Abstract 3446: Aspirin, non-steroidal anti-inflammatory drugs (NSAIDs) and the risk of glioma: Results from the Glioma International Case Control Study

Background: Numerous epidemiologic studies have examined the association between aspirin (ASA), non-steroid anti-inflammatory drugs (NSAIDs) and the development of glioma, but the results have been inconsistent. The goal of this study was to evaluate the relationship between the intake of these drugs and glioma risk in a large, international case-control study.

Methods: Between 2010 and 2015, the Glioma International Case-Control Study (GICC) recruited newly diagnosed glioma cases and matched controls in 14 different sites across five countries. Each subject was interviewed using a standardized questionnaire to obtain NSAIDs and ASA use. We examined the associations between ever use (at least > 6 months), duration of drug use and glioma histology. Ever use data on 4533 glioma cases and 4171 controls was combined using maximum likelihood estimation/restricted maximum likelihood meta-analysis methods. Furthermore, based on a priori hypotheses, we performed subgroup analyses based on gender and glioma histological grades.

Results: Use of ASA for > 6 months was associated with a 33% lower glioma risk compared to those who never took it (adjusted Meta-OR 0.67, 95% CI 0.54-0.83). Duration of intake showed a significant trend test (p < 0.0001), with ORs became lower for increasing number of years of ASA use. In subgroup analyses, intake of ASA was significantly associated with glioma risk in both men and women (adjusted Meta-OR = 0.65, 95% CI 0.51-0.84 for men; adjusted Meta-OR = 0.74, 95% CI 0.58-0.93 for women). ASA intake was protective for grade IV glioma (glioblastoma) and grade II/III glioma (adjusted meta-OR 0.63, 95% CI 0.5-0.8 for glioblastoma; adjusted meta-OR 0.67, 95% CI 0.50 - 0.89 for grade II/III glioma). For NSAIDs intake, ever use > 6 months was not associated with glioma risk (adjusted meta-OR 0.87, 95% CI 0.71-1.07). However, NSAIDs use was protective for women (adjusted meta-OR 0.72, 95% CI 0.55-0.93) in subgroup analyses but not for men (adjusted meta-OR 1.03; 95% CI 0.86-1.23). The interaction between gender, NSAIDs and glioma risk was significant (p-value 0.0076).. Sensitivity analyses excluding those who took ASA or NSAIDs within the past 12 months for headache, and the removal of proxy respondents did not change our results.

Conclusion: ASA was associated with a significant protective effect for glioma, but NSAIDs were only associated with reduced glioma risk in women. Given the possibility of recall bias in case-control studies of brain tumors, we may verify dosage and duration of drug intake in those countries with electronic pharmacy records within the GICC.

Citation Format: Rose K. Lai, Renke Zhou, E. Susan Amirian, Christoffer Johansen, Michael E. Scheurer, Georgina N. Armstrong, Ching C. Lau, Elizabeth B. Claus, Jill S. Barnholtz-Sloan, Dora Il’yasova, Joellen Schildkraut, Francis Ali-Osman, Siegal Sadetzki, Richard Houlston, Robert B. Jenkins, Daniel Lachance, Sara H. Olson, Jonine L. Bernstein, Ryan T. Merrell, Margaret R. Wrensch, Faith G. Davis, Sanjay Shete, Christopher I. Amos, Beatrice S. Melin, Melissa Bondy. Aspirin, non-steroidal anti-inflammatory drugs (NSAIDs) and the risk of glioma: Results from the Glioma International Case Control Study. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3446.

History of chickenpox in glioma risk: a report from the glioma international case-control study (GICC)

Varicella zoster virus (VZV) is a neurotropic α-herpesvirus that causes chickenpox and establishes life-long latency in the cranial nerve and dorsal root ganglia of the host. To date, VZV is the only virus consistently reported to have an inverse association with glioma. The Glioma International Case-Control Study (GICC) is a large, multisite consortium with data on 4533 cases and 4171 controls collected across five countries. Here, we utilized the GICC data to confirm the previously reported associations between history of chickenpox and glioma risk in one of the largest studies to date on this topic. Using two-stage random-effects restricted maximum likelihood modeling, we found that a positive history of chickenpox was associated with a 21% lower glioma risk, adjusting for age and sex (95% confidence intervals (CI): 0.65-0.96). Furthermore, the protective effect of chickenpox was stronger for high-grade gliomas. Our study provides additional evidence that the observed protective effect of chickenpox against glioma is unlikely to be coincidental. Future studies, including meta-analyses of the literature and investigations of the potential biological mechanism, are warranted.

Approaching a Scientific Consensus on the Association between Allergies and Glioma Risk: A Report from the Glioma International Case-Control Study

BACKGROUND

Several previous studies have found inverse associations between glioma susceptibility and a history of allergies or other atopic conditions. Some evidence indicates that respiratory allergies are likely to be particularly relevant with regard to glioma risk. Using data from the Glioma International Case-Control Study (GICC), we examined the effects of respiratory allergies and other atopic conditions on glioma risk.

METHODS

The GICC contains detailed information on history of atopic conditions for 4,533 cases and 4,171 controls, recruited from 14 study sites across five countries. Using two-stage random-effects restricted maximum likelihood modeling to calculate meta-analysis ORs, we examined the associations between glioma and allergy status, respiratory allergy status, asthma, and eczema.

RESULTS

Having a history of respiratory allergies was associated with an approximately 30% lower glioma risk, compared with not having respiratory allergies (mOR, 0.72; 95% confidence interval, 0.58-0.90). This association was similar when restricting to high-grade glioma cases. Asthma and eczema were also significantly protective against glioma.

CONCLUSION

A substantial amount of data on the inverse association between atopic conditions and glioma has accumulated, and findings from the GICC study further strengthen the existing evidence that the relationship between atopy and glioma is unlikely to be coincidental.

IMPACT

As the literature approaches a consensus on the impact of allergies in glioma risk, future research can begin to shift focus to what the underlying biologic mechanism behind this association may be, which could, in turn, yield new opportunities for immunotherapy or cancer prevention.

The Glioma International Case-Control Study: A Report From the Genetic Epidemiology of Glioma International Consortium

Decades of research have established only a few etiological factors for glioma, which is a rare and highly fatal brain cancer. Common methodological challenges among glioma studies include small sample sizes, heterogeneity of tumor subtypes, and retrospective exposure assessment. Here, we briefly describe the Glioma International Case-Control (GICC) Study (recruitment, 2010-2013), a study being conducted by the Genetic Epidemiology of Glioma International Consortium that integrates data from multiple data collection sites, uses a common protocol and questionnaire, and includes biospecimen collection. To our knowledge, the GICC Study is the largest glioma study to date that includes collection of blood samples, which will allow for genetic analysis and interrogation of gene-environment interactions.

Association between Time on Protease Inhibitors and the Incidence of Squamous Cell Carcinoma of the Anus among U.S. Male Veterans

Protease inhibitors (PIs) have been shown to have anti-tumor activity in addition to their antiretroviral properties. We sought to assess the association between PI use and the incidence of squamous cell carcinoma of the anus (SCCA) in HIV-infected individuals. We performed a retrospective cohort study among male US veterans diagnosed with HIV who were diagnosed between 1985 and 2010, using the Veterans Affairs HIV Clinical Case Registry (CCR). We calculated hazards ratios associated with PI use (both as percent time on PI and as 12-month intervals of PI use), utilizing time-dependent Cox models. We adjusted for risk factors, including age, race, year of enrolment into CCR, recent and nadir CD4, and percent time undetectable HIV viral load. A total of 28, 886 HIV-infected men met inclusion criteria. Of these, 373 were newly diagnosed with SCCA during the study period. In multivariate analysis, increasing percent time on PIs was associated with an increased risk of SCCA (aHR 1.07; 95% CI = 1.03–1.10 per 10% increase in time on PI). Poor immunologic recovery and virologic control, a history of condylomata acuminata, and CCR enrolment in the late combined antiretroviral therapy era were also associated with increased SCCA risk. Increasing percent time on a PI-based combined antiretroviral therapy regimen may be associated with an increased risk of developing SCCA in HIV-infected male US veterans. Future studies, better accounting for HIV control and treatment compliance, are necessary to further clarify this association.

Abstract 2879: Profiling of lung microbial communities in lung cancer and chronic obstructive pulmonary disease patients

Background: The composition and structure of site-specific microbiota have recently been described as a biomarker associated with a variety of high impact diseases including cancer. This study sought to identify lung microbial signatures in smokers with lung cancer (LC) and/or chronic obstructive pulmonary disease (COPD).

Material and Methods: We employed 16S rRNA gene compositional analysis to compare the microbiota in Optimal Cutting Temperature (OCT) embedded biopsies of lung-tissue from 30 smokers, including 10 patients with LC only, 10 patients with COPD only, and 10 patients with both LC and COPD, selected from a longitudinal study of COPD exacerbation conducted in Houston, Texas, during 2005 to 2012.

Results: Microbial signatures calculated based on the 16S rRNA gene data showed that patients with COPD only presented a very distinct microbial structure defined by a significantly lower Shannon Diversity Index compared to patients with LC only (P = 0.04), and patients with both LC and COPD (P = 0.003), suggesting lower bacterial richness and evenness. Furthermore, biopsies from patients with COPD only were characterized by an increased prevalence of Acinetobacter (P < 0.0001) and Acidovorax (P < 0.0001), and a lower prevalence of Bifidobacterium, Streptococcus, and Ruminococcus species compared to patients with LC only and those with both LC and COPD. However, patients with both COPD and LC were indistinguishable from those with LC only.

Conclusions: This study is the first and largest to examine the composition of the lung microbiome in smokers with LC and/or COPD. Specific bacterial signatures were identified in patients with LC only and those with both COPD and LC demonstrating that the lung microbiome can be used as a biomarker for the two diseases. Altogether, we observed altered lung microbiota of COPD and LC, but whether this is involved in disease causation or is a consequence of host selection remains unclear.

Citation Format: Yanhong Liu, Nadim J Ajami, Matthew C Wong, Michael Scheurer, E. Susan Amirian, Joseph F Petrosino, Margaret R Spitz, Melissa L Bondy, Farrah Kheradmand. Profiling of lung microbial communities in lung cancer and chronic obstructive pulmonary disease patients. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2879. doi:10.1158/1538-7445.AM2015-2879

Targeted sequencing in chromosome 17q linkage region identifies familial glioma candidates in the Gliogene Consortium

Glioma is a rare, but highly fatal, cancer that accounts for the majority of malignant primary brain tumors. Inherited predisposition to glioma has been consistently observed within non-syndromic families. Our previous studies, which involved non-parametric and parametric linkage analyses, both yielded significant linkage peaks on chromosome 17q. Here, we use data from next generation and Sanger sequencing to identify familial glioma candidate genes and variants on chromosome 17q for further investigation. We applied a filtering schema to narrow the original list of 4830 annotated variants down to 21 very rare (<0.1% frequency), non-synonymous variants. Our findings implicate the MYO19 and KIF18B genes and rare variants in SPAG9 and RUNDC1 as candidates worthy of further investigation. Burden testing and functional studies are planned.

Abstract C90: Colorectal cancer among Hispanics in the U.S.: Nativity disparities in stage at diagnosis and survival

Introduction: Compared to non-Hispanic whites, Hispanics in the U.S. are significantly more likely to be diagnosed with late-stage colorectal cancer (CRC) and have a higher CRC-specific mortality hazard. While the low CRC screening rates among Hispanics (29%) are known to be lowest among foreign-born individuals (22%), few studies have examined CRC disparities by nativity. Here we examine differences in late-stage CRC diagnosis and survival among U.S.- and foreign-born Hispanics.

Methods: We used data from the Surveillance, Epidemiology, and End Results (SEER) program. Cases were Hispanic men and women diagnosed with primary invasive CRC between 1988 and 2008. Nativity was based on place of birth and was categorized as U.S.- versus foreign-born. Missing nativity values were imputed using multiple imputation by logistic regression, a strategy with high sensitivity (91%) and specificity (90%) for detecting foreign-born status. Distant and regional tumors were classified as late-stage; local tumors were classified as early-stage. Multivariable logistic regression was used to assess the association between late-stage diagnosis and nativity after adjusting for demographic characteristics (age at diagnosis and gender) and anatomic subsite (proximal, distal, rectum, or other). Multivariable Cox regression was used to assess the association between CRC-specific survival and nativity after adjusting for demographic characteristics, tumor characteristics (stage at diagnosis and anatomic subsite), and receipt of cancer-directed therapy (surgery and radiation).

Results: Fifty eight percent of cases of invasive CRC among Hispanics were diagnosed at a late stage and 63% of cases were among foreign-born individuals. Foreign-born Hispanics were significantly more likely than U.S.-born Hispanics to have a late-stage diagnosis after adjusting for demographic characteristics (adjusted odds ratio=1.08, p&lt;0.001). However, the demographics-adjusted mortality hazard was similar among foreign- and U.S.-born Hispanics (adjusted hazard ratio [AHR]=0.99, p-value=0.790). After adjusting for tumor characteristics, foreign-born Hispanics had improved survival compared to their U.S.-born counterparts (AHR=0.94, p=0.005). Their survival advantage remained significant after adjusting for both tumor characteristics and cancer-directed therapy (AHR=0.92, p&lt;0.001).

Conclusions: The increased prevalence of late-stage diagnosis among foreign-born Hispanics is likely a reflection of their reduced screening rates relative to Hispanics born in the U.S. However, the increased risk of late-stage diagnosis did not result in an increased mortality hazard among foreign-born Hispanics. In fact, survival was better among foreign- versus U.S.-born Hispanics after adjusting for stage at diagnosis and receipt of cancer-directed therapy. Similar patterns have been found for cervix and overall cancer survival and may be attributed to changes in risk profiles associated with acculturation (e.g., higher rates of smoking, obesity, alcohol consumption, and poor nutrition). Additionally, U.S.-born Hispanics have a higher prevalence of chronic diseases (e.g., diabetes, obesity, heart disease) that may negatively affect cancer survival. Our results suggest that the overlap between race/ethnicity and nativity status should not be overlooked in cancer health disparities research.

Citation Format: Jane R. Montealegre, Renke Zhou, E. Susan Amirian, Michael E. Scheurer. Colorectal cancer among Hispanics in the U.S.: Nativity disparities in stage at diagnosis and survival. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr C90. doi:10.1158/1538-7755.DISP13-C90

Abstract 4163: Chemokine and cytokine levels among lung cancer cases responsive to HPV antigen stimulation

Purpose: Human papillomavirus (HPV), the causative agent for anogenital and certain head and neck cancers, has been detected in lung tumors, but its role as an etiologic agent for lung cancer remains controversial. The lung is often subjected to exogenous inflammatory insults, and patients with chronic lung inflammation have an increased risk for cancer. In addition to the genomic instability that can be caused by HPV oncoproteins, the immunomodulatory impacts of HPV infection may foster a pro-inflammatory state that increases lung cancer risk. We sought to identify such immunomodulatory effects by examining the differences in lymphocyte and cytokine/chemokine profiles between lung cancer cases and HPV-vaccinated healthy controls.

Methods: Peripheral blood mononuclear cells were isolated from 22 newly diagnosed lung cancer cases and 11 healthy controls who had prior exposure to HPV antigens (immunized with Gardasil). Cells were enumerated via a hemacytometer, and were exposed to media alone or to 3 doses of Gardasil for 20 hours as an HPV challenge. Interleukin (IL-) 4, IFN-γ, and IL-17A secreting cells were then quantified using enzyme linked immunocell spot (ELISpot) analysis. Individuals were categorized as HPV-responsive if the HPV challenge resulted in an increase in at least 2 types of secreting cells, compared to media-exposed cells. The Milliplex human cytokine detection kit was used to assess circulating levels of 38 key cytokines in the plasma of cases and controls. Cytokine levels among HPV-responsive and HPV-non-responsive cases were compared. Survival analysis was also conducted.

Results: All 11 HPV-vaccinated controls demonstrated an increase in cells secreting IFN-γ and IL-4. Of the 22 cases, 13 (59%) were classified as HPV-responsive, with 2 cases displaying an increase in IFN-γ and IL-4 secreting cells upon HPV challenge. Levels of TGF-α, IL-10, IL-3, IL-5, and IL-7 were significantly higher among HPV-responsive compared to non-responsive cases. Significant survival differences were also observed by HPV-responsiveness and cytokine levels.

Conclusions: HPV clearly has substantial effects on the host's systemic immune response. Our study may explain whether and how the pathogenic process differs between HPV-infected and -uninfected lung tumors.

Citation Format: Michael E. Scheurer, E Susan Amirian, Paul Porter, David B. Corry. Chemokine and cytokine levels among lung cancer cases responsive to HPV antigen stimulation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4163. doi:10.1158/1538-7445.AM2014-4163

Age patterns of Kaposi's sarcoma incidence in a cohort of HIV-infected men

The life expectancy for HIV-positive individuals has improved over time due to increasing access to highly active antiretroviral therapy (HAART). Yet, as the HIV-positive population ages, their risk of developing cancers also increases. Studies of Kaposi's sarcoma (KS) among elderly HIV-infected persons are quite limited. We examined the age patterns of KS incidence and an association between age and KS risk in a US cohort of 3458 HIV-infected men, the Multicenter AIDS Cohort Study (MACS). Poisson distribution was used to calculate incidence rates and respective 95% confidence intervals (95% CIs). Cox proportional hazards regression was performed to examine the association between age and KS risk. There were 534 incident KS cases with a total follow-up time of 25,134 person-years. The overall KS incidence rate was 2.13 per 100 person-years (95% CI: 1.95–2.32) (Non-HAART users-ever: 5.57 per 100 person-years [95% CI: 5.09–6.10]; HAART users-ever: 0.39 per 100 person-years [95% CI: 0.31–0.51]). Overall, KS frequency and incidence declined with age, even in the oldest age group (p_trend < 0.0001). However, among non-HAART users-ever, the oldest age group had the highest incidence rate ratio compared to younger individuals [15.01, 95% CI: 6.12–44.22]). While the incidence of KS decreased with age, older HIV-infected persons who do not receive HAART are still at increased risk of KS. As KS remains an important malignancy among HIV-infected persons, earlier HIV diagnoses and HAART initiation, particularly in older HIV-infected persons is warranted.

Uncovering nativity disparities in cancer patterns: Multiple imputation strategy to handle missing nativity data in the Surveillance, Epidemiology, and End Results data file

BACKGROUND

Although birthplace data are routinely collected in the participating Surveillance, Epidemiology, and End Results (SEER) registries, such data are missing in a nonrandom manner for a large percentage of cases. This hinders analysis of nativity-related cancer disparities. In the current study, the authors evaluated multiple imputation of nativity status among Hispanic patients diagnosed with cervical, prostate, and colorectal cancer and demonstrated the effect of multiple imputation on apparent nativity disparities in survival.

METHODS

Multiple imputation by logistic regression was used to generate nativity values (US-born vs foreign-born) using a priori-defined variables. The accuracy of the method was evaluated among a subset of cases. Kaplan-Meier curves were used to illustrate the effect of imputation by comparing survival among US-born and foreign-born Hispanics, with and without imputation of nativity.

RESULTS

Birthplace was missing for 31%, 49%, and 39%, respectively, of cases of cervical, prostate, and colorectal cancer. The sensitivity of the imputation strategy for detecting foreign-born status was ≥90% and the specificity was ≥86%. The agreement between the true and imputed values was ≥0.80 and the misclassification error was ≤10%. Kaplan-Meier survival curves indicated different associations between nativity and survival when nativity was imputed versus when cases with missing birthplace were omitted from the analysis.

CONCLUSIONS

Multiple imputation using variables available in the SEER data file can be used to accurately detect foreign-born status. This simple strategy may help researchers to disaggregate analyses by nativity and uncover important nativity disparities in regard to cancer diagnosis, treatment, and survival.

Clinical implications of the cervical Papanicolaou test results in the management of anal warts in HIV-infected women

The Papanicolaou test (or Pap test) has long been used as a screening tool to detect cervical precancerous/cancerous lesions. However, studies on the use of this test to predict both the presence and change in size of genital warts are limited. We examined whether cervical Papanicolaou test results are associated with the size of the largest anal wart over time in HIV-infected women in an on-going cohort study in the US. A sample of 976 HIV-infected women included in a public dataset obtained from the Women’s Interagency HIV Study (WIHS) was selected for analysis. A linear mixed model was performed to determine the relationship between the size of anal warts and cervical Pap test results. About 32% of participants had abnormal cervical Pap test results at baseline. In the adjusted model, a woman with a result of Atypia Squamous Cell Undetermined Significance/Low-grade Squamous Intraepithelial Lesion (ASCUS/LSIL) had an anal wart, on average, 12.81 mm² larger than a woman with normal cervical cytology. The growth rate of the largest anal wart after each visit in a woman with ASCUS/LSIL was 1.56 mm² slower than that of a woman with normal cervical results. However, they were not significant (P = 0.54 and P = 0.82, respectively). This is the first study to examine the relationship between cervical Pap test results and anal wart development in HIV-infected women. Even though no association between the size of anal wart and cervical Pap test results was found, a screening program using anal cytology testing in HIV-infected women should be considered. Further studies in cost-effectiveness and efficacy of an anal cytology test screening program are warranted.

Potential role of gastrointestinal microbiota composition in prostate cancer risk

Background

Among men in the U.S., prostate cancer is the most common cancer and the second leading cause of cancer death. Despite its prevalence, there are few established risk factors for prostate cancer. Some studies have found that intake of certain foods/nutrients may be associated with prostate cancer risk, but few have accounted for how intake and metabolic factors may interact to influence bioavailable nutrient levels and subsequent disease risk.

Presentation of the hypothesis

The composition of the gastrointestinal (GI) microbiome may influence metabolism of dietary compounds and nutrients (e.g., plant phenols, calcium, choline) that may be relevant to prostate cancer risk. We, therefore, propose the hypothesis that GI microbiota may have a markedly different composition among individuals with higher prostate cancer risk. These individuals could have microbial profiles that are conducive to intestinal inflammation and/or are less favorable for the metabolism and uptake of chemopreventive agents.

Testing the hypothesis

Because very little preliminary data exist on this potential association, a case–control study may provide valuable information on this topic. Such a study could evaluate whether the GI microbial profile is markedly different between three groups of individuals: healthy men, those with latent prostate cancer, and those with invasive prostate cancer. Any findings could then be validated in a larger study, designed to collect a series of specimens over time.

Implications of the hypothesis

Given the plethora of information emerging from the Human Microbiome Project, this is an opportune time to explore associations between the microbiome and complex human diseases. Identification of profiles that alter the host’s risk for disease may clarify inconsistencies in the literature on dietary factors and cancer risk, and could provide valuable targets for novel cancer prevention strategies.

Nativity disparities in late-stage diagnosis and cause-specific survival among Hispanic women with invasive cervical cancer: an analysis of Surveillance, Epidemiology, and End Results data

PURPOSE

While cervical cancer screening and risk behaviors have been found to vary among US- and foreign-born Hispanic women, many cancer epidemiology studies have conceptualized Hispanics as a homogenous group. Here, we examine differences in cervical cancer stage at diagnosis and survival among Hispanic women by nativity.

METHODS

We use data from the Surveillance, Epidemiology, and End Results program, 1998-2008. Nativity was based on place of birth and was categorized as US versus foreign born. Distant and regional tumors were classified as late stage, while local tumors were classified as early stage.

RESULTS

Forty-seven percent of cases of invasive cervical cancer among Hispanics were diagnosed at a late stage, and over half of invasive cervical cancer cases were among foreign-born women. Foreign-born Hispanic women were significantly more likely than US-born Hispanics to have late-stage diagnosis, after adjusting for age at diagnosis and tumor histology (adjusted odds ration = 1.09, p value = 0.003). There was heterogeneity in the association between nativity and survival by stage at diagnosis. Among cases with early-stage diagnosis, survival was poorer among foreign-born versus US-born Hispanics after adjusting for age at diagnosis, histology, and cancer-directed therapy [adjusted hazard ratios (HR) = 1.31, p value = 0.030]. However, among cases with late-stage diagnosis, survival was better among foreign-born Hispanics (adjusted HR = 0.81, p value < 0.001).

CONCLUSIONS

We hypothesize that nativity differences in survival may be indicative of diverse risk, screening, and treatment profiles. Given such differences, it may be inappropriate to aggregate Hispanics as a single group for cervical cancer research.

The role of Hispanic ethnicity in pediatric Wilms' tumor survival

Wilms' tumors (WT) constitute approximately 6-14% of all childhood cancers and about 95% of all pediatric renal malignancies. While prognostic factors for this malignancy are relatively well-defined, few studies have specifically examined the role of Hispanic ethnicity in pediatric WT survival. The purpose of this study was to compare WT survival among non-Hispanic white (NHW), non-Hispanic black (NHB), and Hispanic cases using data from the Surveillance, Epidemiology, and End Results (SEER) program. WT cases (ICD-O-3 histological code 8960) under age 20 were isolated from a recent subset of the SEER dataset (1990-2009). Demographics and tumor characteristics were compared by race/ethnicity, and 5- and 10-year survival probabilities were calculated. Multivariable Cox proportional hazards regression was used to assess the effects of race/ethnicity on WT survival, adjusting for relevant covariates. Hispanic ethnicity was significantly associated with WT-specific mortality hazard, controlling for age, sex, diagnosis/treatment era, laterality, SEER stage, cancer-directed surgery, and radiation therapy (HR: 1.52, 95% CI: 1.02-2.25). The results of this study suggest that Hispanic pediatric WT cases may have a higher risk of WT-related death, compared to NHW cases. Additional research on racial/ethnic disparities in WT survival is warranted.

Associations between human herpesvirus-6, human papillomavirus and cervical cancer

Cervical cancer (CxCa) is the second most common cancer among women globally. Human papillomavirus (HPV) infection is thought to be a necessary, but not sufficient, causal factor in CxCa development. Why some women are able to clear HPV infection with no adverse effects, whereas others develop cancer, remains unclear. HHV-6 has demonstrated transformative abilities and has been shown to be present in the genital tract. However, based on the current evidence, we cannot conclude that HHV-6 is a co-factor in HPV-associated carcinogenesis. Nonetheless, future research is warranted because of several crucial gaps in the literature.

The interaction between smoking status and highly active antiretroviral therapy (HAART) use on the risk of Kaposi's sarcoma (KS) in a cohort of HIV-infected men

Background:

Although the independent effects of smoking status and HAART are reported as lower risks against KS, their combined effects have not been explored. We examined whether there is an interaction between smoking status and HAART use on the risk of KS development in an on-going US cohort of HIV-infected men.

Methods:

Cox proportional hazards regression was used to analyse a total sample of 2736 participants of the Multicenter AIDS Cohort Study (MACS).

Results:

We identified 530 incident KS cases with a total follow-up time of 26 594 person-years (incidence rate: 2.00 out of 100 person-years). Current smoking status and HAART use were independently associated with a lower risk of KS development (hazard ratio – HR=0.56, 95% CI: 0.35–0.90, P=0.02 and HR=0.27, 95% CI: 0.16–0.48, P<0.0001, respectively). There was no evidence of multiplicative interaction between current smoking status and HAART use on KS risk (HR=2.14, 95% CI: 0.97–4.73, P_interaction=0.06). Lower effect of smoking was only present among those not on HAART (HR=0.57, 95% CI: 0.35–0.92, P=0.02).

Conclusion:

The inverse association of cigarette smoking on KS risk may be limited to those not on HAART. The biological mechanism of smoking in KS carcinogenesis should be elucidated.

Anti-human-cytomegalovirus immunoglobulin G levels in glioma risk and prognosis

The role of human cytomegalovirus (HCMV) in glioma development and progression remains controversial. The purpose of our study was to assess the potential associations between anti-HCMV antibodies (immunoglobulin G [IgG] and immunoglobulin M [IgM]) and glioma risk and prognosis using data from the Harris County Case–Control Study. Multivariable logistic regression models were utilized to estimate odds ratios and 95% confidence intervals (CI) for the associations between glioma status and antibody levels among glioma cases (n = 362) and cancer-free controls (n = 462). Hazard ratios and 95% CIs were calculated using Cox proportional hazards regression, adjusting for age, race, and sex, to determine if antibody levels were associated with survival over time among cases. Among IgG-positive participants, increasing anti-HCMV IgG levels were associated with decreasing glioma risk (P for trend = 0.0008), and those with the lowest level of anti-HCMV IgG (<10 U/mL) had the highest glioma risk, controlling for age, sex, and race/ethnicity (OR: 2.51, 95% CI: 1.42–4.43). Antibody levels were not associated with survival among glioma cases. Our study contributes new evidence toward the potential importance of the direct and indirect effects of HCMV infection in gliomagenesis.