Polygenic score distribution differences across European ancestry populations: implications for breast cancer risk prediction.

Background: The 313-variant polygenic risk score (PRS) provides a promising tool for clinical breast cancer risk prediction. However, evaluation of the PRS across different European populations which could influence risk estimation has not been performed.

Methods: We explored the distribution of PRS across European populations using genotype data from 94,072 females without breast cancer diagnosis, of European-ancestry from 21 countries participating in the Breast Cancer Association Consortium (BCAC) and 223,316 females without breast cancer diagnosis from the UK Biobank.

Endocrine therapy initiation among women diagnosed with ductal carcinoma in situ from 2001 to 2018.

Purpose: Trials demonstrating benefits of tamoxifen for women with ductal carcinoma in situ (DCIS) were published > 20 years ago; yet subsequent uptake of endocrine therapy was low. We estimated endocrine therapy initiation in women with DCIS between 2001 and 2018 in a community setting, reflecting more recent years of diagnosis than previous studies.

Methods: This retrospective cohort included adult females ≥ 20 years diagnosed with first primary DCIS between 2001 and 2018, followed through 2019, and enrolled in one of three U.

A Historical Survey of Key Epidemiological Studies of Ionizing Radiation Exposure.

In this article we review the history of key epidemiological studies of populations exposed to ionizing radiation. We highlight historical and recent findings regarding radiation-associated risks for incidence and mortality of cancer and non-cancer outcomes with emphasis on study design and methods of exposure assessment and dose estimation along with brief consideration of sources of bias for a few of the more important studies. We examine the findings from the epidemiological studies of the Japanese atomic bomb survivors, persons exposed to radiation for diagnostic or therapeutic purposes, those exposed to environmental sources including Chornobyl and other reactor accidents, and occupationally exposed cohorts.

Age-Specific Cancer Mortality in the US During the COVID-19 Pandemic, March to December 2020.

Background: It is important to understand the impact of the COVID-19 pandemic on cancer death rates in 2020 in the US. We estimated whether there were larger-than-expected changes in cancer mortality rates from March to December 2020 after accounting for temporal and seasonal patterns using data from January 2011 to February 2020 by cancer type and age.

Methods: We obtained death counts and underlying causes of death by cancer type, month/year (2011-2020), and age group from the National Center for Health Statistics and population estimates from the US Census Bureau.

Long-term cardiovascular disease risk after anthracycline and trastuzumab treatments in US breast cancer survivors.

Background: Although breast cancer survivors are at risk for cardiovascular disease (CVD) from treatment late effects, evidence to inform long-term and age-specific cardiovascular surveillance recommendations is lacking.

Methods: We conducted a retrospective cohort study of 10 211 women diagnosed with first primary unilateral breast cancer in Kaiser Permanente Washington or Colorado (aged 20 years and older, survived ≥1 year). We estimated multivariable adjusted hazard ratios (HRs) for associations between initial chemotherapy regimen type (anthracycline and/or trastuzumab, other chemotherapies, no chemotherapy [referent]) and CVD risk, adjusted for patient characteristics, other treatments, and CVD risk factors.

Second primary cancer risks according to race and ethnicity among U.S. breast cancer survivors.

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.

Disentangling the relationships of body mass index and circulating sex hormone concentrations in mammographic density using Mendelian randomization.

Purpose: Mammographic density phenotypes, adjusted for age and body mass index (BMI), are strong predictors of breast cancer risk. BMI is associated with mammographic density measures, but the role of circulating sex hormone concentrations is less clear. We investigated the relationship between BMI, circulating sex hormone concentrations, and mammographic density phenotypes using Mendelian randomization (MR).

Large-scale genome-wide association study of 398,238 women unveils seven novel loci associated with high-grade serous epithelial ovarian cancer risk.

Background: Nineteen genomic regions have been associated with high-grade serous ovarian cancer (HGSOC). We used data from the Ovarian Cancer Association Consortium (OCAC), Consortium of Investigators of Modifiers of (CIMBA), UK Biobank (UKBB), and FinnGen to identify novel HGSOC susceptibility loci and develop polygenic scores (PGS).

Methods: We analyzed >22 million variants for 398,238 women.

Polygenic risk scores, radiation treatment exposures and subsequent cancer risk in childhood cancer survivors.

Survivors of childhood cancer are at increased risk for subsequent cancers attributable to the late effects of radiotherapy and other treatment exposures; thus, further understanding of the impact of genetic predisposition on risk is needed. Combining genotype data for 11,220 5-year survivors from the Childhood Cancer Survivor Study and the St Jude Lifetime Cohort, we found that cancer-specific polygenic risk scores (PRSs) derived from general population, genome-wide association study, cancer loci identified survivors of European ancestry at increased risk of subsequent basal cell carcinoma (odds ratio per s.d.

Differences in polygenic score distributions in European ancestry populations: implications for breast cancer risk prediction.

The 313-variant polygenic risk score (PRS) provides a promising tool for breast cancer risk prediction. However, evaluation of the PRS across different European populations which could influence risk estimation has not been performed. Here, we explored the distribution of PRS across European populations using genotype data from 94,072 females without breast cancer, of European-ancestry from 21 countries participating in the Breast Cancer Association Consortium (BCAC) and 225,105 female participants from the UK Biobank.

BMI and breast cancer risk around age at menopause.

Background: A high body mass index (BMI, kg/m) is associated with decreased risk of breast cancer before menopause, but increased risk after menopause. Exactly when this reversal occurs in relation to menopause is unclear. Locating that change point could provide insight into the role of adiposity in breast cancer etiology.

The Pediatric Proton and Photon Therapy Comparison Cohort: Study Design for a Multicenter Retrospective Cohort to Investigate Subsequent Cancers After Pediatric Radiation Therapy.

Purpose: The physical properties of protons lower doses to surrounding normal tissues compared with photons, potentially reducing acute and long-term adverse effects, including subsequent cancers. The magnitude of benefit is uncertain, however, and currently based largely on modeling studies. Despite the paucity of directly comparative data, the number of proton centers and patients are expanding exponentially.

Risk of hematological malignancies from CT radiation exposure in children, adolescents and young adults.

Over one million European children undergo computed tomography (CT) scans annually. Although moderate- to high-dose ionizing radiation exposure is an established risk factor for hematological malignancies, risks at CT examination dose levels remain uncertain. Here we followed up a multinational cohort (EPI-CT) of 948,174 individuals who underwent CT examinations before age 22 years in nine European countries.

Quest markup for developing FAIR questionnaire modules for epidemiologic studies.

Background: Online questionnaires are commonly used to collect information from participants in epidemiological studies. This requires building questionnaires using machine-readable formats that can be delivered to study participants using web-based technologies such as progressive web applications. However, the paucity of open-source markup standards with support for complex logic make collaborative development of web-based questionnaire modules difficult.

Radiation exposure and leukaemia risk among cohorts of persons exposed to low and moderate doses of external ionising radiation in childhood.

Background: Many high-dose groups demonstrate increased leukaemia risks, with risk greatest following childhood exposure; risks at low/moderate doses are less clear.

Methods: We conducted a pooled analysis of the major radiation-associated leukaemias (acute myeloid leukaemia (AML) with/without the inclusion of myelodysplastic syndrome (MDS), chronic myeloid leukaemia (CML), acute lymphoblastic leukaemia (ALL)) in ten childhood-exposed groups, including Japanese atomic bomb survivors, four therapeutically irradiated and five diagnostically exposed cohorts, a mixture of incidence and mortality data. Relative/absolute risk Poisson regression models were fitted.