Table 2. Risk of CRC recurrence during follow-up in relation to methylation status in patients with colorectal cancer after surgery.
| Recurrence in different stages by methylation | Normal tissues | Tumor tissues | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No. of subjects | Incidence rate | Crude | Adjusted | No. of subjects | Incidence rate | Crude | Adjusted | |||||||
| HR | 95% CI | HR | 95% CI | HR | 95% CI | HR | 95% CI | |||||||
| p16 | ||||||||||||||
| UnMe/local (1&2) a | 74 | (1767) | 4.53 | 1.00 | (Referent) | 1.00 | (Referent) | 51 | (1358) | 4.42 | 1.00 | (Referent) | 1.00 | (Referent) |
| UnMe/advanced (3&4) b | 78 | (1941) | 23.70 | 5.08 | (2.40–10.77) | 6.07 | (2.35–15.70) | 46 | (1180) | 21.19 | 4.69 | (1.89–11.65) | 6.63 | (1.97–22.38) |
| Me/local (1&2) c | 34 | (1032) | 3.88 | 0.70 | (0.18–2.62) | 0.98 | (0.23–4.17) | 57 | (1442) | 4.16 | 0.87 | (0.28–2.70) | 1.15 | (0.27–4.94) |
| Me/advanced (3&4) d | 29 | (621) | 43.48 | 9.92 | (4.47–21.99) | 10.85 | (4.06–28.96) | 61 | (1383) | 34.71 | 8.01 | (3.34–19.16) | 9.64 | (2.92–31.81) |
| MLH1 | ||||||||||||||
| UnMe/local (1&2) a | 92 | (2411) | 4.98 | 1.00 | (Referent) | 1.00 | (Referent) | 86 | (2148) | 5.12 | 1.00 | (Referent) | 1.00 | (Referent) |
| UnMe/advanced (3&4) b | 85 | (2098) | 25.74 | 5.28 | (2.76–10.11) | 5.79 | (2.67–12.57) | 80 | (1960) | 26.53 | 5.37 | (2.73–10.57) | 6.08 | (2.66–13.89) |
| Me/local (1&2) c | 16 | (389) | NA e | NA e | NA e | NA e | NA e | 22 | (652) | 1.53 | 0.30 | (0.04–2.32) | 0.48 | (0.06–3.90) |
| Me/advanced (3&4) d | 22 | (465) | 40.86 | 8.71 | (4.12–18.41) | 9.04 | (3.79–21.54) | 27 | (603) | 34.83 | 6.67 | (3.14–14.17) | 8.29 | (3.40–20.22) |
| MGMT | ||||||||||||||
| UnMe/local (1&2) a | 97 | (2625) | 4.19 | 1.00 | (Referent) | 1.00 | (Referent) | 52 | (1424) | 3.51 | 1.00 | (Referent) | 1.00 | (Referent) |
| UnMe/advanced (3&4) b | 87 | (2154) | 26.00 | 6.50 | (3.32–12.74) | 7.63 | (3.34–17.47) | 44 | (1166) | 24.87 | 6.61 | (2.52–17.37) | 7.61 | (2.23–25.91) |
| Me/local (1&2) c | 11 | (176) | 5.68 | 1.93 | (0.24–15.17) | 3.04 | (0.37–25.05) | 56 | (1376) | 5.09 | 1.32 | (0.42–4.15) | 1.48 | (0.35–6.25) |
| Me/advanced (3&4) d | 20 | (408) | 41.67 | 11.71 | (5.32–25.76) | 12.61 | (4.90–32.44) | 63 | (1396) | 31.52 | 9.41 | (3.66–24.17) | 11.83 | (3.49–40.12) |
HR, hazard ratio; CI, confidence interval; N/A, not available.
Adjusted for gender, age at surgery (continuous), and adjuvant chemotherapy.
a UnMe/loccal (1&2): gene promoter region unmethylation in cancer stage 1 or 2.
b UnMe/advanced (3&4): DNA promoter region unmethylation in cancer stage 3 or 4.
c Me/local (1&2): DNA promoter region methylation in cancer stage 1 or 2.
d Me/advanced (3&4): DNA promoter region methylation in cancer stage 3 or 4.
e Not available due to limited numbers of cases.