Publications by authors named "Iona Cheng"
Living in racially and ethnically segregated neighborhoods may increase the risk of breast cancer. We examined associations between neighborhood racial and ethnic composition typology and incident primary invasive breast cancer risk in a population-based sample of 102,615 African American/Black, Japanese American, Native Hawaiian, Latino, and White females residing in California and Hawaii from the Multiethnic Cohort (MEC) study between 1993-2019. Hazard ratios (HRs) and 95% confidence intervals (CI) were estimated using multivariable Cox proportional hazards regression.
View Article and Find Full Text PDFBackground: Varying obesogenic inherited predisposition in early to later life may differentially impact colorectal cancer (CRC) development. Previous Mendelian randomization (MR) studies, conducted in populations of European genetic similarity, have not observed any significant associations between early life body weight with CRC risk. However, it remains unclear whether body mass index (BMI) at different early lifetime points is causally related with CRC risk in both Europeans and East Asian populations.
View Article and Find Full Text PDFBackground: Cigarette smoking is the leading cause of preventable mortality. Both neighborhood- and individual-level socioeconomic status (SES) are inversely associated with smoking. However, their joint effect on smoking behavior has not been evaluated.
View Article and Find Full Text PDFArticle Synopsis
- Lung cancer is a major cause of death among Asian American females, including those from Chinese, Korean, Japanese, and Vietnamese backgrounds, even though smoking rates in this group are low.
- Over 80% of Asian American females diagnosed with lung cancer have never smoked, contradicting general smoking-related lung cancer trends, and rates in non-smokers seem to be on the rise.
- Key risk factors for lung cancer in this demographic include family history, pre-existing lung conditions, exposure to cooking fumes and second-hand smoke, and unique genetic mutations, indicating a need for further research tailored to this population.
Disparities in cancer stage shifts associated with the COVID-19 pandemic in California, 2020-2021.
Cancer Epidemiol Biomarkers Prev
October 2024
Background: The COVID-19 pandemic and associated shutdowns disrupted healthcare access and resulted in decreased cancer screenings. Cancer diagnosis delays have concerning downstream effects on late-stage cancer, especially for marginalized populations.
Methods: The study population included 349,458 adults in the California Cancer Registry diagnosed with cancer between January 2019-December 2021, during which California experienced two stay-at-home orders.
Purpose: Few studies have examined whether the incidence rates of invasive breast cancer among Asian American, Native Hawaiian, and Pacific Islander (AANHPI) populations differ by the neighborhood social environment. Thus, we examined associations of ethnic enclave and neighborhood socioeconomic status (nSES) with breast cancer incidence rates among AANHPI females in California.
Methods: A total of 14,738 AANHPI females diagnosed with invasive breast cancer in 2008-2012 were identified from the California Cancer Registry.
Article Synopsis
- - The study analyzed a diverse group of 9,639 women with first primary invasive breast cancer to identify risk factors for second primary breast cancer (SBC), focusing on both contralateral and ipsilateral cases.
- - Results showed that younger women with ER/PR-negative cancer and family history had increased risk of contralateral SBC, while older women showed higher risk linked to family history and lifestyle factors like being overweight and alcohol consumption.
- - The research highlighted persistent elevated risks for SBC among African American, Asian American, and Hispanic women compared to non-Hispanic White women, suggesting the need for better screening and tailored risk assessments for different racial and ethnic groups.
Article Synopsis
- Recent studies indicate that exposure to fine particulate matter (PM) is linked to an increased risk of breast cancer, particularly among diverse populations, but data is limited.
- In a large study of 58,358 women from the Multiethnic Cohort in California, researchers found a significant association between PM and breast cancer incidence, noting variations based on family history but not on race or hormone receptor status.
- The study emphasizes the need for both personal and population-level strategies to reduce PM exposure in order to help prevent breast cancer, especially in areas where incidence rates are rising.
Racial and ethnic differences in second primary lung cancer risk among lung cancer survivors.
JNCI Cancer Spectr
September 2024
Article Synopsis
- Recent advancements in lung cancer treatments have led to increased survival rates for patients, but a higher risk of second primary lung cancer (SPLC) is now a concern, particularly in Hispanic populations whose SPLC risk remains unclear.
- Using a dataset from the Multiethnic Cohort followed over several years, the study discovered that although Hispanics had a lower initial lung cancer incidence compared to Whites and Blacks, they exhibited a higher SPLC incidence following initial lung cancer diagnosis.
- The findings indicate that Hispanics have a significantly higher SPLC incidence rate, likely due to better survival after initial lung cancer, prompting the need for ongoing monitoring to address racial disparities in lung cancer outcomes.
Background: The Oncotype DX Genomic Prostate Score (ODX-GPS) is a gene expression assay that predicts disease aggressiveness. The objective of this study was to identify sociodemographic and regional factors associated with ODX-GPS uptake.
Methods: Data from Surveillance Epidemiology and End Results registries on men with localized prostate cancer with a Gleason score of 3 + 3 or 3 + 4, PSA ≤20 ng/mL, and stage T1c to T2c disease from 2013 through 2017 were linked with ODX-GPS data.
Context: The distribution of body fat has been linked to circulating levels of lipids and sex-steroid hormones. The cholesterol metabolite and endogenous selective estrogen receptor modulator, 27-hydroxychlolesterol (27HC), may be influenced by adiposity phenotypes, particularly among females. No study has examined the relationships of 27HC and steroid hormones with adiposity phenotypes.
View Article and Find Full Text PDFReporting tumor genomic test results to SEER registries via linkages.
J Natl Cancer Inst Monogr
August 2024
Article Synopsis
- Precision medicine is increasingly important in cancer care, but tumor genomic data has been lacking in the National Cancer Institute's SEER Program, limiting research on molecular subtypes.
- To improve this, the SEER Program has implemented a centralized process to link cancer cases in their registries with genomic test results from molecular labs, using specialized software and a trusted third party for data handling.
- Recent linkages have included various OncotypeDX tests and results from other genomic classifiers, which facilitate the research community's access to valuable, de-identified data for cancer studies.
Background: We previously developed a prediction score for MRI-quantified abdominal visceral adipose tissue (VAT) based on concurrent measurements of height, body mass index (BMI), and nine blood biomarkers, for optimal performance in five racial/ethnic groups. Here we evaluated the VAT score for prediction of future VAT and examined if enhancement with additional biomarkers, lifestyle behavior information, and medical history improves the prediction.
Methods: We examined 500 participants from the Multiethnic Cohort (MEC) with detailed data (age 50-66) collected 10 years prior to their MRI assessment of VAT.
Article Synopsis
- * The newly developed multi-ancestry PRS showed a strong correlation with LUAD risk, indicating that individuals in the highest PRS percentile had significantly increased risk compared to those in the lowest.
- * Findings suggest that those in the highest risk category have a lifetime risk of about 6.69%, and they reach the average population's 10-year risk for LUAD by age 41, highlighting the importance of multi-ancestry PRS for better risk assessment in this group.
Article Synopsis
- Colorectal cancer (CRC) is a widely increasing disease linked to high body mass index (BMI), but the exact biological processes connecting these two factors are not well understood.
- The study employed Mendelian randomization to explore various biomarkers and lifestyle factors potentially mediating the impact of BMI on CRC risk, focusing on elements like inflammation, insulin levels, and physical activity.
- The findings indicated that higher genetically predicted BMI correlates with increased CRC risk, with evidence suggesting that the relationship might be partly mediated by plasma IGF1, while smoking and physical activity appear to complicate the association rather than mediate it.
Breast cancer survivors have an increased risk of developing second primary cancers, yet risks by race and ethnicity have not been comprehensively described. We evaluated second primary cancer risks among 717,335 women diagnosed with first primary breast cancer (aged 20-84 years and survived ≥1-year) in the SEER registries using standardized incidence ratios (SIRs; observed/expected). SIRs were estimated by race and ethnicity compared with the racial- and ethnic-matched general population, and further stratified by clinical characteristics of the index breast cancer.
View Article and Find Full Text PDFIt remains unknown whether adiposity subtypes are differentially associated with colorectal cancer (CRC). To move beyond single-trait anthropometric indicators, we derived four multi-trait body shape phenotypes reflecting adiposity subtypes from principal components analysis on body mass index, height, weight, waist-to-hip ratio, and waist and hip circumference. A generally obese (PC1) and a tall, centrally obese (PC3) body shape were both positively associated with CRC risk in observational analyses in 329,828 UK Biobank participants (3728 cases).
View Article and Find Full Text PDFExposure to outdoor ambient air toxics and risk of breast cancer: The multiethnic cohort.
Int J Hyg Environ Health
June 2024
Background: A growing literature has reported associations between traffic-related air pollution and breast cancer, however there are fewer investigations into specific ambient agents and any putative risk of breast cancer development, particularly studies occurring in populations residing in higher pollution areas such as Los Angeles.
Objectives: To estimate breast cancer risks related to ambient air toxics exposure at residential addresses.
Methods: We examined the relationships between ambient air toxics and breast cancer risk in the Multiethnic Cohort among 48,665 California female participants followed for cancer from 2003 through 2013.
Objective: The US 5-year survival rate after thyroid cancer (TC) diagnosis is over 95%. Our aim was to investigate survival differences by sex and race and ethnicity in a multiethnic US population.
Design: In the Multiethnic Cohort (MEC) study, a total of 605 incident TC cases were identified by linkage to HI and CA statewide cancer registries.
Article Synopsis
- The study analyzed the age at lung cancer diagnosis and sex differences in individuals who never smoked, involving 33,793 participants from various regions including East Asia, the US, and the UK.
- Results showed that in Chinese individuals, females were diagnosed at a younger age than males, with significant differences recorded in several locations, while patterns in other racial groups were inconsistent.
- The findings suggest that there are notable sex differences in the age of diagnosis for lung cancer among non-smokers, highlighting the need for further research in this area.
Objective: Despite advances in incorporating diversity and structural competency into medical education curriculum, there is limited curriculum for public health research professionals. We developed and implemented a four-part diversity, equity, and inclusion (DEI) training series tailored for academic health research professionals to increase foundational knowledge of core diversity concepts and improve skills.
Methods: We analyzed close- and open-ended attendee survey data to evaluate within- and between-session changes in DEI knowledge and perceived skills.
Association between Airport Ultrafine Particles and Lung Cancer Risk: The Multiethnic Cohort Study.
Cancer Epidemiol Biomarkers Prev
May 2024
Background: Ultrafine particles (UFP) are unregulated air pollutants abundant in aviation exhaust. Emerging evidence suggests that UFPs may impact lung health due to their high surface area-to-mass ratio and deep penetration into airways. This study aimed to assess long-term exposure to airport-related UFPs and lung cancer incidence in a multiethnic population in Los Angeles County.
View Article and Find Full Text PDFArticle Synopsis
- Obesity is linked to various types of colorectal cancer (CRC), but the strength and cause of these links are not fully understood.
- By using Mendelian randomization, researchers studied how body size traits like BMI, waist circumference, and body fat percentage affect risks for different CRC subtypes.
- Results showed that higher BMI and body fat significantly increased the risks for serrated and alternate CRC pathways (Jass types 1, 2, and 3), while associations with the traditional pathway (Jass type 4) were weaker.
Objective: Neighborhood characteristics have been shown to influence lifestyle behaviors. Here we characterized alcohol outlet density in Los Angeles County, CA, and Hawaii and assessed the association of alcohol outlet density with self-reported alcohol intake in the Multiethnic Cohort.
Method: Participants ( = 178,977) had their addresses geocoded at cohort entry (1993-1996) and appended to block group-level alcohol outlet densities (on- and off-premises).
Background: Type 2 diabetes is associated with higher risk of several cancer types. However, the biological intermediates driving this relationship are not fully understood. As novel interventions for treating and managing type 2 diabetes become increasingly available, whether they also disrupt the pathways leading to increased cancer risk is currently unknown.
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