Table 2.
Proportion of anal cancer cases in the general population during 2001–2005 estimated to have HIV infection*
| Males | Females | |||
|---|---|---|---|---|
| Category | No. of cancers | HIV-infected, % of total (95% CI) | No. of cancers | HIV-infected, % of total (95% CI) |
| Total | 2705 | 28.4 (26.6 to 29.4) | 3864 | 1.2 (0.93 to 1.4) |
| Age at cancer diagnosis, y† | ||||
| 20–49 | 937 | 58.0 (52.9 to 60.7) | 777 | 3.7 (3.0 to 4.3) |
| 50–69 | 1164 | 18.8 (16.8 to 20.7) | 1779 | 0.90 (0.55 to 1.4) |
| >70 | 603 | 1.0 (0.59 to 1.6) | 1307 | 0 |
| White race | 2257 | 23.4 (22.0 to 24.6) | 3398 | 0.65 (0.50 to 0.85) |
| White race, by age, y | ||||
| 20–49 | 714 | 51.4 (47.0 to 55.4) | 653 | 1.9 (1.6 to 2.0) |
| 50–69 | 1000 | 15.7 (14.0 to 17.4) | 1566 | 0.63 (0.31 to 1.1) |
| >70 | 543 | 0.91 (0.44 to 1.6) | 1179 | 0 |
| Black race | 377 | 60.3 (52.2 to 64.4) | 363 | 6.4 (4.7 to 8.3) |
| Black race, by age, y | ||||
| 20–49 | 200 | 84.1 (71.8 to 89.1) | 99 | 17.2 (11.8 to 21.9) |
| 50–69 | 131 | 44.3 (35.6 to 53.8) | 172 | 3.6 (2.0 to 6.0) |
| >70 | 46 | 2.7 (2.1 to 3.7) | 91 | 0 |
| Squamous cell carcinoma‡ | 838 | 31.3 (32.2 to 35.6) | 3141 | 1.2 (1.1 to 1.7) |
| Squamous cell carcinoma, by age, y | ||||
| 20–49 | 928 | 56.6 (57.8 to 65.8) | 673 | 3.8 (3.7 to 4.9) |
| 50–69 | 377 | 20.7 (20.3 to 23.7) | 1512 | 0.74 (0.58 to 1.2) |
| >70 | 262 | 0.98 (0.72 to 1.9) | 960 | 0 |
| Adenocarcinoma‡ | 262 | 2.7 (0.84 to 4.6) | 246 | 0 |
| Adenocarcinoma, by age, y | ||||
| 20–49 | 41 | 8.5 (2.5 to 14.3) | 28 | 0 |
| 50–69 | 108 | 3.4 (0 to 8.5) | 78 | 0 |
| >70 | 113 | 0 | 140 | 0 |
* Proportions of anal cancer cases with HIV infection were estimated by dividing the number of HIV-infected anal cancer cases by the total number of anal cancer cases. CI = confidence interval.
† Results are not presented for the age 0–19 year group, as none of the eight anal cancer cases in this age group were HIV-infected. However, this age group was included in the total estimate and the overall estimates for whites, blacks, squamous cell carcinoma, and adenocarcinoma.
‡ Histology was classified using International Classification of Diseases for Oncology (ICD-O-3) codes: squamous cell carcinomas (ICD-O-3 codes 8050–8089), adenocarcinomas (8140–8309), carcinomas not otherwise specified (8010), and other histological subtypes.