Long-term exposure to ambient fine particulate matter and risk of liver cancer in the NIH-AARP Diet and Health Study

BACKGROUND

Fine particulate matter (PM2.5) exposure has been associated with liver cancer incidence and mortality in a limited number of studies. We sought to evaluate this relationship for the first time in a U.S. cohort with historical exposure assessment.

METHODS

We used spatiotemporal prediction models to estimate annual average historical PM2.5 concentrations (1980-2015) at residential addresses of 499,729 participants in the NIH-AARP Diet and Health Study, a cohort in 6 states (California, Florida, Louisiana, New Jersey, North Carolina, and Pennsylvania) and 2 metropolitan areas (Atlanta, Georgia, and Detroit, Michigan) enrolled in 1995-1996 and followed up through 2017. We used a time-varying Cox model to estimate the association for liver cancer and the predominant histologic type, hepatocellular carcinoma (HCC), per 5 µg/m3 increase in estimated outdoor PM2.5 levels, incorporating a 5-year average, lagged 10 years prior to cancer diagnosis and adjusting for age, sex, race/ethnicity, education level and catchment state. We also evaluated PM2.5 interactions with hypothesized effect modifiers.

RESULTS

We observed a non-significantly increased risk of liver cancer associated with estimated PM2.5 exposure (Hazard ratio [HR] = 1.05 [0.96-1.14], N = 1,625); associations were slightly stronger for HCC, (84 % of cases; HR = 1.08 [0.98-1.18]). Participants aged 70 or older at enrollment had an increased risk of liver cancer versus other age groups (HR = 1.50 [1.01-2.23]); p-interaction = 0.01) and risk was elevated among participants who did not exercise (HR = 1.81 [1.22-2.70]; p-interaction = 0.01). We found no evidence of effect modification by sex, smoking status, body mass index, diabetes status, or alcohol consumption (p-interaction > 0.05).

CONCLUSIONS

Our findings in this large cohort suggest that residential ambient PM2.5 levels may be associated with liver cancer risk. Further exploration of the variation in associations by age and physical activity are important areas for future research.

Prediagnostic serum concentrations of per- and polyfluoroalkyl substances and risk of papillary thyroid cancer in the Finnish Maternity Cohort

Human exposure to per- and polyfluoroalkyl substances (PFAS) occurs globally through contaminated food, dust, and drinking water. Studies of PFAS and thyroid cancer have been limited. We conducted a nested case-control study of prediagnostic serum levels of 19 PFAS and papillary thyroid cancer (400 cases, 400 controls) in the Finnish Maternity Cohort (pregnancies 1986-2010; follow-up through 2016), individually matched on sample year and age. We used conditional logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI) for log2 transformed and categorical exposures, overall and stratified by calendar period, birth cohort, and median age at diagnosis. We adjusted for other PFAS with Spearman correlation rho = 0.3-0.6. Seven PFAS, including perfluoroctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), N-ethyl-perfluorooctane sulfonamidoacetic acid (EtFOSAA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluorohexane sulfonic acid (PFHxS) were detected in >50% of women. These PFAS were not associated with risk of thyroid cancer, except for PFHxS, which was inversely associated (OR log2  = 0.82, 95% CI: 0.70-0.97). We observed suggestive but imprecise increased risks associated with PFOA, PFOS, and EtFOSAA for those diagnosed at ages <40 years, whereas associations were null or inverse among those diagnosed at 40+ years (P-interaction: .02, .08, .13, respectively). There was little evidence of other interactions. These results show no clear association between PFAS and papillary thyroid cancer risk. Future work would benefit from evaluation of these relationships among those with higher exposure levels and during periods of early development when the thyroid gland may be more susceptible to environmental harms.

Fiber and whole grain intakes in relation to liver cancer risk: An analysis in 2 prospective cohorts and systematic review and meta-analysis of prospective studies

BACKGROUND AND AIMS

The association between fiber or whole grain intakes and the risk of liver cancer remains unclear. We assessed the associations between fiber or whole grain intakes and liver cancer risk among 2 prospective studies, and systematically reviewed and meta-analyzed these results with published prospective studies.

APPROACH AND RESULTS

A total of 111,396 participants from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) and 26,085 men from the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study were included. Intakes of total fiber and whole grains were estimated from validated food frequency questionnaires. Study-specific HRs and 95% CI with liver cancer risk were estimated using multivariable-adjusted Cox regression. We systematically reviewed existing literature, and studies were combined in a dose-response meta-analysis. A total of 277 (median follow-up = 15.6 y) and 165 (median follow-up = 16.0 y) cases of liver cancer were observed in Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial and Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, respectively. Dietary fiber was inversely associated with liver cancer risk in Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (HR 10g/day : 0.69; 95% CI: 0.55-0.86). No significant associations were observed between whole grain intakes and liver cancer risk in either study. Our meta-analysis included 2383 incident liver cancer cases (7 prospective cohorts) for fiber intake and 1523 cases (5 prospective cohorts) for whole grain intake; combined HRs for liver cancer risk were 0.83 (0.76-0.91) per 10 g/day of fiber and 0.92 (0.85-0.99) per 16 g/day (1 serving) of whole grains.

CONCLUSIONS

Dietary fiber and whole grains were inversely associated with liver cancer risk. Further research exploring potential mechanisms and different fiber types is needed.

Incidence of Etiology-specific Hepatocellular Carcinoma: Diverging Trends and Significant Heterogeneity by Race and Ethnicity

BACKGROUND & AIMS

The main causes of hepatocellular carcinoma (HCC) include chronic hepatitis C and B viral infections (HCV, HBV), nonalcoholic fatty liver disease (NAFLD), and alcohol-related disease (ALD). Etiology-specific HCC incidence rates and temporal trends on a population-basis are needed to improve HCC control and prevention.

METHODS

All 14,420 HCC cases from the Florida statewide cancer registry were individually linked to data from the hospital discharge agency and the viral hepatitis department to determine the predominant etiology of each case diagnosed during 2010 to 2018. Age-adjusted incidence rates (AAIRs) were used to assess the intersection between etiology and detailed race-ethnicity. Etiology-specific temporal trends based on diagnosis year were assessed using Joinpoint regression.

RESULTS

HCV remains the leading cause of HCC among men, but since 2017 NAFLD-HCC is the leading cause among women. HCV-HCC AAIRs are particularly high among U.S.-born minority men, including Puerto Rican (10.9 per 100,000), African American (8.0 per 100,000), and U.S.-born Mexican American men (7.6 per 100,000). NAFLD is more common among all Hispanics and Filipinos and HBV-HCC among Asian and Haitian black men. HCV-HCC surpasses HBV-HCC in Asian women. ALD-HCC is high among specific Hispanic male groups. Population-based HCV-HCC rates experienced a rapid decline since 2015 (-9.6% annually), whereas ALD-HCC (+6.0%) and NAFLD-HCC (+4.3%) are rising (P < .05).

CONCLUSIONS

New direct acting anti-viral drugs have impacted rates of HCV-HCC, offsetting important increases in both ALD- and NAFLD-HCC. Hispanics may be a group of concern because of higher rates for ALD- and NAFLD-HCC. HCC etiology varies remarkably and may warrant specific interventions by detailed race-ethnicity.

Identification of pre-diagnostic lipid sets associated with liver cancer risk using untargeted lipidomics and chemical set analysis: A nested case-control study within the ATBC cohort

In pre-disposed individuals, a reprogramming of the hepatic lipid metabolism may support liver cancer initiation. We conducted a high-resolution mass spectrometry based untargeted lipidomics analysis of pre-diagnostic serum samples from a nested case-control study (219 liver cancer cases and 219 controls) within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study. Out of 462 annotated lipids, 158 (34.2%) were associated with liver cancer risk in a conditional logistic regression analysis at a false discovery rate (FDR) <0.05. A chemical set enrichment analysis (ChemRICH) and co-regulatory set analysis suggested that 22/28 lipid classes and 47/83 correlation modules were significantly associated with liver cancer risk (FDR <0.05). Strong positive associations were observed for monounsaturated fatty acids (MUFA), triacylglycerols (TAGs) and phosphatidylcholines (PCs) having MUFA acyl chains. Negative associations were observed for sphingolipids (ceramides and sphingomyelins), lysophosphatidylcholines, cholesterol esters and polyunsaturated fatty acids (PUFA) containing TAGs and PCs. Stearoyl-CoA desaturase enzyme 1 (SCD1), a rate limiting enzyme in fatty acid metabolism and ceramidases seems to be critical in this reprogramming. In conclusion, our study reports pre-diagnostic lipid changes that provide novel insights into hepatic lipid metabolism reprogramming may contribute to a pro-cell growth and anti-apoptotic tissue environment and, in turn, support liver cancer initiation.

Cancer incidence in the US military: An updated analysis

BACKGROUND

Military and general populations differ in factors related to cancer occurrence and diagnosis. This study compared incidence of colorectal, lung, prostate, testicular, breast, and cervical cancers between the US military and general US populations.

METHODS

Data from the US Department of Defense's Automated Central Tumor Registry (ACTUR) and the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program were analyzed. Persons in ACTUR were active-duty members 20-59 years old during 1990-013. The same criteria applied to persons in SEER. Age-adjusted incidence rates, incidence rate ratios, and 95% confidence intervals were calculated by sex, race, age, and cancer stage. Temporal trends were analyzed.

RESULTS

ACTUR had higher rates of prostate and breast cancers, particularly in 40- to 59-year-olds. Further analyses by tumor stage showed this was primarily confined to localized stage. Incidence rates of colorectal, lung, testicular, and cervical cancers were significantly lower in ACTUR than in SEER, primarily for regional and distant tumors in men. Temporal incidence trends were generally similar overall and by stage between the populations, although distant colorectal cancer incidence tended to decrease starting in 2006 in ACTUR whereas it increased during the same period in SEER.

CONCLUSION

Higher rates of breast and prostate cancers in servicemembers 40-59 years of age than in the general population may result from greater cancer screening utilization or cumulative military exposures. Lower incidence of other cancers in servicemembers may be associated with better health status.

Trends in hepatocellular carcinoma stage by racial/ethnic group in the United States, 1992-2019

Background & Aims

Although incidence rates of hepatocellular carcinoma (HCC) began to decline in the United States in the past decade, disparities in rates among racial/ethnic groups have persisted. Whether disparities in stage at diagnosis have remained over time, however, is unclear.

Methods

National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program has created a new staging-over-time variable that facilitates the examination of trends in HCC stage. Thus, the proportions of HCCs diagnosed by stage between 1992 and 2019 were examined among non-Hispanic White, non-Hispanic Black (NHB), Hispanic, Asian/Pacific Islander, and American Indian/Alaska Native (AI/AN) individuals. HCC incidence between 1992 and 2019 was also analysed using Joinpoint regression.

Results

Between 1992 and 2019, the proportion of stage 1 HCCs increased and the proportion of stage 4 HCCs decreased among non-Hispanic White, NHB, Hispanic, and Asian/Pacific Islander individuals. Among AI/AN persons, the proportion of stage 1 tumours remained stable, and the proportion of stage 4 tumours declined. In the most recent time period, NHB individuals had the lowest proportions of stage 1 HCCs (32%) and the highest proportion of stage 4 HCCs (20%) of any group. Joinpoint analysis found that HCC incidence began to decline by 2013 among all groups except AI/AN individuals, the only group that had an increase in incidence.

Conclusions

Despite generally favourable trends in HCC stage and incidence rates, disparities remain. NHB persons continue to have less favourable stages at diagnosis, and incidence rates continue to increase among AI/AN persons.

Impact and implications

HCC incidence rates among most United States racial/ethnic groups began to decline in recent years, but whether stage at diagnosis also improved was unclear. As a result, a new SEER stage variable was used to examine stage trends by race/ethnicity. Although the finding of generally favourable trends in stage as well as incidence is encouraging, continuity disparities in both stage and incidence require serious attention.

Prediagnostic Hormone Levels and Risk of Testicular Germ Cell Tumors: A Nested Case-Control Study in the Janus Serum Bank

BACKGROUND

It has been hypothesized that poorly functioning Leydig and/or Sertoli cells of the testes, indicated by higher levels of serum gonadotropins and lower levels of androgens, are related to the development of testicular germ cell tumors (TGCT). To investigate this hypothesis, we conducted a nested case-control study within the Janus Serum Bank cohort.

METHODS

Men who developed TGCT (n = 182) were matched to men who did not (n = 364). Sex steroid hormones were measured using LC/MS. Sex hormone binding globulin, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were quantified by direct immunoassay. Multivariable logistic regression was used to calculate ORs and 95% confidence intervals (CI) for associations between hormone levels and TGCT risk.

RESULTS

Higher FSH levels [tertile (T) 3 vs. T2: OR = 2.89, 95% CI = 1.83-4.57] were associated with TGCT risk, but higher LH levels were not (OR = 1.26, 95% CI = 0.81-1.96). The only sex steroid hormone associated with risk was androstane-3α, 17β-diol-3G (3α-diol-3G; OR = 2.37, 95% CI = 1.46-3.83). Analysis by histology found that increased FSH levels were related to seminoma (OR = 3.55, 95% CI = 2.12-5.95) but not nonseminoma (OR = 1.19, 95% CI = 0.38-3.13). Increased levels of 3α-diol-3G were related to seminoma (OR = 2.29, 95% CI = 1.35-3.89) and nonsignificantly related to nonseminoma (OR = 2.71, 95% CI = 0.82-8.92).

CONCLUSIONS

Higher FSH levels are consistent with the hypothesis that poorly functioning Sertoli cells are related to the development of TGCT. In contrast, higher levels of 3α-diol-3G do not support the hypothesis that insufficient androgenicity is related to risk of TGCT.

IMPACT

Clarifying the role of sex hormones in the development of TGCT may stimulate new research hypotheses.

Testicular cancer mortality in Latin America and the Caribbean: trend analysis from 1997 to 2019

BACKGROUND

In the last decades, an increasing incidence of testicular cancer has been observed in several countries worldwide. Although mortality rates have been variable in many countries, little information is available from Latin America and the Caribbean (LAC). Therefore, we examined mortality trends of testicular cancer in the last two decades.

METHODS

Age-standardized mortality rates (ASMR) of testicular cancer per 100,000 men-years were estimated using the World Health Organization mortality database from 1997 to 2019. We examined the mortality trends and computed annual percent change (APC) for all ages and the following age groups, 15-29, 30-44, 15-44, and ≥ 45 years.

RESULTS

Ten countries had mortality rates greater than 0.43 per 100,000 men, with the highest rates for Chile, Mexico, and Argentina. Significant increases in mortality rates were observed in Argentina, Brazil Colombia, and Mexico in all ages, and < 45 years, while Colombia, Ecuador, Mexico, and Peru reported significant downward trends in males aged ≥ 45 years. Only Chile showed significant decreases for all ages and age groups studied.

CONCLUSION

Mortality by testicular cancer increased among LAC countries in males of all ages and across age groups. A reduction in mortality rates was observed only in Chilean males of all ages and in men ≥ 45 years in several countries. Strengthening of early detection among symptomatic males may decrease the mortality by this neoplasm.

Daytime napping, nighttime sleeping duration, and risk of hepatocellular carcinoma and liver disease-related mortality

Background & Aims

Sleep duration has been linked to metabolic dysfunction and chronic inflammation, which may contribute to the development of liver cancer and chronic liver disease (CLD). However, little is known about the relationship between sleep or napping duration and hepatocellular carcinoma (HCC) risk and CLD mortality.

Methods

We followed 295,837 individuals in the National Institutes of Health-American Association of Retired Persons (NIH-AARP) Diet and Health Study. We examined the associations of nighttime sleep duration and daytime napping duration with risk of HCC incidence and CLD mortality. Cox proportional hazards regression was used to calculate multivariable hazard ratios (HRs) and 95% confidence intervals (95% CIs).

Results

A total of 357 incident HCC cases and 578 CLD deaths were identified after a median follow-up time of 15.5 years. After adjusting for confounder factors, we found U-shaped associations of nighttime sleep duration with the incidence of HCC (HR<5 vs. 7-8 h = 2.00, 95% CI: 1.22-3.26 and HR≥9 vs. 7-8 h = 1.63, 95% CI: 1.04-2.65) and CLD mortality (HR<5 vs. 7-8 h = 1.78, 95% CI: 1.18-2.69 and HR≥9 vs. 7-8 h = 1.91, 95% CI: 1.35-2.70). Daytime napping was associated with higher risk of HCC (HR≥1 vs. non-nappers = 1.46, 95% CI: 1.04-2.06) and higher CLD mortality (HR≥1 h vs. non-nappers = 1.54, 95% CI: 1.18-2.01) compared with no napping.

Conclusions

We observed U-shaped associations for nighttime sleeping and risk of HCC and CLD mortality. Additionally, longer daytime napping duration was associated with higher risk of HCC and CLD death. Our study suggests that clinical follow up of individuals at risk for liver cancer or living with a liver disease should include information on nighttime and daytime sleep.

Impact and implications

Sleep or napping duration may play a role in the development of liver cancer and chronic liver disease, but little is known about the relationship between them. In addition, abnormal sleep patterns in patients with chronic liver disease may further promote the development of liver disease, creating a vicious cycle. Our study suggests that clinical follow up of individuals at risk for liver cancer or living with a liver disease should include information on nighttime and daytime sleep, as they can be potentially important factors in the development and progression of liver disease.

Sugar-Sweetened and Artificially Sweetened Beverages and Risk of Liver Cancer and Chronic Liver Disease Mortality

Importance

Approximately 65% of adults in the US consume sugar-sweetened beverages daily.

Objective

To study the associations between intake of sugar-sweetened beverages, artificially sweetened beverages, and incidence of liver cancer and chronic liver disease mortality.

Design, Setting, and Participants

A prospective cohort with 98 786 postmenopausal women aged 50 to 79 years enrolled in the Women's Health Initiative from 1993 to 1998 at 40 clinical centers in the US and were followed up to March 1, 2020.

Exposures

Sugar-sweetened beverage intake was assessed based on a food frequency questionnaire administered at baseline and defined as the sum of regular soft drinks and fruit drinks (not including fruit juice); artificially sweetened beverage intake was measured at 3-year follow-up.

Main Outcomes and Measures

The primary outcomes were (1) liver cancer incidence, and (2) mortality due to chronic liver disease, defined as death from nonalcoholic fatty liver disease, liver fibrosis, cirrhosis, alcoholic liver diseases, and chronic hepatitis. Cox proportional hazards regression models were used to estimate multivariable hazard ratios (HRs) and 95% CIs for liver cancer incidence and for chronic liver disease mortality, adjusting for potential confounders including demographics and lifestyle factors.

Results

During a median follow-up of 20.9 years, 207 women developed liver cancer and 148 died from chronic liver disease. At baseline, 6.8% of women consumed 1 or more sugar-sweetened beverage servings per day, and 13.1% consumed 1 or more artificially sweetened beverage servings per day at 3-year follow-up. Compared with intake of 3 or fewer servings of sugar-sweetened beverages per month, those who consumed 1 or more servings per day had a significantly higher risk of liver cancer (18.0 vs 10.3 per 100 000 person-years [P value for trend = .02]; adjusted HR, 1.85 [95% CI, 1.16-2.96]; P = .01) and chronic liver disease mortality (17.7 vs 7.1 per 100 000 person-years [P value for trend <.001]; adjusted HR, 1.68 [95% CI, 1.03-2.75]; P = .04). Compared with intake of 3 or fewer artificially sweetened beverages per month, individuals who consumed 1 or more artificially sweetened beverages per day did not have significantly increased incidence of liver cancer (11.8 vs 10.2 per 100 000 person-years [P value for trend = .70]; adjusted HR, 1.17 [95% CI, 0.70-1.94]; P = .55) or chronic liver disease mortality (7.1 vs 5.3 per 100 000 person-years [P value for trend = .32]; adjusted HR, 0.95 [95% CI, 0.49-1.84]; P = .88).

Conclusions and Relevance

In postmenopausal women, compared with consuming 3 or fewer servings of sugar-sweetened beverages per month, those who consumed 1 or more sugar-sweetened beverages per day had a higher incidence of liver cancer and death from chronic liver disease. Future studies should confirm these findings and identify the biological pathways of these associations.

Aflatoxin exposure in adults in southern and eastern Mexico in 2018: A descriptive study

OBJECTIVE

To estimate the frequency of detection and levels of aflatoxin B1-lysine adduct (AFB1-lys), an important hepatocellular carcinoma (HCC) risk factor, in eastern and southern Mexico.

MATERIALS AND METHODS

We determined serum AFB1-lys using mass spectrometry in a representative sample of 952 adults (weighted n = 7,493,354) from five states (Campeche, Chiapas, Tamaulipas, Veracruz and Yucatán) in 2018. We calculated overall and subgroup-specific frequency of detection and 95% confidence intervals (95%CI) and median AFB1-lys levels and quartiles.

RESULTS

The overall frequency of detection of AFB1-lys was 91.9% (95%CI 88.6, 94.3). The median AFB1-lys level was 0.172 pg/μL (Q1-Q3, 0.060-0.582). Levels differed geographically (median pg/μL, 0.361 for Veracruz and 0.061 for Yucatan) and were higher among men and older individuals. Levels were almost three times higher in rural relative to urban areas (0.317 vs. 0.123 pg/μL). We observed higher AFB1-lys exposure in lower socioeconomic status (SES) level populations.

CONCLUSION

AFB1-lys frequency of detection was very high and exposure levels were highest in Veracruz, men, rural areas, and among persons of lower SES. Understanding modifiable HCC risk factors in populations with unique epidemiological patterns could inform preventative interventions.

MilCanEpi: Increased Capability for Cancer Care Research in the Department of Defense

The Military Health System (MHS) of the US Department of Defense (DoD) provides comprehensive medical care to over nine million beneficiaries, including active-duty members, reservists, activated National Guard, military retirees, and their family members. The MHS generates an extensive database containing administrative claims and medical encounter data, while the DoD also maintains a cancer registry that collects information about the occurrence of cancer among its beneficiaries who receive care at military treatment facilities. Collating data from the two sources diminishes the limitations of using registry or medical claims data alone for cancer research and extends their usage. To facilitate cancer research using the unique military health resources, a computer interface linking the two databases has been developed, called Military Cancer Epidemiology, or MilCanEpi. The intent of this article is to provide an overview of the MilCanEpi data system, describing its components, structure, potential uses, and limitations.

Hispanic Individuals are Underrepresented in Phase III Clinical Trials for Advanced Liver Cancer in the United States

Background

Hispanic individuals comprise the second-largest subpopulation after non-Hispanic White (NHW) individuals in the United States (US). We compared the relative contribution of Hispanic individuals to the ten most common causes of cancer-related deaths and studied enrollment of Hispanic patients in multinational phase III advanced liver cancer trials with the aim to investigate whether racial subpopulations are adequately represented in liver cancer trials.

Methods

Relative cancer incidence rates in Hispanic individuals, NHW individuals, non-Hispanic black (NHB) individuals, and Asian individuals were obtained from both the National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results Program and the Center for Disease Control and Prevention (CDC), United States Cancer Statistics (USCS) database. Searching PubMed, Embase, and Web of Science, we identified phase III clinical trials studying advanced liver cancer in the last ten years and collected enrollment for each race and ethnicity. Incidence rates of liver cancer and enrollment rates in phase III trials were compared by race and ethnicity.

Results

The cancer type with the relatively highest contribution of Hispanic individuals was liver cancer. From 2015 to 2019, 15.1% of liver cancer cases occurred in Hispanic individuals compared to 12.5% in Asian individuals, 11% in NHB individuals, and 7.5% in NHW individuals. In the last ten years, Hispanic individuals made up 1.6% of patients and NHB individuals 1.3% of patients included in phase III multinational liver cancer trials, compared to 31% NHW individuals and 47% Asian individuals.

Conclusion

Hispanic individuals are disproportionately underrepresented in multinational phase III clinical trials for liver cancer despite having the highest relative incidence rates among the four major racial or ethnic groups in the US.

Endogenous sex steroid hormones and risk of liver cancer among US men: Results from the Liver Cancer Pooling Project

Background & Aims

Incidence rates of liver cancer in most populations are two to three times higher among men than women. The higher rates among men have led to the suggestion that androgens are related to increased risk whereas oestrogens are related to decreased risk. This hypothesis was investigated in the present study via a nested case-control analysis of pre-diagnostic sex steroid hormone levels among men in five US cohorts.

Methods

Concentrations of sex steroid hormones and sex hormone-binding globulin were quantitated using gas chromatography-mass spectrometry and a competitive electrochemiluminescence immunoassay, respectively. Multivariable conditional logistic regression was used to calculate odds ratios (ORs) and 95% CIs for associations between hormones and liver cancer among 275 men who subsequently developed liver cancer and 768 comparison men.

Results

Higher concentrations of total testosterone (OR per one-unit increase in log₂ = 1.77, 95% CI = 1.38-2.29), dihydrotestosterone (OR = 1.76, 95% CI = 1.21-2.57), oestrone (OR = 1.74, 95% CI = 1.08-2.79), total oestradiol (OR = 1.58, 95% CI=1.22-20.05), and sex hormone-binding globulin (OR = 1.63, 95% CI = 1.27-2.11) were associated with increased risk. Higher concentrations of dehydroepiandrosterone (DHEA), however, were associated with a 53% decreased risk (OR = 0.47, 95% CI = 0.33-0.68).

Conclusions

Higher concentrations of both androgens (testosterone, dihydrotestosterone) and their aromatised oestrogenic metabolites (oestrone, oestradiol) were observed among men who subsequently developed liver cancer compared with men who did not. As DHEA is an adrenal precursor of both androgens and oestrogens, these results may suggest that a lower capacity to convert DHEA to androgens, and their subsequent conversion to oestrogens, confers a lower risk of liver cancer, whereas a greater capacity to convert DHEA confers a greater risk.

Impact and implications

This study does not fully support the current hormone hypothesis as both androgen and oestrogen levels were associated with increased risk of liver cancer among men. The study also found that higher DHEA levels were associated with lower risk, thus suggesting the hypothesis that greater capacity to convert DHEA could be associated with increased liver cancer risk among men.

Genome-wide Association Study of Bladder Cancer Reveals New Biological and Translational Insights

BACKGROUND

Genomic regions identified by genome-wide association studies (GWAS) for bladder cancer risk provide new insights into etiology.

OBJECTIVE

To identify new susceptibility variants for bladder cancer in a meta-analysis of new and existing genome-wide genotype data.

DESIGN, SETTING, AND PARTICIPANTS

Data from 32 studies that includes 13,790 bladder cancer cases and 343,502 controls of European ancestry were used for meta-analysis.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES

Log-additive associations of genetic variants were assessed using logistic regression models. A fixed-effects model was used for meta-analysis of the results. Stratified analyses were conducted to evaluate effect modification by sex and smoking status. A polygenic risk score (PRS) was generated on the basis of known and novel susceptibility variants and tested for interaction with smoking.

RESULTS AND LIMITATIONS

Multiple novel bladder cancer susceptibility loci (6p.22.3, 7q36.3, 8q21.13, 9p21.3, 10q22.1, 19q13.33) as well as improved signals in three known regions (4p16.3, 5p15.33, 11p15.5) were identified, bringing the number of independent markers at genome-wide significance (p < 5 × 10-8) to 24. The 4p16.3 (FGFR3/TACC3) locus was associated with a stronger risk for women than for men (p-interaction = 0.002). Bladder cancer risk was increased by interactions between smoking status and genetic variants at 8p22 (NAT2; multiplicative p value for interaction [pM-I] = 0.004), 8q21.13 (PAG1; pM-I = 0.01), and 9p21.3 (LOC107987026/MTAP/CDKN2A; pM-I = 0.02). The PRS based on the 24 independent GWAS markers (odds ratio per standard deviation increase 1.49, 95% confidence interval 1.44-1.53), which also showed comparable results in two prospective cohorts (UK Biobank, PLCO trial), revealed an approximately fourfold difference in the lifetime risk of bladder cancer according to the PRS (e.g., 1st vs 10th decile) for both smokers and nonsmokers.

CONCLUSIONS

We report novel loci associated with risk of bladder cancer that provide clues to its biological underpinnings. Using 24 independent markers, we constructed a PRS to stratify lifetime risk. The PRS combined with smoking history, and other established risk factors, has the potential to inform future screening efforts for bladder cancer.

PATIENT SUMMARY

We identified new genetic markers that provide biological insights into the genetic causes of bladder cancer. These genetic risk factors combined with lifestyle risk factors, such as smoking, may inform future preventive and screening strategies for bladder cancer.

A Nested Case-Control Study of Serum Per- and Polyfluoroalkyl Substances and Testicular Germ Cell Tumors among U.S. Air Force Servicemen

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) are a component of firefighting foams used at military installations. Although high PFAS exposures have been related to cancer risks among civilian populations, the effects for military personnel are unclear.

OBJECTIVES

We investigated associations between serum PFAS concentrations and testicular germ cell tumors (TGCT) among U.S. Air Force servicemen.

METHODS

This nested case-control study involved active-duty Air Force servicemen with sera from the Department of Defense Serum Repository. We selected 530 cases and 530 controls individually matched on birth date, race and ethnicity, year entered the service, and year of sample collection, with prediagnostic serum samples collected between 1988 and 2017. A second prediagnostic sample, collected a median of 4 y after the first, was selected for 187 case-control pairs. Seven PFAS were quantified using isotope-dilution tandem mass spectrometry. Odds ratios (ORs) and 95% confidence intervals (CIs) from conditional logistic regression adjusting for military grade, number of deployments, and, in some models, other PFAS, estimated associations between PFAS concentrations (categorized using quartiles among controls) and TGCT.

RESULTS

Elevated concentrations of some PFAS were observed for military employment in firefighting [perfluorooctanesulfonic acid (PFOS), perfluorohexanesulfonic acid (PFHxS), perfluorooctanoic acid] and service at a base with high PFAS concentrations in drinking water (PFHxS). Elevated PFOS concentrations in the second sample were positively associated with TGCT [OR for fourth vs. first quartile ( OR Q 4 ) = 2.6 , 95% CI: 1.1, 6.4; p trend = 0.02 ], including after adjustment for other PFAS (OR Q 4 = 4.6 , 95% CI: 1.4, 15.1; p trend = 0.009 ). Associations with PFOS in the first/only samples were weak and not statistically significant. Elevated concentrations of perfluorononanoic acid were inversely associated with TGCT, whereas results were null for other PFAS.

DISCUSSION

We identified service-related predictors of PFAS concentrations and increased TGCT relative risks with elevated PFOS concentrations among Air Force servicemen. These findings warrant further investigation in other populations and military service branches. https://doi.org/10.1289/EHP12603.

Biomarkers of gut barrier dysfunction and risk of hepatocellular carcinoma in the REVEAL-HBV and REVEAL-HCV cohort studies

Gut barrier dysfunction can result in the liver being exposed to an elevated level of gut-derived bacterial products via portal circulation. Growing evidence suggests that systemic exposure to these bacterial products promotes liver diseases including hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). However, prospective studies have not examined the association between biomarkers of gut barrier dysfunction and HCC risk in a population of hepatitis B or C viral (HBV/HCV) carriers. We investigated whether prediagnostic, circulating biomarkers of gut barrier dysfunction were associated with HCC risk, using the Risk Evaluation of Viral Load Elevation and Associated Liver Disease/Cancer (REVEAL)-HBV and REVEAL-HCV cohorts from Taiwan. REVEAL-HBV included 185 cases and 161 matched controls, and REVEAL-HCV 96 cases and 96 matched controls. The biomarkers quantitated were immunoglobulin A (IgA), IgG, and IgM against lipopolysaccharide (LPS) and flagellin, soluble CD14 (an LPS coreceptor), and LPS-binding protein (LBP). Odds ratios (ORs) and 95% confidence intervals (CIs) for associations between biomarker levels and HCC were calculated using multivariable-adjusted logistic regression. A doubling of the circulating levels of antiflagellin IgA or LBP was associated with a 76% to 93% increased risk of HBV-related HCC (OR per one unit change in log2 antiflagellin IgA = 1.76, 95% CI: 1.06-2.93; OR for LBP = 1.93, 95% CI: 1.10-3.38). None of the other markers were associated with an increased risk of HBV-related or HCV-related HCC. Results were similar when cases diagnosed in the first 5 years of follow-up were excluded. Our findings contribute to understanding the interplay of gut barrier dysfunction and primary liver cancer etiology.

Abstract 1944: Racial and ethnic disparities in U.S. clinical trials in liver cancer in the last nineteen years

Background: Accurate representation of ethnic/racial population subgroups in clinical trials is fundamental to ensure universal effectiveness of new therapies as well as to decrease disparities in oncology care. In 2020, Hispanic (Hisp) and Non-Hispanic Black (NHB) people constituted 19% and 14% of the U.S. population, respectively. As of 2019, Hisp and NHB proportionally made up 23.2% and 11.1% of hepatocellular carcinoma cases, respectively, and 22.6% and 8.3% of biliary tract cancer cases. We analyzed the enrollment of racial/ethnic groups of liver cancer trials in the U.S in the last twenty years.

Methods: A database search was performed in clinicaltrials.gov for interventional liver cancer studies based only in the U.S. with reported results from 09/2002-08/2022. A total of 3492 trials were identified; studies were excluded if non-interventional (N=168), recruited in a foreign site (N= 2422), results were missing (N=713), or were not liver specific (N=63), resulting in a total of 126 studies. We sought to quantify the enrollment of racial/ethnic subgroups.

Results: From a total of 126 studies, enrolling 5197 patients, 53.2% reported race/ethnicity; amongst these, 57.1% of patients were Non-Hispanic White, 14.5% were NHB, 9.9% were Hisp, 8.5% Asian, 0.4% American Indian and 0.2% Native Hawaiian/Pacific Islander. NIH-funded studies had higher rates of race/ethnicity reporting without reaching statistical significance (65.1% vs 47.0%, p= 0.053). The rate of race/ethnicity reporting between clinical trial phases (I- IV) was not statistically significant (p= 0.70).

Conclusions: 47% of U.S. liver cancer studies in the last twenty years in clinicaltrials.gov did not report race/ethnicity. The relative representation of NHB and Hispanics in these trials is lower than the incidence reported in the U.S. Race/ethnicity reporting in U.S.-based clinical trials may be beneficial.

Table 1: Demographics of U.S-only Clinical Trials of Liver Cancer By Funding By Trial Phase All NIH Non-NIH P- value Phase I or II P- value P- value Trials 126 43 83 - 105 - - Participants 5306 1557 3749 - 3325 - - Race and ethnicity reported 53.2% 65.1% 47.0% 0.053 57.1% 0.70 0.70 Race and Ethnicity NHW* 57.1% 57.7% 56.7% 0.86 60.2% NA NA NHB* 14.5% 11.2% 16.8% 0.07 15.1% NA NA Hisp* 9.9% 13.4% 7.4% 0.30 7.1% NA NA Asian 8.5% 9.9% 7.5% 0.57 7.9% NA NA AI* 0.4% 0.2% 0.5% 0.17 0.4% NA NA NH/PI* 0.2% 0.2% 0.2% 0.76 0.2% NA NA *NHW= Non-Hispanic White, NHB= Non-Hispanic Black, Hisp= Hispanic, AI= American Indian, NH/PI= Native Hawaiian/Pacific Islander

Citation Format: J. Alberto Maldonado, Barry I. Graubard, Katherine A. McGlynn, Tim F. Greten, Cecilia Monge. Racial and ethnic disparities in U.S. clinical trials in liver cancer in the last nineteen years [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1944.

Abstract 5228: Genome-wide association study and LD score regression analysis for cholangiocarcinoma

Cholangiocarcinoma (CCA) is a rare and aggressive cancer of the bile ducts, with a poor prognosis and limited treatment options. CCA are classified as intrahepatic and extrahepatic based on anatomical location. CCA are often diagnosed at an advanced stage because there are no effective tools for early detection. Although genome-wide association studies (GWASs) have discovered many genome-wide significant contributing risk loci, the genetic underpinning of cholangiocarcinoma remains poorly understood. To date, there is no cholangiocarcinoma-specific GWAS. We conducted GWAS of cholangiocarcinoma in 9,648 individuals of European ancestry using TOPMed reference panel. The putative associations in or near THSD7A on chromosome 7 (OR=2.61, P=7.13 × 10−8), ZBTB16 on 11 (OR=0.16, P=6.02 × 10−8) for non-PSC-related CCA, PUM3 on 9 (OR=10.74, P=6.12 × 10−8), AGBL1 on 15 (OR=2.08, P=5.67 × 10−8) for PSC-related CCA, and LINC02506 on 4 (OR=0.16, P=8.83 × 10−9) for extrahepatic CCA. We also implemented linkage disequilibrium score regression (LDSR) analysis to quantify the genetic correlation between phenotypes using publicly available GWAS summary statistics. Our study aimed to identify possible clinical and epidemiological traits associated with CCA. We identified numerous biomarkers, medical conditions, environmental and behavioral traits, and physical measurements showing high heritability, which is the proportion of phenotypic variance explained by all SNPs included in the analysis, and pairwise genetic correlation with CCA and other CCA subtypes. Elevations of selected biomarkers such as alkaline phosphatase, cystatin C, HbA1c, monocyte count, and white blood cell count show a positive genetic association with CCA in European-ancestry population. Also, autoimmune-mediated conditions show a strong positive genetic association with CCA, non-PSC related CCA, and intrahepatic CCA. The GWAS of CCA and CCA subtypes revealed potential genetic susceptibility associations and will allow us to compare the genetic architecture underlying CCA and other diseases of the bile ducts such as primary sclerosing cholangitis and liver cancer. LDSR provided an improved understanding of the genetic architecture between CCA and potential comorbid conditions and biomarkers. Mendelian randomization analysis will be needed to elucidate the causal relationship between CCA and traits of interest.

Citation Format: Younghun Han, Katherine A. McGlynn, Jinyoung Byun, Matthew A. Cooley, Manal M. Hassan, Christopher I. Amos, Lewis R. Roberts, The International Consortium for the Genetics of Biliary Tract Cancers. Genome-wide association study and LD score regression analysis for cholangiocarcinoma. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5228.

Dietary inflammatory and insulinemic potential, risk of hepatocellular carcinoma and chronic liver disease mortality

BACKGROUND

Diet modulates inflammation and insulin response and may be an important modifiable factor in the primary prevention of hepatocellular carcinoma (HCC) and chronic liver disease (CLD). We developed the empirical dietary inflammatory pattern (EDIP) and empirical dietary index for hyperinsulinemia (EDIH) scores to assess the inflammatory and insulinemic potentials of diet.

OBJECTIVE

We prospectively examined the associations of EDIP and EDIH at baseline with the following HCC risk and CLD mortality.

DESIGN

We followed 485,931 individuals in the NIH-AARP Diet and Health Study since 1995. Cox proportional hazards regression was used to calculate multivariable hazard ratios (HRs) and 95% confidence intervals (95%CIs).

RESULTS

We confirmed 635 incident HCC cases and 993 CLD deaths. Participants in the highest compared to those in the lowest EDIP quartile had 1.35 times higher risk of developing HCC (95% CI: 1.08-1.70, Ptrend =0.0005), and had 1.70 times higher CLD mortality (95% CI: 1.41-2.04, Ptrend <0.0001). For the same comparison, participants with highest EDIH were at increased risk of HCC (HR = 1.53, 95% CI: 1.20-1.95, Ptrend =0.0004), and CLD mortality (HR = 1.72, 95% CI: 1.42-2.01, Ptrend <0.0001). Similar positive associations of scores with HCC risk and CLD mortality were observed for both women and men. Moreover, individuals in both highest EDIP and EDIH tertiles had 92% increased HCC risk (95% CI: 1.43-2.58) and had 98% increased CLD mortality (95% CI: 1.27-3.08), compared with those in both lowest tertiles.

CONCLUSIONS

Our findings suggest that inflammation and hyperinsulinemia are potential mechanisms linking diet to HCC development and CLD mortality.

Multitrait genome-wide analyses identify new susceptibility loci and candidate drugs to primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a rare autoimmune bile duct disease that is strongly associated with immune-mediated disorders. In this study, we implemented multitrait joint analyses to genome-wide association summary statistics of PSC and numerous clinical and epidemiological traits to estimate the genetic contribution of each trait and genetic correlations between traits and to identify new lead PSC risk-associated loci. We identified seven new loci that have not been previously reported and one new independent lead variant in the previously reported locus. Functional annotation and fine-mapping nominated several potential susceptibility genes such as MANBA and IRF5. Network-based in silico drug efficacy screening provided candidate agents for further study of pharmacological effect in PSC.

Specific botanical groups of fruit and vegetable consumption and liver cancer and chronic liver disease mortality: a prospective cohort study

BACKGROUND

Beyond alcohol and coffee, the relationship between other dietary factors, including specific vegetables and fruits, and liver outcomes remains poorly understood.

OBJECTIVE

To evaluate the associations between fruit and vegetable intake with the risk of liver cancer and chronic liver disease (CLD) mortality.

METHODS

This study was based on the National Institutes of Health-American Association of Retired Persons Diet and Health Study, including 485,403 participants aged 50-71 y from 1995 to 1996. Fruit and vegetable intake was estimated using a validated food frequency questionnaire. Cox proportional hazards regression was used to estimate the multivariable hazard ratios (HR) and 95% confidence intervals (CI) for liver cancer incidence and CLD mortality.

RESULTS

During a median follow-up of 15.5 y, 947 incident liver cancers and 986 CLD deaths (other than liver cancer) were confirmed. A higher intake of total vegetables was associated with a lower risk of liver cancer (HRQuintile 5 vs. Quintile 1 = 0.72, 95% CI: 0.59, 0.89; Ptrend < 0.001). When further subclassified into botanical groups, the observed inverse association was mainly driven by lettuce and the cruciferous family (broccoli, cauliflower, cabbage, etc.) (Ptrend < 0.005). Additionally, higher total vegetable intake was associated with a lower risk of CLD mortality (HRQuintile5 vs. Quintile1 = 0.61, 95% CI: 0.50, 0.76; Ptrend < 0.001). Inverse associations were observed for lettuce, sweet potatoes, cruciferous vegetables, legumes, and carrots with CLD mortality (all Ptrend < 0.005). In contrast, total fruit intake was not associated with liver cancer or CLD mortality.

CONCLUSIONS

Higher intakes of total vegetables, especially lettuce and cruciferous vegetables, were associated with lower liver cancer risk. Higher intakes of lettuce, sweet potatoes, cruciferous vegetables, legumes, and carrots were associated with a lower risk of CLD mortality.

Age-incidence patterns of seminoma and nonseminoma among males and females in Germany and the United States, 2008-2016

BACKGROUND & OBJECTIVES

The comparison of the incidence of gonadal germ cell tumors among males and females can provide insights that cannot be gained by separately studying these tumors.

MATERIAL AND METHODS

Incidence data on male and female gonadal germ cell tumors were drawn from the cancer registries of North Rhine-Westphalia, Germany, and the United States Surveillance, Epidemiology and End Results program, for non-Hispanic White persons only, for the years 2008-2016. We estimated age-standardized and age-, and histology-specific incidence rates.

RESULTS

We included 21,840 male and 716 female gonadal germ cell tumors. Incidence rates among males were higher in Germany (95.8 per million, standard error [SE] 1.1) than in the United States (68.0, SE 0.6), while incidence rates among females were lower in Germany (1.9, SE 0.2) than in the United States (2.6, SE 0.1). The characteristic peak of infantile (age 0-4 years) germ cell tumors among males were missing among females. The age peak of ovarian germ cell tumors occurred 15-20 years earlier (Germany: 10-14 years, United States: 15-19 years) than the age peak of testicular germ cell tumors (30-34 years). The three most common testicular germ cell tumors histologies were seminoma, mixed germ cell tumors, and embryonal carcinoma Among females, the three most common ovarian germ cell tumors histologies were teratoma, yolk sac tumor, monodermal teratomas, and somatic-type tumors arising from dermoid cysts in both countries.

DISCUSSION

The characteristic peak of infantile (age 0-4 years) germ cell tumors among males was missing among females. The shapes of the age-specific incidence curves are similar for males and females in Germany and the United States, though with much lower incidence rates in females, suggesting a common pathogenesis.

CONCLUSION

The lower rates among females may be due to the lower number of initiated tumors in the absence of the Y-chromosome, and the earlier peak among females may be due to a younger age at puberty.

Enterohepatic Shunt-Driven Cholemia Predisposes to Liver Cancer

BACKGROUND & AIMS

Pathogenesis of hepatocellular carcinoma (HCC), which kills millions annually, is poorly understood. Identification of risk factors and modifiable determinants and mechanistic understanding of how they impact HCC are urgently needed.

METHODS

We sought early prognostic indicators of HCC in C57BL/6 mice, which we found were prone to developing this disease when fed a fermentable fiber-enriched diet. Such markers were used to phenotype and interrogate stages of HCC development. Their human relevance was tested using serum collected prospectively from an HCC/case-control cohort.

RESULTS

HCC proneness in mice was dictated by the presence of congenitally present portosystemic shunt (PSS), which resulted in markedly elevated serum bile acids (BAs). Approximately 10% of mice from various sources exhibited PSS/cholemia, but lacked an overt phenotype when fed standard chow. However, PSS/cholemic mice fed compositionally defined diets, developed BA- and cyclooxygenase-dependent liver injury, which was exacerbated and uniformly progressed to HCC when diets were enriched with the fermentable fiber inulin. Such progression to cholestatic HCC associated with exacerbated cholemia and an immunosuppressive milieu, both of which were required in that HCC was prevented by impeding BA biosynthesis or neutralizing interleukin-10 or programmed death protein 1. Analysis of human sera revealed that elevated BA was associated with future development of HCC.

CONCLUSIONS

PSS is relatively common in C57BL/6 mice and causes silent cholemia, which predisposes to liver injury and HCC, particularly when fed a fermentable fiber-enriched diet. Incidence of silent PSS/cholemia in humans awaits investigation. Regardless, measuring serum BA may aid HCC risk assessment, potentially alerting select individuals to consider dietary or BA interventions.

Association Study between Polymorphisms in DNA Methylation-Related Genes and Testicular Germ Cell Tumor Risk

BACKGROUND

Testicular germ cell tumors (TGCT), histologically classified as seminomas and nonseminomas, are believed to arise from primordial gonocytes, with the maturation process blocked when they are subjected to DNA methylation reprogramming. SNPs in DNA methylation machinery and folate-dependent one-carbon metabolism genes have been postulated to influence the proper establishment of DNA methylation.

METHODS

In this pathway-focused investigation, we evaluated the association between 273 selected tag SNPs from 28 DNA methylation-related genes and TGCT risk. We carried out association analysis at individual SNP and gene-based level using summary statistics from the Genome Wide Association Study meta-analysis recently conducted by the international Testicular Cancer Consortium on 10,156 TGCT cases and 179,683 controls.

RESULTS

In individual SNP analyses, seven SNPs, four mapping within MTHFR, were associated with TGCT risk after correction for multiple testing (q ≤ 0.05). Queries of public databases showed that three of these SNPs were associated with MTHFR changes in enzymatic activity (rs1801133) or expression level in testis tissue (rs12121543, rs1476413). Gene-based analyses revealed MTHFR (q = 8.4 × 10-4), methyl-CpG-binding protein 2 (MECP2; q = 2 × 10-3), and ZBTB4 (q = 0.03) as the top TGCT-associated genes. Stratifying by tumor histology, four MTHFR SNPs were associated with seminoma. In gene-based analysis MTHFR was associated with risk of seminoma (q = 2.8 × 10-4), but not with nonseminomatous tumors (q = 0.22).

CONCLUSIONS

Genetic variants within MTHFR, potentially having an impact on the DNA methylation pattern, are associated with TGCT risk.

IMPACT

This finding suggests that TGCT pathogenesis could be associated with the folate cycle status, and this relation could be partly due to hereditary factors.

Global patterns in testicular cancer incidence and mortality in 2020

With 74 500 new cases worldwide in 2020, testicular cancer ranks as the 20th leading cancer type, but is the most common cancer in young men of European ancestry. While testicular cancer incidence has been rising in many populations, mortality trends, at least those in high-income settings, have been in decline since the 1970s following the introduction of platinum-based chemotherapy. To examine current incidence and mortality patterns, we extracted the new cases of, and deaths from cancers of the testis from the GLOBOCAN 2020 database. In 2020, testicular cancer was the most common cancer in men aged 15 to 44 in 62 countries worldwide. Incidence rates were highest in West-, North- and South-Europe and Oceania (age-standardised rate, ASR ≥7/100 000), followed by North America (5.6/100 000 and lowest (<2/100 000) in Asia and Africa. The mortality rates were highest in Central and South America (0.84 and 0.54 per 100 000, respectively), followed by Eastern and Southern Europe, and Western and Southern Africa. The lowest mortality rates were in Northern Europe, Northern Africa and Eastern Asia (0.16, 0.14, 0.9 per 100 000, respectively). At the country level, incidence rates varied over 100-fold, from 10/100 000 in Norway, Slovenia, Denmark and Germany to ≤0.10/100 000 in Gambia, Guinea, Liberia, Lesotho. Mortality rates were highest in Fiji, Argentina and Mexico. Our results indicate a higher mortality burden in countries undergoing economic transitions and reinforce the need for more equitable access to testicular cancer diagnosis and treatment globally.

Prediction of nonalcoholic fatty liver disease using anthropometry and body fat measures by sex and race/ethnicity in the United States

OBJECTIVE

The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing in the United States and is strongly linked to obesity in many, but not all, racial/ethnic groups. It is conceivable that the lack of correspondence is related to differential fat distribution. The study objective was to examine which fat distribution measures best predicted NAFLD by sex within racial/ethnic groups.

METHODS

The analysis included 1,404 participants from the 2017-2018 National Health and Nutrition Examination Survey (NHANES). Area under the receiver operating characteristic curve (AUC) analyses compared the ability of dual-energy x-ray absorptiometry-measured percentage total fat and abdominal fat with measured BMI, waist circumference, and waist to height ratio to predict ultrasound transient-elastography-assessed NAFLD in each sex and racial/ethnic group.

RESULTS

AUC analysis found the best predictors of NAFLD among men were waist circumference and total abdominal fat area (AUC: 84.1%) and the best predictor among women was visceral fat (AUC: 85.2). NAFLD prediction by body fat measures, however, was similar between racial/ethnic groups.

CONCLUSIONS

The best predictors of NAFLD, using body fat distribution measures, vary by sex but not by racial/ethnic group.

Racial/ethnic disparities in hepatocellular carcinoma incidence and mortality rates in the United States, 1992-2018

BACKGROUND AND AIMS

HCC is characterized by racial/ethnic disparities in rates. Recent USA reports suggest that incidence has begun to decline, but it is not clear whether the declines have occurred among all groups, nor whether mortality has declined. Thus, the current study examined USA incidence and mortality between 1992 and 2018.

APPROACH & RESULTS

HCC incidence and incidence-based mortality data from the Surveillance, Epidemiology, and End Results program were used to calculate age-standardized rates by race/ethnicity, sex, and age. Trends were analyzed using joinpoint regression to estimate annual percent change (APC). Age-period-cohort models assessed the effects on trends of age, calendar period, and birth cohort. Overall, HCC incidence significantly declined between 2015 and 2018 (APC, -5.6%). Whereas most groups experienced incidence declines, the trends were most evident among Asians/Pacific Islanders, women, and persons <50 years old. Exceptions were the rates among non-Hispanic Black persons, which did not significantly decline (APC, -0.7), and among American Indians/Alaska Natives, which significantly increased (APC, +4.3%). Age-period-cohort modeling found that birth cohort had a greater effect on rates than calendar period. Among the baby boom cohorts, the 1950-1954 cohort had the highest rates. Similar to the overall incidence decline, HCC mortality rates declined between 2013 and 2018 (APC, -2.2%).

CONCLUSIONS

HCC incidence and mortality rates began to decline for most groups in 2015, but persistent differences in rates continued to exist. Rates among non-Hispanic Black persons did not decline significantly, and rates among American Indians/Alaska Natives significantly increased, suggesting that greater effort is needed to reduce the HCC burden among these vulnerable groups.

Body mass index trajectories, weight gain and risks of liver and biliary tract cancers

BACKGROUND

Little is known about the role of early obesity or weight change during adulthood in the development of liver cancer and biliary tract cancer (BTC).

METHODS

We investigated the associations of body mass index (BMI) and weight trajectories with the risk of liver cancer and BTC in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO). BMI was self-reported at ages 20, 50, and at enrollment. BMI trajectories were determined using latent class growth models. Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

During a median follow-up of 15.9 years among 138,922 participants, 170 liver cancer and 143 BTC cases were identified. Compared with those whose BMI does not exceed 25 kg/m2, participants with BMI exceeding 25 kg/m2 at age 20 had increased risks of liver cancer (HR = 2.03, 95% CI: 1.26-3.28) and BTC (HR = 1.99, 95% CI: 1.16-3.39). Compared to participants maintaining normal BMI until enrollment, trajectory of normal weight at age 20 to obesity at enrollment was associated with increased risk for liver cancer (HR = 2.50, 95% CI: 1.55-4.04) and BTC (HR = 1.83, 95% CI: 1.03-3.22). Compared to adults with stable weight (+/-5kg) between age 20 to 50 years, weight gain ≥20 kg between ages 20 to 50 years had higher HRs of 2.24 (95%CI: 1.40-3.58) for liver cancer and 1.86 (95% CI: 1.12-3.09) for BTC.

CONCLUSIONS

Being overweight/obese at age 20, and BMI trajectories that result in being overweight and/or obese, may increase risk for both liver cancer and BTC.

Outdoor light at night and risk of liver cancer in the NIH-AARP diet and health study

PURPOSE

Accumulating evidence suggests that light at night (LAN) disrupts circadian rhythms and may increase risk of liver cancer. However, there is no population-based study that examined LAN and liver cancer risk. Therefore, we aimed to investigate the association between outdoor LAN and liver cancer risk in a prospective cohort.

METHODS

Residential outdoor LAN level was measured from satellite imagery in the NIH-AARP Diet and Health Study, a prospective cohort of 451,945 men and women, 50-71 years old. Relative risks (RR) and 95% confidence intervals (CIs) were estimated using Cox proportional hazard models that adjusted for known risk factors for liver cancer and neighborhood characteristics.

RESULTS

During an average 12.2 years of follow-up, 897 liver cancers, 603 of which were hepatocellular carcinomas (HCC), were diagnosed. Residential outdoor LAN was not associated with risk of liver cancer (RR_{Q5 vs Q1} = 0.96, 95% CI: 0.77-1.20, p trend = 0.771) or HCC (RR_{Q5 vs Q1} = 0.82, 95% CI: 0.62-1.07, p trend = 0.425).

CONCLUSION

No association between outdoor LAN and risk of liver cancer or HCC may in part be due to limitations in LAN assessment. More studies on the relationship between light intensity, duration, timing, and wavelength and liver cancer are warranted.

New-onset cancer cases in FDA's Sentinel System: a large distributed system of US electronic healthcare data

BACKGROUND

Evaluations of cancer etiology and safety and effectiveness of cancer treatments are predicated on large numbers of patients with sufficient baseline and follow-up data. To assess feasibility of FDA's Sentinel System's electronic healthcare data for surveillance of malignancy onset and examination of product safety, this study examined patterns of enrollment surrounding new-onset cancers.

METHODS

Using a retrospective cohort of patients based on administrative claims, we identified incident events of 19 cancers among 292.5 million health plan members from January 2000 through February 2020 using International Classification of Diseases (ICD) diagnosis codes. Annual incident cases were stratified by sex, age, medical and drug coverage, and insurer type. Descriptive statistics were calculated for observable time prior to and following diagnosis.

RESULTS

We identified 10,697,573 incident cancer events among members with medical coverage. When drug coverage was additionally required, number of incident cancers was reduced by 41%. Medicare data contributed 61% of cases, with similar duration trends as other insurers. Mean duration of follow-up prior to diagnosis ranged from 4.0-4.6 years, while follow-up post diagnosis ranged from 1.1-3.3 years. Approximately a third (36.1%) had at least 2 years both prior to and following diagnosis.

CONCLUSIONS

The FDA Sentinel System's electronic healthcare data may be useful for characterizing relatively short latency cancer risk, examining cancer drug utilization and safety post diagnosis, and conducting surveillance for acute adverse events among patients with cancers.

IMPACT

A national distributed system with electronic health data, the Sentinel system provides opportunity for rapid pharmacoepidemiologic assessments relevant in oncology.

Circulating bile acid concentrations and non-alcoholic fatty liver disease in Guatemala

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a major liver disease worldwide. Bile acid dysregulation may be a key feature in its pathogenesis and progression.

AIMS

To characterise the relationship between bile acid levels and NAFLD at the population level METHODS: We conducted a cross-sectional study in Guatemala in 2016 to examine the prevalence of NAFLD. Participants (n = 415) completed questionnaires, donated blood samples and had a brief medical exam. NAFLD was determined by calculation of the fatty liver index. The levels of 15 circulating bile acids were determined by LC-MS/MS. Adjusted prevalence odds ratios (POR_adj ) and 95% CI were calculated to examine the relationships between bile acid levels (in tertiles) and NAFLD.

RESULTS

Persons with NAFLD had significantly higher levels of the conjugated primary bile acids glycocholic acid (GCA) (POR_{adj T3 vs T1}  = 1.85), taurocholic acid (TCA) (POR_{adj T3 vs T1}  = 2.45) and taurochenodeoxycholic acid (TCDCA) (POR_{adj T3 vs T1}  = 2.10), as well as significantly higher levels the unconjugated secondary bile acid, deoxycholic acid (DCA) (POR_{adj T3 vs T1}  = 1.78) and its conjugated form, taurodeoxycholic acid (TDCA) (POR_{adj T3 vs T1}  = 1.81).

CONCLUSIONS

The bile acid levels of persons with and without NAFLD differed significantly. Among persons with NAFLD, higher levels of the conjugated forms of CA (i.e. GCA, TCA) and the secondary bile acids that derive from CA (i.e. DCA, TDCA) may indicate there is hepatic overproduction of CA, which may affect the liver via aberrant signalling mediated by the bile acids.

Prospective associations of hemoglobin A1c and c-peptide with risk of diabetes-related cancers in the Cancer Prevention Study-II Nutrition Cohort

Self-reported type 2 diabetes mellitus (T2DM) is a risk factor for many cancers, suggesting its pathology relates to carcinogenesis. We conducted a case-cohort study to examine associations of hemoglobin A1c (HbA1c) and c-peptide with cancers associated with self-reported T2DM. This study was drawn from a prospective cohort of 32,383 women and men who provided blood specimens at baseline: c-peptide and HbA1c were assessed in 3,000 randomly selected participants who were cancer-free-at-baseline and an additional 2,281 participants who were cancer-free-at-baseline and subsequently diagnosed with incident colorectal, liver, pancreatic, female breast, endometrial, ovarian, bladder, or kidney cancers. Weighted-Cox regression models estimated hazards ratios (HRs) and 95% confidence intervals (CI), adjusted for covariates. C-peptide was associated with higher risk of liver cancer (per standard deviation (SD) HR: 1.80; 95%CI: 1.32-2.46). HbA1c was associated with higher risk of pancreatic cancer (per SD HR: 1.21 95%CI 1.05-1.40) and with some suggestion of higher risks for all-cancers-of-interest (per SD HR: 1.05; 95%CI: 0.99-1.11) and colorectal (per SD HR: 1.09; 95%CI: 0.98-1.20), ovarian (per SD HR: 1.18; 95%CI 0.96-1.45) and bladder (per SD HR: 1.08; 95%CI 0.96-1.21) cancers. Compared to no self-reported T2DM and HbA1c <6.5% (reference group), self-reported T2DM and HbA1c <6.5% (i.e., T2DM in good glycemic control) was not associated with risk of colorectal cancer, whereas it was associated with higher risks of all-cancers-of-interest combined (HR: 1.28; 95%CI: 1.01-1.62), especially for breast and endometrial cancers. Additional large, prospective studies are needed to further explore the roles of hyperglycemia, hyperinsulinemia, and related metabolic traits with T2DM-associated cancers to better understand the mechanisms underlying the self-reported T2DM-cancer association and to identify persons at higher cancer risk.

Sweetened beverage consumption and risk of liver cancer by diabetes status: A pooled analysis

BACKGROUND

Consumption of sweetened beverages has been linked to several risk factors for liver cancer including diabetes. Studies investigating the role of sweetened beverage consumption and liver cancer, however, are limited. As persons with diabetes are advised against consumption of sugar, the objective of this study was to examine the role of sweetened beverage consumption and liver cancer risk by diabetes status.

METHODS

Data from two U.S. cohorts: the NIH-AARP Diet and Health Study, and the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial were harmonized and pooled. Hazard ratios and 95%CI were estimated using Cox proportional hazard models stratified by median follow-up time.

RESULTS

Among persons without diabetes, there were no statistical evidence of associations between liver cancer and consumption of sweetened beverages overall, sugar sweetened beverages (SSB), or artificially sweetened beverages (ASB). Sugar sweetened (SS) soda consumption, however, was associated with liver cancer in the first follow-up interval (HR:1.18. 95%CI: 1.03, 1.35). In contrast, among persons with diabetes, there were significant associations between liver cancer and consumption of sweetened beverages overall (HR: 1.12, 95%CI 1.01, 1.24), ASBs (HR: 1.13, 95% CI: 1.02, 1.25), soda overall (HR: 1.13, 95% CI: 1.00, 1.26) and artificially sweetened (AS) soda (HR: 1.13, 95% CI: 1.01, 1.27) in the first follow-up interval.

CONCLUSIONS

Increased soda consumption may be associated with risk of liver cancer. The results suggest that decreasing consumption of SS soda by persons without diabetes, and AS soda by persons with diabetes, could be associated with reduced liver cancer risk.

Abstract 730: Fruit and vegetable consumption and risk of liver cancer and liver disease mortality: A prospective cohort study

Background: In the US, liver cancer incidence has been tripled since the 1980s. Beyond alcohol and coffee, the relationship between other dietary factors and liver cancer remains poorly understood. One objective of this study is to comprehensively evaluate the relationship between overall and specific botanical groups of fruit and vegetable intake with liver cancer risk. Although liver disease mortality is the 11th leading cause of death in the US, its relationship with diet remains unclear. We also aimed to evaluate the association between fruit and vegetable intake and liver disease mortality.

Methods: The study was conducted in the US NIH-AARP Diet and Health Study with 470,653 participants aged 50-71 years in 1995-1996. Fruits (14 items plus fruit juice) and vegetables (23 items without white potatoes included) were estimated using a validated Food Frequency Questionnaire. Cox proportional hazards regression modeling was used to estimate the multivariable hazard ratios (HR) and 95% confidence intervals (95% CI) for liver cancer incidence and liver disease mortality. We adjusted a priori for potential confounders including age, sex, education, race, alcohol intake, body mass index, smoking, total energy intake, physical activity, diabetes, and aspirin use.

Results: During a median follow-up of 15.5 years, 899 incident liver cancers and 934 chronic liver disease deaths occurred. Higher intake of total vegetables was associated with a lower risk of liver cancer (HRQuintile 5 vs Quintile 1=0.66, 95%CI=0.53-0.82, Ptrend&lt;0.01). When further subclassified into botanical groups, the observed inverse association was mainly driven by Cruciferae (broccoli, cauliflower, cabbage, et. al., HRQ5 vs Q1=0.64, 95%CI=0.52-0.79, Ptrend&lt;0.01), Compositae (lettuce, HRQ5 vs Q1=0.67, 95%CI=0.54-0.83, Ptrend&lt;0.01), Leguminosae (dried beans, string beans and peas, HRQ5 vs Q1=0.77, 95%CI=0.62-0.94, Ptrend=0.01), and Umbelliferae (carrots, HRQ5 vs Q1=0.77, 95%CI=0.62-0.95, Ptrend=0.01). Additionally, higher total vegetable intake was associated with a lower risk of liver disease mortality (HRQ5 vs Q1=0.60, 95%CI=0.49-0.74, Ptrend&lt;0.01). Inverse associations were observed for lettuce, cruciferous vegetables, legumes, and carrots and liver disease mortality (all Ptrend&lt;0.01). In contrast, total fruit intake was not associated with liver cancer (HRQ5 vs Q1=0.96, 95%CI=0.77-1.19, Ptrend=0.29) or liver disease mortality (HRQ5 vs Q1=1.07, 95%CI=0.87-1.32, Ptrend=0.71).

Conclusions: Based on a large prospective US cohort study, higher intakes of total vegetables, and especially lettuce, cruciferous vegetables, legumes, and carrots, were associated with lower liver cancer incidence and liver disease mortality.

Citation Format: Longgang Zhao, Lina Jin, Jessica L. Petrick, Fenglei Wang, Tang Li, Hongmei Zeng, Stephanie A. Smith-Warner, A. Heather Eliassen, Fang Fang Zhang, Peter T. Campbell, Edward Giovannucci, Linda M. Liao, Susan E. Steck, Katherine A. McGlynn, Xuehong Zhang. Fruit and vegetable consumption and risk of liver cancer and liver disease mortality: A prospective cohort study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 730.

Abstract 20: Cancer incidence in the U.S. military: An updated analysis

Background: Active duty military service members and the general US population differ in several ways related to cancer occurrence. This study aimed to update and expand our previous study which compared incidence of six cancers between the U.S. military and general populations.

Methods: Cancers included in this study were pathologically confirmed malignant lung, colorectal, testicular, prostate, cervical and breast tumors diagnosed 1990-2013. The study populations were men and women aged 20-59 in the US active duty military and the population in nine areas covered by the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) cancer registry program. Military data were from the Department of Defense’s Automated Central Tumor Registry (ACTUR) and Defense Manpower Data Center. Age adjusted rates in ACTUR and SEER and incidence rate ratios (IRR) and 95% confidence intervals (95% CI) comparing ACTUR to SEER were calculated. Comparisons were made by sex, race, and cancer stage.

Results: Age adjusted incidence rates of colorectal cancer were significantly lower in ACTUR than SEER among White (IRR 0.78; 95% CI 0.72-0.84) and Black men (IRR 0.86; 95% CI 0.74-1.00), respectively. Lung cancer incidence was lower in ACTUR than SEER among White (IRR 0.55; 95% CI 0.49-0.62) and Black men (IRR 0.34; 95% CI 0.26-0.42) and White women (IRR 0.74; 95% CI 0.53-0.98). Whites in ACTUR had significantly lower incidence of testicular cancer (IRR 0.92; 95% CI 0.88-0.96). Lower incidence of cervical cancer in ACTUR was observed among both Whites (IRR 0.82; 95% CI 0.69-0.97) and Blacks (IRR 0.39; 95% CI 0.27-0.54). Incidence of prostate cancer was higher in ACTUR than SEER among both Whites (IRR 2.31; 95% CI 2.18-2.45) and Blacks (IRR 2.35; 95% CI 2.13-2.58). Results by tumor stage showed similar results between the ACTUR and SEER populations for regional and distant tumors, while no differences between the two were observed for localized tumors, except in the case of prostate cancer. Incidence of localized and regional prostate tumors was higher in ACTUR than SEER, while there was no significant difference in distant tumors.

Conclusion: Active duty service members had lower age adjusted incidence rates of colorectal, lung, testicular, and cervical cancers, but higher rates of prostate cancer than the general US population. While these findings may result from the combined effects of many factors, the lower incidence in the military may be associated with healthier status of service members. In addition, universal health care for active duty military may lead to earlier diagnosis of some tumors, such as prostate cancer, in the military.

Disclaimer: The contents of this publication are the sole responsibility of the authors and do not necessarily reflect the views, opinions or policies of USUHS, HJF, the DoD or the Departments of the Army, Navy or Air Force. Mention of trade names, commercial products or organizations does not imply endorsement by the US Government.

Citation Format: Julie A. Bytnar, Katherine A. McGlynn, Craig D. Shriver, Kangmin Zhu. Cancer incidence in the U.S. military: An updated analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 20.

Liver cancer mortality in Mexico: trend analysis from 1998 to 2018

Objective. To examine overall, sex, and state-specific liver cancer mortality trends in Mexico. Materials and meth­ods. Joinpoint regression was used to examine the trends in age-standardized mortality rates of liver cancer between 1998-2018. Estimated annual percent change with 95% confi­dence intervals (95%CI) were computed. Age-period-cohort models were used to assess the effects of age, calendar year, and birth cohort. Results. The state-specific mortality rates ranged from 3.34 (Aguascalientes) to 7.96 (Chiapas) per 100 000 person-years. Sex-specific rates were roughly equal, nationwide. Overall, we observed a statistically significant decrease in liver cancer mortality rates between 1998-2018 (annual percent change, -0.8%; 95%CI -1.0, -0.6). The overall age-period-cohort models suggest that birth cohort may be the most important factor driving the trends. Conclusions. While there was overall decline in liver cancer mortality, differences in rates by region were observed. The regional differences may inform future studies of liver cancer etiology across the country.  

Aflatoxin levels and prevalence of TP53 aflatoxin-mutations in hepatocellular carcinomas in Mexico

Objective. To determine the exposure to aflatoxin B1 (AFB1) in southern Mexico and the presence of the aflatoxin signature mutation in hepatocellular carcinoma (HCC) tissue from patients from a cancer referral center. Materials and methods. We estimated the prevalence and distribution of AFB1 in a representative sample of 100 women and men from Chiapas using the National Health and Nutrition Survey 2018-19. We also examined the presence of the aflatoxin signature mutation in codon 249 (R249S), and other relevant mutations of the TP53 gene in HCC tissue blocks from 24 women and 26 men treated in a national cancer referral center. Results. The prevalence of AFB1 in serum samples was 85.5% (95%CI 72.1-93.1) and the median AFB1 was 0.117 pg/μL (IQR, 0.050–0.350). We detected TP53 R249S in three of the 50 HCCs (6.0%) and observed four other G>T transversions potentially induced by AFB1. Conclusion. Our analysis provides evidence that AFB1 may have a relevant role on HCC etiology in Mexico.

Assessing the Validity of Normalizing Aflatoxin B1-Lysine Albumin Adduct Biomarker Measurements to Total Serum Albumin Concentration across Multiple Human Population Studies

The assessment of aflatoxin B₁ (AFB₁) exposure using isotope-dilution liquid chromatography-mass spectrometry (LCMS) of AFB₁-lysine adducts in human serum albumin (HSA) has proven to be a highly productive strategy for the biomonitoring of AFB₁ exposure. To compare samples across different individuals and settings, the conventional practice has involved the normalization of raw AFB₁-lysine adduct concentrations (e.g., pg/mL serum or plasma) to the total circulating HSA concentration (e.g., pg/mg HSA). It is hypothesized that this practice corrects for technical error, between-person variance in HSA synthesis or AFB₁ metabolism, and other factors. However, the validity of this hypothesis has been largely unexamined by empirical analysis. The objective of this work was to test the concept that HSA normalization of AFB₁-lysine adduct concentrations effectively adjusts for biological and technical variance and improves AFB₁ internal dose estimates. Using data from AFB₁-lysine and HSA measurements in 763 subjects, in combination with regression and Monte Carlo simulation techniques, we found that HSA accounts for essentially none of the between-person variance in HSA-normalized (R² = 0.04) or raw AFB₁-lysine measurements (R² = 0.0001), and that HSA normalization of AFB₁-lysine levels with empirical HSA values does not reduce measurement error any better than does the use of simulated data (n = 20,000). These findings were robust across diverse populations (Guatemala, China, Chile), AFB₁ exposures (10⁵ range), HSA assays (dye-binding and immunoassay), and disease states (healthy, gallstones, and gallbladder cancer). HSA normalization results in arithmetic transformation with the addition of technical error from the measurement of HSA. Combined with the added analysis time, cost, and sample consumption, these results suggest that it may be prudent to abandon the practice of normalizing adducts to HSA concentration when measuring any HSA adducts—not only AFB₁-lys adducts—when using LCMS in serum/plasma.

Associations between aflatoxin B 1 ‐albumin adduct levels with metabolic conditions in Guatemala: A cross‐sectional study

Background and Aims

Metabolic conditions such as obesity, type 2 diabetes, metabolic syndrome, and nonalcoholic fatty liver disease (NAFLD) are highly prevalent in Guatemala and increase the risk for a number of disorders, including hepatocellular carcinoma (HCC). Aflatoxin B₁ (AFB₁) levels are also notably elevated in the population and are known to be associated with HCC risk. Whether AFB₁ also contributes to the high prevalence of the metabolic disorders has not been previously examined. Therefore, the purpose of this study was to assess the association between AFB₁ and the metabolic conditions.

Methods

Four‐hundred twenty‐three individuals were included in the study, in which AFB₁‐albumin adduct levels were measured in sera. Metabolic conditions included diabetes, obesity, central obesity, metabolic syndrome, and NAFLD. Crude and adjusted prevalence odds ratios (PORs) and 95% confidence intervals (95% CI) were estimated for the associations between the metabolic conditions and AFB₁‐albumin adduct levels categorized into quartiles.

Results

The study found a significant association between AFB₁‐albumin adduct levels and diabetes (Q4 vs Q1 POR = 3.74, 95%CI: 1.71‐8.19; P‐trend .003). No associations were observed between AFB₁‐albumin adduct levels and the other conditions.

Conclusions

As diabetes is the metabolic condition most consistently linked to HCC, the possible association between AFB₁ exposure and diabetes may be of public health importance. Further studies are warranted to replicate the findings and examine potential mechanisms.

Agreement Between the Prevalence of Nonalcoholic Fatty Liver Disease Determined by Transient Elastography and Fatty Liver Indices

Nonalcoholic fatty liver disease (NAFLD) is a global public health problem linked to the rising prevalence of obesity and metabolic disorders.1 Accurate estimates of NAFLD in populations are challenging because the gold standard for detection is liver biopsy, an invasive procedure that precludes its use in research settings.2 NAFLD can also be detected via noninvasive imaging, such as ultrasound, magnetic resonance imaging-determined proton density fat fraction, magnetic resonance spectroscopy, and the controlled attenuation parameter derived via transient elastography (CAP-TE).2 Given the complexities of imaging in population studies, however, many estimates have been based on calculated indices, such as the Fatty Liver Index (FLI)3 and the Hepatic Steatosis Index (HSI).4 Concern has been raised that the indices underestimate the prevalence of NAFLD,5 thus downplaying the scope of the public health challenge. Ability to examine whether these concerns are substantive has been provided by a recent study of the US population. Using data from the study, it was reported that the US prevalence of CAP-TE-determined NAFLD was 47.8%.6 The current analysis used data from the same national study to examine how well the fatty liver indices corresponded to CAP-TE-determined NAFLD. Because most persons with NAFLD reportedly have elevated alanine aminotransferase (ALT) levels,7 the correspondence between elevated ALT and CAP-TE was also examined.

Proximity to endocrine-disrupting pesticides and risk of testicular germ cell tumors (TGCT) among adolescents: A population-based case-control study in California

BACKGROUND

The incidence of testicular germ cell tumors (TGCT) is increasing steadily in the United States, particularly among Latinos. TGCT is thought to be initiated in utero and exposure to endocrine-disrupting chemicals, suspected contributors to TGCT pathogenesis, during this critical developmental period may contribute to the rise.

OBJECTIVES

To assess the relationship between fetal exposure to agricultural endocrine-disrupting pesticides (EDPs) and TGCT risk among adolescents in a diverse population in California.

METHODS

We conducted a registry-based case-control study of TGCT. Cases, diagnosed between 1997 and 2011, were 15-19 years of age (n = 381). Controls were matched on birth year and race/ethnicity (n = 762). Quantities (kilograms) of 33 pesticides applied within 3 km and 1 km radii of each individual's address before birth were estimated using the Pesticide Use Reporting database. Odds ratios (OR), 95% confidence intervals (CI), and population attributable risk (PAR) were calculated for each EDP (using log-2 transformed values). Risk models considered race/ethnicity, birth year, and neighborhood socioeconomic status.

RESULTS

A doubling of nearby acephate applications (3 km and 1 km radii) and malathion applications (1 km radius) was associated with increased risks of TGCT among Latinos only (OR = 1.09; 95% CI:1.01-1.17; 1.30; 95% CI:1.08-1.57, and 1.19; 95% CI:1.01-1.39, respectively), whereas application of carbaryl within a 3 km radius increased TGCT risk in non-Latinos only (OR = 1.14, 95% CI:1.01-1.28). We estimate that acephate was associated with approximately 10% of the TGCT PAR, malathion with 3% and carbaryl with 1%.

CONCLUSIONS

TGCT among adolescents in California was associated with prenatal residential proximity to acephate and malathion among Latinos, and with carbaryl among non-Latinos. These results suggest that the rise in TGCT risk among Latinos may be associated with exposure to these pesticides.

Higher intake of whole grains and dietary fiber are associated with lower risk of liver cancer and chronic liver disease mortality

The relationship between dietary factors and liver disease remains poorly understood. This study evaluated the associations of whole grain and dietary fiber intake with liver cancer risk and chronic liver disease mortality. The National Institutes of Health–American Association of Retired Persons Diet and Health Study cohort recruited 485, 717 retired U.S. participants in 1995–1996. Follow-up through 2011 identified 940 incident liver cancer cases and 993 deaths from chronic liver disease. Compared with the lowest, the highest quintile of whole grain intake was associated with lower liver cancer risk (Hazard ratio [HR]_{Q5 vs. Q1} = 0.78, 95% confidence interval [CI]: 0.63–0.96) and chronic liver disease mortality (HR_{Q5 vs. Q1} = 0.44, 95% CI: 0.35–0.55) in multivariable Cox models. Dietary fiber was also associated with lower liver cancer risk (HR_{Q5 vs. Q1} = 0.69, 95% CI: 0.53–0.90) and chronic liver disease mortality (HR_{Q5 vs. Q1} = 0.37, 95% CI: 0.29–0.48). Fiber from vegetables, beans and grains showed potential protective effect. Here, we show that higher intake of whole grain and dietary fiber are associated with lower risk of liver cancer and liver disease mortality.

Higher intake of dietary fiber and whole grains are associated with reduced risk of various diseases including some cancers. Here, the authors estimate reductions in liver cancer of 22% and 31% and chronic liver disease mortality of 56% and 63% associated with increased whole grain and dietary fiber intake, respectively.

Comparative study of survival among small cell lung cancer patients in the U.S. military health system and those in the surveillance, epidemiology, and end results (SEER) program

PURPOSE

The U.S. military health system provides universal health care access to beneficiaries. However, whether the universal access has translated into improved patient outcome is unknown. We compared survival of small-cell lung cancer patients in the military health system with that in the U.S. general population. Stage and receipt of cancer treatment were also compared to see if they could contribute to survival difference.

METHODS

The data were obtained from The Department of Defense's Automated Central Tumor Registry (ACTUR) and the national Surveillance, Epidemiology, and End Results (SEER) program, respectively. ACTUR (N = 3040) and SEER patients (N = 12,160) were matched on age, sex, race and diagnosis year. Multivariable Cox regression model was used to compare all-cause mortality between ACTUR and SEER. Multivariable logistic regression was performed to compare cancer stage and treatment.

RESULTS

ACTUR patients exhibited significantly better survival than SEER counterparts (HR = 0.77, 95% CI= 0.71-0.83). ACTUR and SEER patients had similar stage, but ACTUR patients were more likely to receive radiation treatment (OR = 1.26, 95% CI = 1.12-1.42). The survival advantage of ACTUR patients remained across all tumor stages and radiation groups.

CONCLUSIONS

Survival of small-cell lung cancer patients with universal health care access had better survival than similar patients in the U.S. general population. Future studies are warranted to identify factors that may contribute to the improved survival.