Table 3.
Hazard ratio of metachronous colon cancer following segmental colon resection for first colon cancer
| Univariate | Multivariate^ | |||
|---|---|---|---|---|
| HR (95%CI) | P | HR (95%CI) | P | |
| Sex | ||||
| Male | 1.00 (Referent) | 1.00 (Referent) | ||
| Female | 1.08 (0.68–1.72) | 0.74 | 1.68 (0.75–3.75) | 0.21 |
| Age (years) | ||||
| < 40 | 1.00 (Referent) | 1.00 (Referent) | ||
| 40 – 49 | 1.40 (0.82–2.38) | 0.69† | 1.29 (0.49–3.41) | 0.43† |
| ≥50 | 1.09 (0.59–2.03) | 1.42 (0.60–3.35) | ||
| MMR gene mutated | ||||
| MLH1 | 1.00 (Referent) | 1.00 (Referent) | ||
| MSH2 | 1.19 (0.75–1.90) | 0.46 | 1.21 (0.62–2.35) | 0.58 |
| MSH6 | 0.63 (0.21–2.24) | 0.53 | 0.84 (0.22–3.24) | 0.80 |
| PMS2 | - | - | ||
| Country of recruitment | ||||
| Australasia | 1.00 (Referent) | 1.00 (Referent) | ||
| Canada | 2.73 (1.57–4.75) | <0.001 | 5.00 (2.04–12.29) | <0.001 |
| USA | 1.40 (0.80–2.43) | 0.24 | 2.71 (1.21–6.06) | 0.02 |
| Length of bowel removed (per 10 cm) | 0.72 (0.56 – 0.93) | 0.01 | 0.69 (0.54–0.88) | 0.002 |
| Characteristics of first colon cancer | ||||
| Site of tumour in colon | ||||
| Right colon* | 1.00 (Referent) | 1.00 (Referent) | ||
| Left colon** | 1.46 (0.89–2.41) | 0.14 | 1.46 (0.61–3.50) | 0.40 |
| Rectosigmoid | 1.50 (0.47–4.86) | 0.50 | 2.02 (0.32–12.83) | 0.46 |
| Maximum dimension of tumour | ||||
| Tertile 1 (10 – 40 mm) | 1.00 (Referent) | 1.00 (Referent) | ||
| Tertile 2 (41 – 60 mm) | 0.75 (0.38 – 1.46) | 0.99† | 0.62 (0.24–1.64) | 0.59† |
| Tertile 3 (61 – 140 mm) | 1.00 (0.52 – 1.95) | 0.78 (0.32–1.90) | ||
| AJCC Stage of Tumor | ||||
| I | 1.00 (Referent) | 1.00 (Referent) | ||
| II (A, B, C) | 1.36 (0.68–2.70) | 0.08† | 0.94 (0.35–2.55) | 0.48† |
| III (A, B, C) | 1.91 (0.91–4.03) | 1.40 (0.51–3.87) | ||
| Histological grade | ||||
| Well | 1.00 (Referent) | 1.00 (Referent) | ||
| Moderate | 1.04 (0.46–2.36) | 1.92 (0.52–7.06) | ||
| Poor | 0.98 (0.40–2.40) | 0.75† | 1.89 (0.45–7.86) | 0.40† |
| Mucinous | 1.48 (0.43–5.11) | 2.83 (0.32–24.70) | ||
| Synchronous tumour | ||||
| Absent | 1.00 (Referent) | 1.00 (Referent) | ||
| Present | 1.56 (0.57–4.30) | 0.39 | 1.28 (0.40–4.07) | 0.67 |
†
P trend: calculated from Cox regression models with ordinal variables as continuous measures.
^
adjusted for variables in the table and height of individuals, with robust variance correction for familial correlation
*
Right colon included caecum, ascending colon, hepatic flexure and transverse colon
**
Left colon included descending colon and sigmoid colon