817 Lung Cancer Incidence and Survival in Persons with AIDS in the U.S. (1978-1996) B. Brown, R. J. Biggar, J. J. Goedert, E. A. Engels* Natl Cancer Inst, Rockville, MD
Background: Persons with HIV/AIDS have an elevated risk of lung cancer. The effects of immune suppression or other factors on lung cancer risk and subsequent survival in this population have been little studied.
Methods: The AIDS Cancer Match Registry is a population-based cohort study of cancer in persons with AIDS in 11 U.S. geographic areas. We used data from this study to examine lung cancer incidence in the 2 yrs after AIDS onset among 185,691 adults with AIDS (1978-1996). We also studied survival in 243 patients diagnosed with lung cancer in the 5 yrs after AIDS onset. Poisson and Cox regression were used for incidence and survival analyses, respectively.
Results: In the 2 yrs post-AIDS onset, 179 persons developed lung cancer (incidence 0.75 per 1000 person-yrs; relative risk 3.36 vs the general population). Compared with whites (incidence 0.76), incidence was higher in African Americans (1.06, p = 0.03) and lower in Hispanics (0.26, p = 0.0004). Overall, males and females had similar incidence (p = 0.81), but incidence was higher in male injection drug users than homosexual males (0.99 vs 0.64, p = 0.004). Incidence increased with age (p < 0.0001). Among the 36% of subjects with available data, CD4 count at AIDS was not significantly related to incidence (p = 0.18). Of the 159 cancers with specified histology, 94% were non-small cell and 6% were small cell carcinoma vs 85% non-small cell and 15% small cell carcinoma among lung cancers in the HIV-uninfected population (SEER data). Following lung cancer diagnosis, survival in persons with AIDS was poor: 97% died and median survival was 3 mos vs 9 mos reported for HIV-uninfected persons (SEER data). Survival was unrelated to lung cancer histology, CD4 count at AIDS, or time from AIDS onset to lung cancer diagnosis.
Conclusion: Lung cancer is 3 times more common in persons with AIDS than in the general population, which likely reflects a high prevalence or intensity of smoking in HIV-infected persons. Lung cancer incidence is especially high among African Americans and injection drug users. Risk appears unrelated to HIV-induced immunosuppression. Survival among persons with AIDS and lung cancer is extremely poor. Because the incidence of lung cancer among HIV-infected persons may increase as this population ages, additional research should be directed at understanding smoking behaviors in this population and factors responsible for their poor post-cancer survival.
