TABLE 1.

Count and Incidence Rates of Invasive Anal Cancer by Histology and by Age, Race, Ethnicity, Sex, and Region—US, 1998 to 2003^*

	Total			Squamous†			Adenocarcinoma			Small Cell/Neuroendocrine
	Count (% of Total)	Rate‡	95% CI	Count	Rate	95% CI	Count	Rate	95% CI	Count	Rate	95% CI
Total	21,395 (100)	1.52	1.50–1.54	18,105	1.28	1.27–1.30	3080	0.22	0.21–0.23	210	0.02	0.01–0.02
Age, y
<50	5077 (23.7)	0.50	0.49–0.52	4716	0.47	0.45–0.48	305	0.03	0.03–0.03	56	0.01	0.00–0.01
50–64	6723 (31.4)	3.15	3.07–3.22	5921	2.77	2.70–2.84	732	0.34	0.32–0.37	70	0.03	0.03–0.04
≥65	9595 (44.8)	5.38	5.28–5.49	7468	4.19	4.10–4.29	2043	1.14	1.09–1.19	84	0.05	0.04–0.06
Sex
Male	8233 (38.5)	1.29	1.26–1.31	6497	1.00	0.98–1.03	1645	0.27	0.26–0.29	91	0.01	0.01–0.02
Female	13,162 (61.5)	1.70	1.67–1.73	11,607	1.51	1.48–1.54	1435	0.18	0.17–0.19	119	0.02	0.01–0.02
Race§
White	18,805 (87.9)	1.53	1.51–1.55	15,995	1.31	1.29–1.33	2637	0.21	0.20–0.22	173	0.01	0.01–0.02
Black	2009 (9.4)	1.58	1.51–1.66	1654	1.27	1.21–1.34	325	0.29	0.26–0.32	30	0.02	0.02–0.03
API	237 (1.1)	0.51	0.45–0.59	157	0.33	0.28–0.39	78	0.18	0.14–0.22	‖	‖	‖
Ethnicity
Non-Hispanic	19,895 (93.0)	1.53	1.51–1.55	16,844	1.30	1.28–1.32	2,863	0.22	0.21–0.23	188	0.02	0.01–0.02
Hispanic¶	1500 (7.0)	1.43	1.36–1.51	1261	1.19	1.12–1.26	217	0.22	0.19–0.25	22	0.02	0.01–0.03
Region
Northeast	4832 (22.6)	1.45	1.40–1.49	4088	1.23	1.19–1.27	698	0.20	0.19–0.22	46	0.01	0.01–0.02
Midwest	5186 (24.2)	1.36	1.32–1.39	4324	1.13	1.10–1.17	814	0.21	0.20–0.23	48	0.01	0.01–0.02
South	6418 (30.0)	1.67	1.63–1.71	5495	1.43	1.39–1.47	857	0.22	0.21–0.24	66	0.02	0.01–0.02
West	4959 (23.2)	1.61	1.57–1.66	4198	1.36	1.32–1.40	711	0.24	0.22–0.26	50	0.02	0.01–0.02

95% CI indicates 95% confidence interval; API, Asian/Pacific Islander.

^*Data are from 39 population-based cancer registries that participate in the National Program of Cancer Registries and/or the National Cancer Institute’s Surveillance, Epidemiology, and End Results program and meet the high-quality data criteria.¹⁰ These registries cover 83% of the US population.

^†Includes squamous cell carcinoma of the anus, anal canal, and rectum and the squamous cell variants classified as transitional cell, basaloid, and cloacogenic.

^‡Rates are per 100,000 population and are age-adjusted to the 2000 US standard population (19 age groups, Census P25-1130).

^§Race counts do not sum to total because cases in other race categories were excluded.

^‖Rates were suppressed if <16 cases were reported.

^¶Hispanic origin is not mutually exclusive of race categories (white, black, Asian/Pacific Islander).