Table 1. Characteristics of colon adenocarcinoma patients in the The Cancer Genome Atlas (TCGA) database.

Variable	TCGA (n=459)
Gender
Male	243
Female	216
Age at diagnosis
≤65 years	190
>65 years	269
Stage
I	76
II	178
III	129
IV	65
Unknown	11
T stage
Tis	1
T1	11
T2	78
T3	313
T4	56
N stage
N0	270
N1	106
N2	83
M stage
M0	337
M1	65
Unknown	57

Stage: a combination of T, N and M stages is used to determine colon cancer Stage; I: the cancer cells grow into the second or third layer of the colon wall, and there are no cancer cells in the nearby lymph nodes or the extracolonic area; II: the cancer cells have grown to or beyond the fourth layer of the colon wall, and there are no cancer cells in the nearby lymph nodes or outside the colon; III: the cancer has spread from the colon to nearby lymph nodes or there is tumor deposition. Tumor deposits are small tumors in the fat around the colon. IV: the cancer has spread beyond the colon and to nearby lymph nodes; Tis: carcinoma in situ; T1: tumor invasion into the submucosa; T2: the tumor invaded the muscularis propria of the intestinal wall; T3: the tumor penetrated into the muscularis propria and invaded subserosal layer, or when the primary lesion was located in the colon and rectum without serosal layer, the tumor had invaded paracolonic or rectal tissues; T4: the tumor has penetrated the peritoneum or directly invaded other organs; N0: no metastasis to regional lymph nodes; N1: 1–3 regional lymph node metastases; N2: ≥4 regional lymph node metastases; M0: no distant metastasis; M1: there are distant metastases.