Nomogram for overall survival in ampullary adenocarcinoma using the surveillance, epidemiology, and end results database and external validation

Table 2 Univariate and multivariate Cox analyses for overall survival in the training group

Variable	Univariate analysis			Multivariate analysis
	HR	95%CI	P value	HR	95%CI	P value
Age
< 50	Reference
50-59	1.25	0.91-1.71	0.17	1.19	0.86-1.64	0.30
60-69	1.44	1.07-1.953	< 0.05	1.10	0.81-1.50	0.55
70-79	1.93	1.43-2.61	< 0.05	1.62	1.19-2.20	< 0.05
≥ 80	3.35	2.48-4.53	< 0.05	1.83	1.31-2.56	< 0.05
Sex
Female	Reference
Male	1.08	0.95-1.23	0.23	1.20	1.03-1.38	< 0.05
Race
White	Reference
Black	1.09	0.86-1.38	0.46	1.28	1.00-1.65	< 0.05
Unknown	0.71	0.59-0.86	< 0.05	0.90	0.74-1.09	0.29
SEER stage
Localized	Reference
Regional	0.98	0.80-1.19	0.81	1.30	0.89-1.90	0.18
Distant	2.17	1.76-2.68	< 0.05	1.80	0.82-3.94	0.14
Unknown	3.01	2.12-4.28	< 0.05	1.49	0.82-2.71	0.19
Surgical modality
None	Reference
Surgical removal of primary site	0.21	0.18-0.25	< 0.05	0.35	0.25-0.50	< 0.05
Radical surgery	0.22	0.19-0.26	< 0.05	0.38	0.26-0.54	< 0.05
Radiation
No	Reference
Yes	0.89	0.76-1.05	0.16
Chemotherapy
No	Reference
Yes	0.81	0.71-0.92	< 0.05	0.61	0.52-0.71	< 0.05
Bone metastasis
No	Reference
Yes	2.86	0.71-11.46	0.14
Brain metastasis
No	Reference
Yes	6.57	2.46-17.58	< 0.05	4.18	1.42-12.33	< 0.05
Liver metastasis
No	Reference
Yes	3.55	2.86-4.42	< 0.05	1.01	0.68-1.51	0.96
Lung metastasis
No	Reference
Yes	3.27	2.23-4.80	< 0.05	0.63	0.38-1.06	0.08
Tumor size
< 2 cm	Reference
> 2 cm	1.40	1.20-1.63	< 0.05	1.04	0.88-1.23	0.63
Unknown	3.12	2.61-3.74	< 0.05	1.28	1.02-1.63	< 0.05
LNR
0	Reference
0-0.5	2.04	1.71-2.42	< 0.05	1.49	1.02-2.19	< 0.05
0.5-1	5.11	3.79-6.89	< 0.05	2.99	1.90-4.72	< 0.05
Unknown	6.02	5.05-7.18	< 0.05	2.22	1.55-3.17	< 0.05
Marital status
Single	Reference
Divorced	1.15	0.89-1.50	0.28	1.03	0.79-1.34	0.85
Married	0.96	0.80-1.15	0.66	0.97	0.80-1.17	0.74
Widowed	1.66	1.33-2.06	< 0.05	1.08	0.84-1.38	0.55
Unknown	1.02	0.70-1.48	0.91	0.88	0.60-1.29	0.52
T stage
T1	Reference
T2	0.64	0.52-0.78	< 0.05	0.97	0.67-1.39	0.87
T3	0.98	0.80-1.19	0.83	1.72	0.79-3.73	0.17
T4	1.44	1.19-1.74	< 0.05	1.77	1.11-2.81	< 0.05
Unknown	2.65	2.01-3.49	< 0.05	0.73	0.44-1.22	0.23
N stage
N0	Reference
N1	1.25	1.10-1.43	< 0.05	1.23	0.87-1.74	0.24
Unknown	3.14	2.30-4.29	< 0.05	1.12	0.79-1.59	0.53
M stage
M0	Reference
M1	3.89	3.24-4.66	< 0.05	1.46	0.71-3.00	0.31
Extension
Localized	Reference
Duodenal wall	0.36	0.29-0.44	< 0.05	1.02	0.74-1.40	0.92
Pancreas	0.53	0.42-0.66	< 0.05	0.87	0.45-1.69	0.68
Common bile duct	0.78	0.58-1.07	0.12	0.53	0.36-0.80	< 0.05
Invasive tumor confined	0.66	0.52-0.84	< 0.05	0.83	0.39-1.77	0.63
Extension to other adjacent organs	1.39	1.03-1.87	< 0.05
Tumor differentiation
Well-differentiated	Reference
Moderately differentiated	1.19	0.93-1.52	0.16	1.07	0.83-1.38	0.59
Poorly differentiated	1.81	1.41-2.34	< 0.05	1.65	1.26-2.15	< 0.05
Undifferentiated	1.62	0.86-3.04	0.14	0.98	0.51-1.86	0.94
Unknown	2.54	1.94-3.33	< 0.05	1.03	0.77-1.38	0.83

CI: Confidence interval; HR: Hazard ratio; LNR: Lymph node ratio (refers to the ratio of regional nodes that were positive vs those examined); SEER: Surveillance, epidemiology, and end results.