Outcomes and prognostic factors of patients with stage IB and IIA pancreatic cancer according to the 8th edition American Joint Committee on Cancer criteria

Table 1 Clinical characteristics of the entire patient cohort¹n (%)

Characteristic	Entire cohort	Stage IB	Stage IIA	P value
Number of patients	1349	886	463
Age (yr), median (range)	65 (18-90)	65 (18-90)	63 (18-90)	0.000
Tumor size (mm), mean (range)	43.4 (21-540)	29.5 (21-40)	70.0 (41-540)	0.000
Gender
Male	626 (46.40)	405 (45.71)	221 (47.73)	0.480
Female	723 (53.60)	481 (54.29)	242 (52.27)
Primary site
Head	633 (46.9)	486 (54.85)	147 (31.75)	0.000
Body	165 (12.23)	103 (11.6)	62 (13.39)
Tail	350 (25.95)	186 (20.99)	164 (35.21)
Other	201 (14.90)	111 (12.53)	90 (19.44)
Grade
I	348 (25.80)	221 (24.94)	127 (27.43)	0.006
II	484 (35.88)	335 (37.81)	149 (32.18)
III	230 (17.05)	164 (18.52)	66 (14.25)
IV	17 (1.26)	10 (1.13)	7 (1.51)
Unknown	270 (20.01)	156 (17.61)	114 (24.62)
Race
White	1060 (78.58)	694 (78.33)	366 (79.05)	0.760
Other	289 (21.42)	192 (21.67)	97 (20.95)

¹Factors were compared by independent t test and χ² test for continuous and categorical variables, respectively.

Table 2 Prognostic significance for overall survival by univariate analysis of variables for stage IB and IIA patients¹

Variable	Stage IB		Stage IIA
	n	Log-rank	n	Log-rank
Age (yr)
≤ 65	444	0.000	270	0.000
> 65	442		193
Gender
Male	405	0.162	221	0.002
Female	481		242
Tumor size (mm)
21-30	584	0.258
31-40	302
41-70			332	0.013
> 70			131
Primary site
Head	486	0.000	147	0.004
Body	103		62
Tail	186		164
Other	111		90
Grade
I	221	0.000	127	0.000
II	335		149
III	164		66
IV	10		7
Unknown	156		114
Race
White	694	0.148	366	0.685
Other	192		97

¹Univariate analysis was done by Kaplan-Meier method.

Table 3 Prognostic significance for overall survival by multivariate analysis of variables for stage IB and IIA patients¹

Variable	Stage IB			Stage IIA
	RR	95%CI	P value	RR	95%CI	P value
Age	1.037	1.025-1.049	0.000	1.045	1.029-1.062	0.000
Gender (male vs female)	1.128	0.887-1.434	0.327	1.235	0.852-1.790	0.265
Tumor size	1.018	0.996-1.039	0.000	1.003	0.999-1.008	0.173
Primary site (head vs body-tail)	1.734	1.311-2.294	0.000	1.197	0.825-1.736	0.345
Grade (I + II vs III + IV)	0.570	0.443-0.734	0.104	0.490	0.333-0.721	0.000

¹Multivariate analysis was done with Cox proportional hazard regression model.