HIV-associated anal cancer: has highly active antiretroviral therapy reduced the incidence or improved the outcome?

BACKGROUND

Highly active antiretroviral therapy (HAART) has reduced the incidence and improved the survival of patients with Kaposi sarcoma and AIDS-related non-Hodgkin lymphoma. We wished to evaluate its effects on incidence and survival in HIV-associated anal cancer.

METHODS

We measured the incidence and survival of patients with invasive anal cancer from our prospective cohort of 8640 HIV-seropositive individuals.

RESULTS

In our cohort of 8640 HIV-seropositive individuals, the incidence of invasive anal cancer (diagnosed in 26 patients) is 60 per 100,000 patient-years. This is 120 times higher than in the age- and gender-matched general population. The incidence of invasive anal cancer in the HIV cohort was 35 (95% confidence interval CI: 15-72) per 100,000 patient-years of follow-up in the pre-HAARTera (1984-1995) and 92 (95% CI: 52-149) per 100,000 patient-years of follow-up in the post-HAARTera (1996-2003) (P > 0.05). These figures are significantly higher than those for the general population (P < 0.001 for both) and give a relative risk of 67 and 176 in the pre- and post-HAART eras, respectively, compared with the general population. The 5-year overall survival is 47% (95% CI: 24%-70%), and the 5-year disease-free survival is 66% (95% CI: 45%-87%). There is no difference in overall survival between the pre- and post-HAART eras (log rank P = 0.19).

CONCLUSIONS

Unlike other HIV-associated cancers, there has been no significant change in the incidence, clinical features, or overall survival since the introduction of HAART.