Table 1 Clinicopathological characteristics of the training (n = 71) and validation cohorts (n = 75)
Clinicopathologic indexes | Training cohort (n = 71) | Validation cohort (n = 75) | P |
|---|---|---|---|
Age (mean, y ± SD) | 54 ± 12 | 54 ± 12 | 0.801 |
Gender | 0.011 | ||
Male | 47 (66%) | 34 (45%) | |
Female | 24 (34%) | 41 (55%) | |
Tumor differentiation | 0.005 | ||
Well/Moderately | 34 (48%) | 56 (75%) | |
Poorly/Undifferentiated | 37 (52%) | 19 (25%) | |
Distance from anal verge | 0.259 | ||
≦5 cm | 35 (49%) | 30 (40%) | |
> 5 cm | 36 (51%) | 45 (60%) | |
Tumor length (median; range) | 4 (2–12) | 4 (2–11) | 0.948 |
Circumferential extent | 0.113 | ||
≦50% | 17 (24%) | 27 (36%) | |
> 50% | 54 (76%) | 48 (64%) | |
Pretreatment T stage | < 0.001 | ||
T2 | 0 | 6 (8%) | |
T3 | 52 (73%) | 62 (83%) | |
T4 | 19 (27%) | 7 (9%) | |
Pretreatment N stage | 0.119 | ||
N0 | 12 (17%) | 21 (28%) | |
N1 | 30 (42%) | 34 (45%) | |
N2 | 29 (41%) | 20 (27%) | |
Pre- treatment CEA level (mean, ng/mL; rang) | 27 (5–200) | 14 (5–57) | 0.001 |
Post- treatment CEA level (mean, ng/mL; rang) | 5 (0.5–45) | 6 (0.5–34) | 0.605 |
Normalization of post- treatment CEA Level | 0.541 | ||
Normal (< 5 ng/mL) | 47 (66%) | 46 (61%) | |
Elevated (≧5 ng/mL) | 24 (34%) | 29 (39%) | |
CEA clearance pattern | 0.599 | ||
Exponential decrease (R2≧0.9) | 31 (44%) | 36 (48%) | |
Non-exponential decrease (R2 < 0.9) | 40 (56%) | 39 (52%) |