Disparities in the treatment and outcomes of lung cancer among HIV-infected individuals

Abstract

Objectives: HIV-infected people have elevated risk for lung cancer and higher mortality following cancer diagnosis than HIV-uninfected individuals. It is unclear whether HIV-infected individuals with lung cancer receive similar cancer treatment as HIV-uninfected individuals.

Design/methods: We studied adults more than 18 years of age with lung cancer reported to the Texas Cancer Registry (N = 156 930) from 1995 to 2009. HIV status was determined by linkage with the Texas enhanced HIV/AIDS Reporting System. For nonsmall cell lung cancer (NSCLC) cases, we identified predictors of cancer treatment using logistic regression. We used Cox regression to evaluate effects of HIV and cancer treatment on mortality.

Results: Compared with HIV-uninfected lung cancer patients (N = 156 593), HIV-infected lung cancer patients (N = 337) were more frequently young, non-Hispanic black, men, and with distant stage disease. HIV-infected NSCLC patients less frequently received cancer treatment than HIV-uninfected patients [60.3 vs. 77.5%; odds ratio 0.39, 95% confidence interval (CI) 0.30-0.52, after adjustment for diagnosis year, age, sex, race, stage, and histologic subtype]. HIV infection was associated with higher lung cancer-specific mortality (hazard ratio 1.34, 95% CI 1.15-1.56, adjusted for demographics and tumor characteristics). Inclusion of cancer treatment in adjusted models slightly attenuated the effect of HIV on lung cancer-specific mortality (hazard ratio 1.25; 95% CI 1.06-1.47). Also, there was a suggestion that HIV was more strongly associated with mortality among untreated than among treated patients (adjusted hazard ratio 1.32 vs. 1.16, P-interaction = 0.34).

Conclusion: HIV-infected NSCLC patients were less frequently treated for lung cancer than HIV-uninfected patients, which may have affected survival.

Fig. 1. Survival following diagnosis of nonsmall cell lung cancer, according to HIV status and cancer treatment

(a) Treated lung cancer patients. (b) Untreated lung cancer patients. The figure presents Kaplan–Meier curves illustrating overall survival following lung cancer diagnosis, for patients who received cancer treatment (a) or did not receive cancer treatment (b). The numbers below the panels indicate the number at risk at defined times following lung cancer diagnosis. ‘HIV neg’, HIV-uninfected patients; ‘HIV pos’, HIV-infected patients.