French study raises importance of early screening for anal cancer in HIV-positive people
9 September 2006. Related: Conference reports, Coinfections and complications, Cancer and HIV, World AIDS 16 Toronto 2006.
Simon Collins, HIV i-Base
Christophe Piketty and colleagues looked at the impact of HAART on incidence of anal cancer diagnosed between 1992 and 2003 in HIV-positive patients from the French Database of HIV (FHDH). The analysis looked at pre-HAART, early HAART, and later HAART time periods. 92 cases were identified (84 men, 8 women) from almost 75,000 patients in the database.
Among men, 74% were men who have sex with men. The median age at diagnosis was 42.4 years [IQR: 36.0-49.3]; the median CD4 cell count was 247 cells/mm3 [IQR: 135-420]; the median nadir CD4 cell count was 80 cells/mm3 [IQR: 21-174] and 39% of the cases had presented an AIDS defining event prior to the anal cancer diagnosis. At diagnosis, 71 patients (77%) had been receiving HAART for over five years (median 65 months [IQR: 44-77]).
Table 1: Changes in incidence rate of anal cancer
| Whole database | 1992-March 1996 | April 1996-1998 | 1999-2003 |
|---|---|---|---|
| Pt/yr follow-up | 104,648 | 102,798 | 204,298 |
| No. cases | 9 | 12 | 69 |
| Incidence 100,00 Pt/yr | 8.6 [3.0, 14.2] | 11.7 [5.1, 18.3] | 33.8 [33.8, 41.7] |
| Relative risk | 1.0 | 1.36 [0.57, 3.22] | 3.93 [1.96, 7.87] |
| MSM | 1992-March 1996 | April 1996-1998 | 1999-2003 |
| Pt/yr follow-up | 37,923 | 37,046 | 72,647 |
| No. cases | 6 | 10 | 44 |
| Incidence 100,00 Pt/yr | 15.8 [3.2, 28.5] | 27.0 [10.3, 43.7] | 60.6 [42.7, 78.5] |
| Relative risk | 1.0 | 1.71 [0.62, 4.69] | 3.83 [1.63, 8.98] |
The incidence of anal cancer increased, in both the whole HIV-cohort, and in HIV-positive men who have sex with men (MSM), though the risk in MSM was approximately twice as high, and is detailed in Table 1. The increase in all rates was explained by the investigators by longer life expectancy conferred by HAART, in that people are living long enough for malignancies to develop. The survival probability after the anal cancer diagnosis was 74%+/-6% at 3 years.
The conclusion drawn by the researchers was that as HAART exhibited no favorable effect on the incidence of anal cancer, this supported the urgent need for developing anal cancer screening programs for HIV-infected individuals.
Reference:
- Piketty C, Selinger-Leneman H, Grabar S et al. Dramatic increase in the incidence of anal cancer despite HAART in the French hospital database of HIV. XVI International AIDS Conference, Toronto, Canada. 13 – 18 August 2006. Oral abstract TUAB0305.