Cancer stage at diagnosis in patients infected with the human immunodeficiency virus and transplant recipients.

BACKGROUND: It is unknown whether immunosuppression results in more aggressive, advanced stage cancers. Because cancer stage is influenced both by tumor biology and medical surveillance, the authors assessed cancer stage in individuals infected with the human immunodeficiency virus (HIV) and solid organ transplant recipients, 2 immunosuppressed groups with differences in their health care use. METHODS: The authors used data on all cases of 15 cancer types diagnosed during 1996 through 2010 in 2 studies that linked US cancer registries with HIV and transplant registries. Odds ratios (ORs) for advanced (vs local) disease were estimated comparing HIV and transplant populations with immunocompetent individuals in polytomous logistic regression models adjusted for age, sex, race, registry, and year. RESULTS: A total of 8411 of 4.5 million cancer cases occurred in HIV-infected individuals and 7322 of 6.4 million cancer cases occurred in transplant recipients. Compared with immunocompetent patients with cancer, those infected with HIV were more likely to be diagnosed with distant stage lung (OR, 1.13), female breast (OR, 1.99), and prostate (OR, 1.57) cancers, whereas transplant recipients had fewer distant stage lung (OR, 0.54), female breast (OR, 0.75), and prostate (OR, 0.72) cancers. Both immunosuppressed populations had a shift toward advanced stage melanoma (ORs of 1.97 for HIV-infected individuals and 1.82 for transplant recipients) and bladder cancer (ORs of 1.42 for HIV-infected individuals and 1.54 for transplant recipients). CONCLUSIONS: Bladder cancer and melanoma were more likely to be diagnosed at a nonlocal stage in both HIV-infected individuals and transplant recipients, suggesting a role for immunosuppression in their progression. In addition, we observed a shift for some common cancers toward later stages in HIV-infected individuals and toward earlier stages in transplant recipients, which is consistent with differential access to medical care or surveillance.

Rural-urban differences in colon cancer risk in blacks and whites: the North Carolina Colon Cancer Study.

CONTEXT: Geographic and racial variations in cancer incidence have been observed. Studies of colorectal carcinoma indicate a higher incidence and mortality rate for blacks than for whites in the United States. PURPOSE: We evaluated the effect of rural versus urban residence on colon cancer risk and stage of disease at diagnosis in blacks and whites. METHODS: Interviews were conducted with 558 colon cancer cases and 952 controls enrolled in the North Carolina Colon Cancer Study, a population-based case-control study of blacks and whites residing in 33 contiguous counties. FINDINGS: Residence in a rural area was associated with increased colon cancer risk (odds ratio, 1.4; 95% confidence interval, 1.1-1.8). This association was no longer significant after controlling for recent use of colorectal cancer screening tests (odds ratio, 1.2; 95% confidence interval, 0.9-1.6). Risk estimates were not modified by race nor were they markedly different for extent of disease at diagnosis. However, colorectal cancer screening rates were lower for blacks than for whites. CONCLUSION: Our findings suggest that rural blacks and whites are at increased risk of colon cancer regardless of stage of disease at diagnosis than their urban counterparts; this relationship may be mediated by screening behavior.