| Perineural invasion | 143 (16.2) | 5 (19.2) | 0.596 |
| Major vascular invasion | 95 (9.7) | 5 (18.5) | 0.179 |
| Major resection | 571 (58.4) | 20 (74.1) | 0.104 |
| Postoperative complication | 419 (42.7) | 19 (70.4) | 0.004 |
| Clavien–Dindo Grade | 0.691 | ||
| I-II | 241 (57.2) | 10 (52.6) | |
| IIIa-V | 180 (42.8) | 9 (47.4) | |
| 90-day postoperative mortality | 55 (5.6) | 6 (22.2) | 0.004 |
| Length of stay, days | 12 (7–17) | 13 (9–20) | 0.197 |
| Recurrence | 550 (56.0) | 17 (63.0) | 0.472 |
*Fisher’s exact test was used for categorical variables with expected counts < 5