Lymph node ratio and preoperative CA 19-9 levels predict overall survival and recurrence-free survival in patients with resected pancreatic adenocarcinoma

Table 2 Clinicopathologic characteristics n (%)

Resection margin
Negative	122 (72.2)
Positive	47 (27.8)
Perineural invasion
Negative	41 (24.2)
Positive	127 (75.1)
Unknown	1 (0.6)
Peripancreatic extension
Negative	28 (16.6)
Positive	141 (83.4)
Unknown	1 (0.6)
TNM stage
I	16 (9.5)
IIA	39 (23.1)
IIB	98 (58.0)
III	10 (5.9)
IV	5 (3.0)
Unknown	1 (0.6)
Tumor grade
1	24 (14.2)
2	94 (55.6)
3	48 (28.4)
Unknown	4 (2.4)
LN examined (n = 167)2	11.0 (7.5-18)1
LN positive (n = 167)2	1.0 (0.0-4.0)1
LN examined (n = 150)3	12.0 (8.0-18.0)1
LN positive (n = 150)3	1.0 (0.0-4.0)1
LN ratio (n = 167)	0.09 (0.0-0.29)1
Tumor size (cm) (n = 167)	3.0 (2.1-3.6)1
CA 19-9 (U/mL) (n = 124)	146.0 (47.5-378.2)1

The total number of patients is 169.

¹Median (interquartile range);

²All procedures;

³Whipple procedures. TNM: Tumor-node-metastasis; LN: Lymph node; CA: Carbohydrate antigen.