Table 3.
Subset survival analysis of tumor-related factors for patients who did not and did receive postoperative chemotherapy
| Characteristic | No postoperative chemotherapy | Postoperative chemotherapy | p value |
|---|---|---|---|
| Median OS Months (95% CI) | |||
| Tumor differentiation | |||
| Well-/moderately differentiated | 111.54 (50.491–172.590) | NR | 0.850 |
| Poorly/undifferentiated | 41.20 (34.978–47.422) | 45.86 (37.871–53.849) | 0.220 |
| Lymphovascular invasion | |||
| Absent | NR | NR | 0.156 |
| Present | 32.72 (26.910–38.530) | 30.62 (24.525–36.715) | 0.969 |
| T class | |||
| T1 | NR | NR | 0.502 |
| T2 | NR | NR | 0.524 |
| T3 | 45.14 (33.465–56.815) | 54.08 (43.188–64.972) | 0.061 |
| T4 | 29.80 (24.257–35.343) | 32.16 (27.608–36.712) | 0.540 |
| N class | |||
| N0 | 111.54 (73.08–149.995) | NR | 0.415 |
| N1 | 41.30 (35.238–47.362) | 79.57 (50.900–108.240) | 0.025 |
| N2 | 31.24 (24.171–38.309) | 31.41 (26.274–36.546) | 0.594 |
| N3a | 25.66 (22.751–28.569) | 21.68 (16.001–27.359) | 0.608 |
| N3b | 16.76 (14.623–18.897) | 19.78 (14.529–25.031) | 0.574 |
| AJCC stage (ypTNM)a | |||
| I | NR | NR | 0.661 |
| II | NR | 85.16 (66.113–104.207) | 0.218 |
| III | 26.32 (23.382–29.258) | 29.63 (25.552–29.708) | 0.194 |
| Resection margin | |||
| R0 | 57.76 (46.778–68.742) | 70.11 (55.230–84.990) | 0.096 |
| R1 | 19.65 (13.180–26.120) | 20.57 (13.001–28.139) | 0.962 |
| Lymph nodes examined | |||
| < 15 | 49.91 (41.457–58.363) | 60.78 (n/a) | 0.057 |
| ≥ 15 | 55.23 (44.726–65.734) | 56.15 (41.312–70.988) | 0.569 |
OS overall survival, CI confidence interval, NR not reached, AJCC American Joint Committee on Cancer
aPatients labeled as T4 with no subclassification or NX were excluded