Clinicopathologic Features and Outcome of Adenocarcinoma of the Anal Canal: A Population-Based Study

Table 2

Cox hazard regression of predictors of survival.

Variable	HR	95% of HR	value
Age
0–40 years (reference)	1
41–60 years	0.97	0.67–1.38	0.866
61–80 years	1.62	1.15–2.30	0.006
>81 years	3.79	2.65–5.41	<0.01
Race
American Indians/Alaska Natives (reference)	1
Whites	1.42	0.80–2.56	0.21
African Americans	1.62	0.90–2.90	0.29
Asians/Pacific Islanders	1.19	0.60–2.198	0.30
Gender
Female (reference)	1
Male	1.08	0.97–1.20	0.13
Stage
In situ (reference)	1
Localized only	0.87	0.75–1.00	0.06
Regional spread by direct extension only	1.27	1.08–1.49	0.03
Distant site(s)/node(s) involved	2.8	2.35–3.36	<0.01
Unknown	2.1	1.76–2.76	<0.01
Grade
Well differentiated (reference)	1
Moderately differentiated;	1.37	1.15–1.64	<0.01
Poorly differentiated; differentiated	2.15	1.76–2.63	<0.01
Undifferentiated; anaplastic	1.81	1.37–2.88	0.01
Cell type not determined	1.11	0.92–1.34	0.24
Surgery
Yes (reference)	1
No	0.38	0.34–0.42	<0.01