From: Second primary colorectal cancer in adults: a SEER analysis of incidence and outcomes
 | ipCRC | spCRC | ||||||
---|---|---|---|---|---|---|---|---|
Model 1 | Model 2 | Model 1 | Model 2 | |||||
HR | P | HR | P | HR | P | HR | P | |
Age | 1.04 (1.04–1.04) |  < 0.001 | 1.04 (1.04–1.04) |  < 0.001 | 1.02 (1.01–1.02) |  < 0.001 | 1.02 (1.02–1.03) |  < 0.001 |
Gender | ||||||||
 Female | Ref |  | Ref |  | Ref |  | Ref |  |
 Male | 1.00 (0.99–1.01) | 0.999 | 0.88 (0.87–0.89) |  < 0.001 | 1.05 (0.97–1.14) | 0.236 | 1.13 (1.04–1.23) | 0.003 |
Race | ||||||||
 White (ref) | Ref |  | Ref |  | Ref |  | Ref |  |
 black | 1.10 (1.09–1.12) |  < 0.001 | 1.15 (1.13–1.17) |  < 0.001 | 1.14 (1.01–1.29) | 0.031 | 1.20 (1.06–1.35) | 0.004 |
 Other | 0.83 (0.81–0.84) |  < 0.001 | 0.86 (0.84–0.87) |  < 0.001 | - | - |  |  |
 Unknown | 0.13 (0.11–0.15) |  < 0.001 | 0.18 (0.15–0.21) |  < 0.001 | 0.86 (0.74–0.99) | 0.033 | 0.89 (0.77–1.02) | 0.100 |
Insurance | ||||||||
 Insured | Ref |  | Ref |  | Ref |  | Ref |  |
 Uninsured | 1.56 (1.54–1.59) |  < 0.001 | 1.45 (1.42–1.47) |  < 0.001 | 1.02 (0.77–1.36) |  < 0.001 | 1.36 (1.16–1.59) | 0.001 |
 Insured/No specifics | 1.16 (1.14–1.17) |  < 0.001 | 1.13 (1.11–1.14) |  < 0.001 | 1.10 (0.96–1.27) | 0.1726 | 0.76 (0.69–0.83) |  < 0.001 |
 Any Medicaid | 1.30 (1.28–1.32) |  < 0.001 | 1.10 (1.08–1.12) |  < 0.001 | 1.35 (1.19–1.57) | 0.001 | 1.09 (0.94–1.25) | 0.250 |
 Unknown | 1.28 (1.24–1.33) |  < 0.001 | 1.45 (1.40–1.51) |  < 0.001 | 0.73 (0.66–0.80) | 0.730 | 1.22 (0.92–1.63) | 0.167 |
Site | ||||||||
 Right colon | Ref |  | Ref |  | Ref |  | Ref |  |
 Left colon | 0.79 (0.78–0.80) |  < 0.001 | 0.94 (0.93–0.95) |  < 0.001 | 0.77 (0.67–0.89) |  < 0.001 | 0.87 (0.74–1.02) | 0.081 |
 Others | 2.81 (2.74–2.88) |  < 0.001 | 1.35 (1.31–1.38) |  < 0.001 | 0.89 (0.78–1.03) | 0.113 | 1.12 (0.95–1.33) | 0.184 |
 Rectum | 0.78 (0.77–0.79) |  < 0.001 | 0.88 (0.86–0.89) |  < 0.001 | 0.93 (0.61–1.41) | 0.734 | 1.61 (0.86–3.01) | 0.134 |
Histology | ||||||||
 Adenocarcinoma | Ref |  | Ref |  | Ref |  | Ref |  |
 Mucous adenocarcinoma | 1.14 (1.12–1.16) |  < 0.001 | 1.06 (1.04–1.08) |  < 0.001 | 0.91 (0.79–1.06) | 0.226 | 0.88 (0.75–1.02) | 0.084 |
 Signet ring cell carcinoma | 2.22 (2.13–2.32) |  < 0.001 | 1.40 (1.34–1.46) |  < 0.001 | 1.64 (1.20–2.24) | 0.002 | 1.64 (1.19–2.25) | 0.002 |
 Others | 0.71 (0.70–0.72) |  < 0.001 | 0.85 (0.83–0.86) |  < 0.001 | 0.80 (0.72–0.88) |  < 0.001 | 0.93 (0.82–1.06) | 0.259 |
Grade | ||||||||
 Grade I/Grade II | Ref |  | Ref |  | Ref |  | Ref |  |
 Grade III/Grade IV | 1.48 (1.45–1.51) |  < 0.001 | 1.15 (1.11–1.18) |  < 0.001 | 1.20 (1.08–1.33) |  < 0.001 | 0.99 (0.89–1.11) | 0.947 |
 Unknown | 2.01 (1.96–2.06) |  < 0.001 | 1.27 (1.22–1.30) |  < 0.001 | 0.95 (0.84–1.07) | 0.367 | 1.05 (0.91–1.22) | 0.507 |
T stage | ||||||||
 T1/T2 | Ref |  | Ref |  | Ref |  | Ref |  |
 T3 | 1.52 (1.50–1.55) |  < 0.001 | 1.17 (1.14–1.20) |  < 0.001 | 1.46 (1.33–1.61) |  < 0.001 | 1.12 (0.93–1.37) | 0.224 |
 T4 | 3.25 (3.19–3.30) |  < 0.001 | 1.76 (1.71–1.80) |  < 0.001 | 2.23 (1.96–2.54) |  < 0.001 | 1.63 (1.32–2.01) |  < 0.001 |
 Unknown | 0.69 (0.66–0.72) |  < 0.001 | 1.17 (1.14–1.20) |  < 0.001 | 1.25 (1.09–1.44) | 0.001 | 1.19 (0.85–1.67) | 0.030 |
N stage | ||||||||
 N0 | Ref |  | Ref |  | Ref |  | Ref |  |
 N1 | 1.52 (1.50–1.54) |  < 0.001 | 1.18 (1.15–1.21) |  < 0.001 | 1.45 (1.31–1.61) |  < 0.001 | 1.06 (0.85–1.32) | 0.586 |
 N2 | 2.45 (2.42–2.49) |  < 0.001 | 1.80 (1.76–1.84) |  < 0.001 | 1.91 (1.70–2.15) |  < 0.001 | 1.36 (1.08–1.72) | 0.010 |
 N3 | - | - | - | - | 1.85 (0.69–4.94) | 0.219 | - | - |
 NX | 1.81 (1.78–1.84) |  < 0.001 | 1.05 (1.02–1.08) |  < 0.001 | 1.07 (0.92–1.24) | 0.382 | 1.86 (0.66–5.22) | 0.241 |
M stage | ||||||||
 M0 | Ref |  | Ref |  | Ref |  | Ref |  |
 M1 | 5.54 (5.48–5.61) |  < 0.001 | 3.00 (2.61–3.45) |  < 0.001 | 2.44 (2.13–2.78) |  < 0.001 | 4.51 (2.00–10.18) | 0.001 |
 MX | 1.23 (1.21–1.26) |  < 0.001 | 0.76 (0.73–0.79) |  < 0.001 | 0.85 (0.73–0.99) | 0.044 | 0.75 (0.52–1.08) | 0.120 |
AJCC | ||||||||
 0 | Ref |  | Ref |  |  |  |  |  |
 I | 1.20 (1.16–1.25) |  < 0.001 | 1.14 (1.10–1.19) |  < 0.001 | Ref | - | Ref |  |
 II | 1.68 (1.62–1.75) |  < 0.001 | 1.24 (1.18–1.30) |  < 0.001 | 1.39 (1.24–1.55) |  < 0.001 | 1.15 (0.93–1.43) | 0.188 |
 III | 2.18 (2.09–2.27) |  < 0.001 | 1.55 (1.48–1.63) |  < 0.001 | 1.85 (1.65–2.07) |  < 0.001 | 1.47 (1.08–1.98) | 0.013 |
 IV | 9.31 (8.95–9.68) |  < 0.001 | 1.84 (1.59–2.13) |  < 0.001 | 3.08 (2.65–3.58) |  < 0.001 | 0.61 (0.27–1.36) | 0.227 |
 Unknown stage | 2.47 (2.37–2.57) |  < 0.001 | 1.84 (1.74–1.94) |  < 0.001 | 1.23 (1.06–1.43) | 0.006 | 1.14 (0.79–1.63) | 0.483 |
 Radiation (No/Unknown) | 1.06 (1.05–1.08) |  < 0.001 | 1.04 (1.01–1.07) |  < 0.001 | 1.23 (1.10–1.38) |  < 0.001 | 1.82 (1.43–2.33) |  < 0.001 |
 Chemotherapy | 0.85 (0.84–0.86) |  < 0.001 | 1.47 (1.45–1.49) |  < 0.001 | 1.29 (1.19–1.40) |  < 0.001 | 0.94 (0.84–1.04) |  < 0.001 |
Radiation sequence | ||||||||
 Only one | Ref |  | Ref |  | Ref |  | Ref |  |
 After surgery | 0.90 (0.88–0.93) |  < 0.001 | 1.39 (1.33–1.44) |  < 0.001 | 1.24 (1.06–1.46) | 0.007 | 0.68 (0.47–0.81) | 0.001 |
 Before surgery | 0.60 (0.58–0.61) |  < 0.001 | 1.35 (1.31–1.40) |  < 0.001 | 0.95 (0.77–1.16) | 0.597 | 0.55 (0.40–0.74) |  < 0.001 |
 Both | 0.77 (0.56–1.08) | 0.128 | 1.17 (0.84–1.64) | 0.347 | 0.44 (0.11–1.76) | 0.246 | 0.37 (0.09–1.49) | 0.160 |
 Unknown | 1.79 (1.55–2.05) |  < 0.001 | 1.39 (1.20–1.60) |  < 0.001 | 0.39 (0.06–2.78) | 0.349 | 0.39 (0.05–2.80) | 0.350 |