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Background US population-based cancer registries can be used for surveillance of human papillomavirus (HPV) types found in HPV-associated cancers. Using this framework, HPV prevalence among high-grade cervical precancers and invasive cervical cancers were compared before and after HPV vaccine availability. Methods Archived tissue from 2 studies of cervical precancers and invasive cervical cancers diagnosed from 1993-2005 (prevaccine) were identified from 7 central cancer registries in Florida; Hawaii; Iowa; Kentucky; Louisiana; Los Angeles County, California; and Michigan; from 2014 through 2015 (postvaccine) cases were identified from 3 registries in Iowa, Kentucky, and Louisiana. HPV testing was performed using L1 consensus polymerase chain reaction analysis. HPV-type-specific prevalence was examined grouped by hierarchical attribution to vaccine types: HPV 16, 18, HPV 31, 33, 45, 52, 58, other oncogenic HPV types, and other types/HPV negative. Generalized logit models were used to compare HPV prevalence in the prevaccine study to the postvaccine study by patient age, adjusting for sampling factors. Results A total of 676 precancers (328 prevaccine and 348 postvaccine) and 1140 invasive cervical cancers (777 prevaccine and 363 postvaccine) were typed. No differences were observed in HPV-type prevalence by patient age between the 2 studies among precancers or invasive cancers. Conclusions The lack of reduction in vaccine-type prevalence between the 2 studies is likely explained by the low number of cases and low HPV vaccination coverage among women in the postvaccine study. Monitoring HPV-type prevalence through population-based strategies will continue to be important in evaluating the impact of the HPV vaccine.

Individuals with suppressed immune systems are at increased risk for developing a number of cancers, particularly those associated with viral infections. Solid organ transplant recipients and people infected with human immunodeficiency virus (HIV) are two populations with immunosuppression, predominantly related to deficits in T-cell function, and have elevated cancer risks (1). However, it is unknown whether immunosuppression also increases tumor aggressiveness, so that malignancies progress particularly quickly to advanced disease and death. The stage of cancer at the time of diagnosis reflects whether the tumor is localized, has spread to regional tissues or metastasized to more distant sites. Thus, assessing cancer stage in these populations may provide insight into the effect of immunosuppression on cancer progression. Prior research on cancer stage in HIV and transplant populations has been limited. One study, which compared cancers from an international transplant registry to cases from the U.S. general population, found that transplant recipients presented at later stages (2). Studies of HIV-infected people have demonstrated advanced stages at diagnosis for colorectal cancer (3;4) and lung cancer (5), but others had discrepant findings (6;7). No prior study has assessed cancer stage for multiple cancer sites among both HIV-infected individuals and transplant recipients. Though both the HIV-infected and transplant recipient populations experience deficits in cell-mediated immune function, the characteristics of these populations differ. HIV-infected people are more likely to be uninsured (8), affected by poverty (9), and more likely to exhibit social behaviors, such as drug use, that interfere with utilization of health services, including cancer screening. In contrast, health insurance is a requirement for organ transplantation, and transplant recipients undergo frequent monitoring of immunosuppressive medications and graft function. The parallel comparison of cancer stage in these two immune suppressed populations is important, because stage at diagnosis is influenced both by the tumor biology and the point during the course of cancer development when the tumor is first detected. People who receive less healthcare are more likely to be diagnosed with later stage disease, particularly for screen-detectable cancers (10), while people receiving increased surveillance are more likely to be diagnosed with earlier stage disease. Thus, a similar shift towards advanced stage in both populations would be best explained by an effect of immunosuppression on malignancy biology. Tumor grade (i.e., degree of differentiation manifested by tumor cells) is another marker of tumor aggressiveness that may be less impacted by the timing of cancer diagnosis; however, grade is not systematically ascertained for all tumor sites. In the current study, we compared the stages of cancers diagnosed in HIV-infected people and transplant recipients with the stages for other cancer patients (i.e., “immunocompetent” patients), using data from two large registry linkage studies. We also evaluated the distribution of tumor grade for select cancer sites. Additionally, among individuals with cancer within each population, we assessed whether indicators reflecting the degree of immunosuppression were associated with advanced stage.

BACKGROUND In American Indians (AIs), cancer is a leading cause of mortality, yet their disease burden is not fully understood due to unaddressed racial misclassification in cancer registries. This study describes cancer trends among AIs in Michigan, focusing on breast cancer, in a linked data set of Indian Health Service (IHS), tribal, and state cancer registry data adjusted for misclassification. METHODS AI status was based on reported race and linkage to IHS data and tribal registries. Data with complete linkage on all incident cancer cases in Michigan from 1995 to 2004 was used to calculate age-standardized incidence estimates for invasive all-site and female breast cancers stratified by racial group. For female breast cancers, stage- and age-specific incidence and percent distributions of early- versus late-stage cancers and age of diagnosis were calculated. RESULTS More than 50% of all AI cases were identified through IHS and/or tribal linkage. In the linked data, AIs had the lowest rates of all-sites and breast cancer. For breast cancers, AI women had a greater late-stage cancer burden and a younger mean age of diagnosis as compared to whites. Although the age-specific rate for whites was greater than for AI women in nearly all age groups, the difference in hazard ratio increased with increasing age. CONCLUSIONS Our state-specific information will help formulate effective, tailored cancer prevention strategies to this population in Michigan. The data linkages used in our study are crucial for generating accurate rates and can be effective in addressing misclassification of the AI population and formulating cancer prevention strategies for AI nationwide. Cancer 2014;120:1847–1853. © 2014 American Cancer Society.

BACKGROUND. With the recent licensure of a vaccine that protects against human papillomavirus (HPV) types 16 and 18, US women are expected to experience lower rates of cervical cancer. However, surveillance systems must be in place in the US to measure the real-world effectiveness of vaccination programs. Although population-based registries will provide invasive cervical cancer (ICC) incidence and burden data, the impact of HPV vaccine on cervical cancer will not be measurable for several decades. Cervical carcinoma in situ (CIS), a cervical precancer and the immediate precursor to ICC, is an earlier presentation of HPV-related cervical disease that affects a much larger number of women, and monitoring trends in CIS could provide an earlier measure of HPV vaccine effectiveness. Currently, registries do not collect data on CIS except for the state cancer registry in Michigan, which has been continually collecting CIS data since 1985. METHODS. All cases of CIS and ICC diagnosed from 1985 through 2003 in the Michigan registry were identified. Available data include age at diagnosis, race, morphologic tumor type, and tumor behavior. RESULTS. There were 58,144 cases of CIS and ICC, of which 48,272 (83.0%) were CIS and 9872 (17.0%) were ICC. There were 2928 CIS cases and 413 ICC cases diagnosed in Michigan during 2003, compared with 1577 CIS and 516 ICC cases reported in 1985. Age-adjusted CIS rates increased from 1985 (31.7 per 100,000) to 2003 (59.2 per 100,000); rates of CIS were highest among women age

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.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.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).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.

BACKGROUND: Racial disparities in survival from breast and prostate cancer are well established; however, the roles of societal/socioeconomic factors and innate/genetic factors in explaining the disparities remain unclear. One approach for evaluating the relative importance of societal and innate factors is to quantify how the magnitude of racial disparities changes according to the geographic scales at which data are aggregated. Disappearance of racial disparities for some levels of aggregation would suggest that modifiable factors not inherent at the individual level are responsible for the disparities. METHODS: The Michigan Cancer Surveillance Program compiled a dataset from 1985 to 2002 that included 124,218 breast cancer cases and 120,615 prostate cancer cases with 5-year survival rates of 78% and 75%, respectively. Absolute and relative differences in survival rates for whites and blacks were quantified across different geographic scales using statistics that adjusted for population size to account for the small numbers problem common with minority populations. RESULTS: Whites experienced significantly higher survival rates for prostate and breast cancer compared with blacks throughout much of southern Michigan in analyses conducted using federal House legislative districts; however, in smaller geographic units (state House legislative districts and community-defined neighborhoods), disparities diminished and virtually disappeared. CONCLUSIONS: The current results suggest that modifiable societal factors are responsible for apparent racial disparities in breast and prostate cancer survival observed at larger geographic scales. This research presents a novel strategy for taking advantage of inconsistencies across geographic scales to evaluate the relative importance of innate and societal-level factors in explaining racial disparities in cancer survival. Cancer 2009. © 2009 American Cancer Society.