Risk factors and a predictive nomogram for lymph node metastasis in superficial esophageal squamous cell carcinoma

Table 1 Patient clinicopathologic characteristics

Characteristics	No. of patients, n (%)
Gender
Male	367 (77.4)
Female	107 (22.6)
Age (yr), median (range)	60 (38-84)
Tumor size (mm), median (range)	23 (3-73)
Tumor location
Upper third	28 (5.9)
Middle third	303 (63.9)
Lower third	143 (30.2)
Paris classification
0-I	95 (20.0)
0-II	309 (65.2)
0-III	70 (14.8)
Depth of invasion
MM	152 (32.1)
SM1	80 (16.9)
SM2	106 (22.3)
SM3	136 (28.7)
Differentiation
Well	103 (21.7)
Moderate	279 (58.9)
Poor	92 (19.4)
INF pattern
INF-a	196 (41.4)
INF-b	232 (48.9)
INF-c	46 (9.7)
Tumor budding	64 (13.5)
LVI	27 (5.7)
LNM
Yes	90 (19.0)
No	384 (81.0)
Dissected LN, median (range)	18.0 (12-53)

MM: Muscularis mucosae; SM1: Upper third of submucosa; SM2: Middle third of submucosa; SM3: Lower third of submucosa; INF pattern: Infiltrative growth pattern; LVI: Lymphovascular invasion; LNM: Lymph node metastasis; LN: Lymph node.