Metastatic pancreatic adenocarcinomas could be classified into M1a and M1b category by the number of metastatic organs

Table 3 Multivariable analysis for patients with metastatic pancreatic adenocarcinomas

Variables	Single Metastasis (n = 9425)^c		Multiple Metastases (n = 2460)^c
Variables	HR^a (95% CI^b)	P value	HR (95% CI)	P value
Gender
Male	Reference		Reference
Female	0.889 (0.844–0.936)	< 0.001	0.869 (0.786–0.961)	0.006
Age (years)
≤ 65	Reference		Reference
> 65	1.333 (1.267–1.403)	< 0.001	1.259 (1.139–1.391)	< 0.001
Race
White	Reference		Reference
Black	1.058 (0.983–1.140)	0.132	0.984 (0.845–1.145)	0.834
Others	0.969 (0.879–1.069)	0.529	1.073 (0.895–1.286)	0.447
Tumor location
Head	Reference		Reference
Body/tail	1.053 (0.995–1.114)	0.073	1.041 (0.924–1.172)	0.510
Others	1.076 (1.005–1.152)	0.036	1.045 (0.911–1.199)	0.530
Marital status
Married	Reference		Reference
Unmarried/unknown	1.164 (1.104–1.226)	< 0.001	1.147 (1.036–1.270)	0.008
Grade
Well/moderately differentiated	Reference		Reference
Poorly differentiated/undifferentiated	1.952 (1.757–2.169)	< 0.001	1.522 (1.218–1.901)	< 0.001
Unknown	1.781 (1.637–1.937)	< 0.001	1.440 (1.201–1.726)	< 0.001
Tumor size	1.001 (1.000–1.002)	0.156	1.000 (0.998–1.001)	0.490
Surgery
No	Reference		Reference
Yes	0.460 (0.405–0.522)	< 0.001	0.773 (0.551–1.083)	0.134
Chemotherapy
No	Reference		Reference
Yes	0.428 (0.406–0.451)	< 0.001	0.360 (0.324–0.401)	< 0.001
Radiotherapy
No	Reference		Reference
Yes	0.819 (0.719–0.932)	0.003	0.799 (0.673–0.948)	0.010

^aHR hazard ratio
^bCI confidence interval
^cThe number of events for patients with single metastasis and multiple metastases were 8077 and 2229, respectively

ISSN: 1471-230X