Table 2. Cox regression model for the independent prognostic significance of necrosis in the study cohort.
|
DFS |
CSS |
OS |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| HR | 95% CI | P-value | HR | 95% CI | P-value | HR | 95% CI | P-value | |
| Age (<65 vs ⩾65 years) | 3.69 | 1.25–10.9 | 0.018 | 2.34 | 1.00–5.45 | 0.049 | 2.39 | 1.18–4.81 | 0.015 |
| Tumour invasion (T1–T2 vs T3–T4) | 0.61 | 0.16–2.30 | 0.470 | 0.77 | 0.19–3.12 | 0.711 | 1.01 | 0.38–2.72 | 0.978 |
| Nodal metastases (N0 vs N1-N2) | 14.3 | 4.09–49.9 | 3.10E−5 | 3.97 | 1.45–10.9 | 7.3E−3 | 2.96 | 1.51–5.81 | 1.6E−3 |
| Distant metastases (M0 vs M1) | — | — | — | 5.65 | 2.18–14.7 | 3.9E−4 | 3.33 | 1.55–7.16 | 2.1E−3 |
| WHO Grade (1–2 vs 3) | — | — | — | — | — | — | — | — | — |
| Tumour location (Colon vs Rectum) | 1.00 | 0.34–2.89 | 0.992 | 1.84 | 0.73–4.61 | 0.193 | 1.14 | 0.56–2.34 | 0.714 |
| Preoperative RT/CRT (No vs Yes) | 0.66 | 0.19–2.34 | 0.525 | 0.25 | 0.05–1.16 | 0.077 | 0.49 | 0.17–1.40 | 0.185 |
| Serrated histology (No vs Yes) | — | — | — | — | — | — | — | — | — |
| Infiltrative tumour border (No vs Yes) | 4.35 | 1.56–12.2 | 5.1E−3 | — | — | — | — | — | — |
| Lymphatic or blood vessel invasion (No vs Yes) | — | — | — | 3.03 | 1.06–8.70 | 0.039 | — | — | — |
| Tumour necrosis (<10% vs ⩾10%) | 2.80 | 1.03–7.63 | 0.045 | 1.57 | 0.59–4.17 | 0.364 | 1.45 | 0.71–2.96 | 0.312 |
| CD105 MVD (<10 mm−2 vs ⩾10 mm−2) | 3.13 | 1.14–8.59 | 0.027 | — | — | — | — | — | — |
Abbreviations: CI=confidence interval; CSS=cancer-specific survival; DFS=disease-free survival; HR=hazard ratio; MVD=microvascular density; OS=overall survival; RT/CRT=radiotherapy/chemoradiotherapy; TNM=tumour, node and metastasis.
All the models included TNM stage variables, tumour location, preoperative RT/CRT, and tumour necrosis. Other variables were selected utilising the stepwise forward selection method based on their significance in the model.