Table 1: Clinical characteristics of two groups.

Group PGroup R value

Number of patients5039
Gender (male/female)37/1333/60.23
Mean age (years ± SD) 0.90
Location (U/M/L)3/10/3716/12/11<0.001
Gross type (elevated/others)15/3513/260.74
Mean maximum diameter of tumor (mm ± SD) 0.18
Mean maximum diameter of specimen (mm ± SD) 0.06
Tumor depth (mucosal cancer/submucosal cancer)47/328/110.004

SD: standard deviation.