Table 1 Clinical and pathological characteristics of patients with solitary vs. synchronous CRC
From: Clinical characteristics of synchronous colorectal cancers in Japan
| Â | Solitary CRC | Synchronous CRC | P value* |
|---|---|---|---|
(921 cases; 93.6Â %) | (84 cases; 8.4Â %) | ||
Gender (male/female), no. | 575/346 | 62/22 | 0.044 |
Mean age, years ± SD | 67.1 ± 11.3 | 70.3 ± 9.5 | 0.028†|
Follow-up months ± SD | 44.6 ± 19.5 | 41.6 ± 18.7 | 0.097†|
Location of solitary |  |  | 0.031‡ |
 Right side | 308 (33.4 %) | 26 (31.0 %) |  |
 Left side | 282 (30.6 %) | 37 (44.0 %) |  |
 Rectum | 331 (35.9 %) | 21 (25.0 %) |  |
Average size; mm ± SD | 44.4 ± 25.6 | 43.8 ± 19.0 | 0.55†|
T factor |  |  | 0.26†|
 Tis | 32 (3.5 %) | 0 |  |
 T1 | 94 (10.2 %) | 7 (8.3 %) |  |
 T2 | 136 (14.8 %) | 12 (14.3 %) |  |
 T3 | 443 (48.1 %) | 49 (58.3 %) |  |
 T4 | 213 (23.1 %) | 16 (19 %) |  |
 No residual/uncertain§ | 3 (0.3 %) | 0 |  |
Differentiation | Â | Â | 0.25 |
 pap + wel + mod | 883 (95.9 %) | 83 (98.8 %) |  |
 poor + muc + sig | 38 (4.1 %) | 1 (1.2 %) |  |
Lymph node metastasis | Â | Â | 0.81 |
 N0 | 573 (62.2 %) | 51 (60.7 %) |  |
 N1/2/3/4 | 348 (37.8 %) | 33 (39.3 %) |  |
Stage, no. | Â | Â | 0.45 |
 0 | 32 (3.2 %) | 0 |  |
 I | 185 (18.4) | 15 (17.9 %) |  |
 II | 322 (35.0 %) | 31 (36.9 %) |  |
 III | 270 (29.3 %) | 26 (31.0 %) |  |
 IV | 112 (12.2 %) | 12 (14.3 %) |  |
Survival ratio | Â | Â | 0.62|| |
 3 years | 83.1 % | 81.0 % |  |
 5 years | 75.7 % | 74.5 % |  |
Extracolonic malignancies | Â | Â | 0.85 |
 No | 828 (89.9 %) | 75 (89.3 %) |  |
 Yes | 93 (10.1 %) | 9 (10.7 %) |  |