Risk factors and health behaviors associated with loneliness among cancer survivors during the COVID-19 pandemic

Loneliness may exacerbate poor health outcomes particularly among cancer survivors during the COVID-19 pandemic. Little is known about the risk factors of loneliness among cancer survivors. We evaluated the risk factors of loneliness in the context of COVID-19 pandemic-related prevention behaviors and lifestyle/psychosocial factors among cancer survivors. Cancer survivors (n = 1471) seen at Huntsman Cancer Institute completed a survey between August-September 2020 evaluating health behaviors, medical care, and psychosocial factors including loneliness during COVID-19 pandemic. Participants were classified into two groups: 'lonely' (sometimes, usually, or always felt lonely in past month) and 'non-lonely' (never or rarely felt lonely in past month). 33% of cancer survivors reported feeling lonely in the past month. Multivariable logistic regression showed female sex, not living with a spouse/partner, poor health status, COVID-19 pandemic-associated lifestyle factors including increased alcohol consumption and marijuana/CBD oil use, and psychosocial stressors such as disruptions in daily life, less social interaction, and higher perceived stress and financial stress were associated with feeling lonely as compared to being non-lonely (all p < 0.05). A significant proportion of participants reported loneliness, which is a serious health risk among vulnerable populations, particularly cancer survivors. Modifiable risk factors such as unhealthy lifestyle behaviors and psychosocial stress were associated with loneliness. These results highlight the need to screen for unhealthy lifestyle factors and psychosocial stressors to identify cancer survivors at increased risk of loneliness and to develop effective management strategies.

Age-related differences in employment, insurance, and financial hardship among colorectal cancer patients: a report from the ColoCare Study

PURPOSE

Employment and financial hardships are common issues for working-age colorectal cancer patients. We surveyed colorectal cancer survivors to investigate employment, insurance, and financial outcomes by age at diagnosis.

METHODS

Cross-sectional survey of six ColoCare Study sites regarding employment, insurance, and financial hardship outcomes. Eligible participants were 1 to 5 years from colorectal cancer diagnosis. Diagnosis age (18-49, 50-64, 65+ years) with outcomes of interest were compared using chi-square and t-tests. Multivariable logistic and Poisson regressions were fit to examine association of demographic factors with any material/psychological hardship (yes/no) and the count of hardships.

RESULTS

N = 202 participants completed the survey (age: 18-49 (n = 42, 20.8%), 50-64 (n = 79, 39.1%), 65+ (n = 81, 40.1%)). Most diagnosed age < 65 worked at diagnosis (18-49: 83%; 50-64: 64%; 65+ : 14%, p < 0.001) and continued working after diagnosis (18-49: 76%; 50-64: 59%; 65+ : 13%; p < 0.001). Participants age 18-49 reported cancer-related difficulties with mental (81.3%) and physical (89%) tasks at work more than those working in the older age groups (45%-61%). In regression models, among those reporting any hardship, the rates of material and psychological hardships were higher among those age 18-64 (Incidence Rate Ratios (IRR) range 1.5-2.3 vs. age 65+) and for those with < college (IRR range 1.3-1.6 vs. college +).

CONCLUSIONS

Younger colorectal cancer patients are more likely to work after a cancer diagnosis and during cancer treatment, but report higher levels of financial hardship than older patients.

IMPLICATIONS FOR CANCER SURVIVORS

Younger colorectal cancer patients may encounter financial hardship, thus may feel a need to work during and after treatment.

Two genome-wide interaction loci modify the association of nonsteroidal anti-inflammatory drugs with colorectal cancer

Regular, long-term aspirin use may act synergistically with genetic variants, particularly those in mechanistically relevant pathways, to confer a protective effect on colorectal cancer (CRC) risk. We leveraged pooled data from 52 clinical trial, cohort, and case-control studies that included 30,806 CRC cases and 41,861 controls of European ancestry to conduct a genome-wide interaction scan between regular aspirin/nonsteroidal anti-inflammatory drug (NSAID) use and imputed genetic variants. After adjusting for multiple comparisons, we identified statistically significant interactions between regular aspirin/NSAID use and variants in 6q24.1 (top hit rs72833769), which has evidence of influencing expression of TBC1D7 (a subunit of the TSC1-TSC2 complex, a key regulator of MTOR activity), and variants in 5p13.1 (top hit rs350047), which is associated with expression of PTGER4 (codes a cell surface receptor directly involved in the mode of action of aspirin). Genetic variants with functional impact may modulate the chemopreventive effect of regular aspirin use, and our study identifies putative previously unidentified targets for additional mechanistic interrogation.

Longitudinal associations of plasma kynurenines and ratios with fatigue and quality of life in colorectal cancer survivors up to 12 months post-treatment

Fatigue is prevalent in colorectal cancer (CRC) survivors, impacting their health-related quality of life (HRQoL). Inflammation-induced activation of the kynurenine pathway may play a role in cancer-related fatigue and HRQoL, but evidence is scarce. Therefore, we aimed to investigate longitudinal associations of plasma tryptophan, kynurenines, and ratios with fatigue and HRQoL in CRC survivors up to 12 months post-treatment. Repeated measurements at 6 weeks, 6 months, and 12 months post-treatment were performed in 249 stage I-III CRC survivors. Plasma tryptophan and eight kynurenines were analyzed using liquid chromatography-tandem mass spectrometry (LC/MS-MS). Fatigue and HRQoL outcomes were evaluated using validated questionnaires. Confounder-adjusted linear mixed models were conducted to analyze longitudinal associations, with false discovery rate (FDR) correction. Higher tryptophan (Trp), kynurenic acid (KA), and xanthurenic acid (XA) concentrations, as well as a higher kynurenic acid-to-quinolinic acid ratio (KA/QA), were associated with less fatigue and better functioning, while a higher kynurenine-to-tryptophan ratio (KTR) and 3-hydroxykynurenine ratio (HKr) were associated with more fatigue and worse functioning. Finally, higher KA and XA concentrations and a higher KA/QA ratio were associated with a higher overall HRQoL summary score, while a higher HKr was associated with a lower overall HRQoL summary score. In conclusion, we observed that tryptophan and several kynurenines were longitudinally associated with fatigue and HRQoL in CRC survivors up to 12 months post-treatment. Future research is needed to validate our findings and explore the potential of the kynurenine pathway as intervention target for reducing fatigue and enhancing HRQoL after CRC treatment.

Genome-wide interaction study of dietary intake of fibre, fruits, and vegetables with risk of colorectal cancer

BACKGROUND

Consumption of fibre, fruits and vegetables have been linked with lower colorectal cancer (CRC) risk. A genome-wide gene-environment (G × E) analysis was performed to test whether genetic variants modify these associations.

METHODS

A pooled sample of 45 studies including up to 69,734 participants (cases: 29,896; controls: 39,838) of European ancestry were included. To identify G × E interactions, we used the traditional 1--degree-of-freedom (DF) G × E test and to improve power a 2-step procedure and a 3DF joint test that investigates the association between a genetic variant and dietary exposure, CRC risk and G × E interaction simultaneously.

FINDINGS

The 3-DF joint test revealed two significant loci with p-value <5 × 10-8. Rs4730274 close to the SLC26A3 gene showed an association with fibre (p-value: 2.4 × 10-3) and G × fibre interaction with CRC (OR per quartile of fibre increase = 0.87, 0.80, and 0.75 for CC, TC, and TT genotype, respectively; G × E p-value: 1.8 × 10-7). Rs1620977 in the NEGR1 gene showed an association with fruit intake (p-value: 1.0 × 10-8) and G × fruit interaction with CRC (OR per quartile of fruit increase = 0.75, 0.65, and 0.56 for AA, AG, and GG genotype, respectively; G × E -p-value: 0.029).

INTERPRETATION

We identified 2 loci associated with fibre and fruit intake that also modify the association of these dietary factors with CRC risk. Potential mechanisms include chronic inflammatory intestinal disorders, and gut function. However, further studies are needed for mechanistic validation and replication of findings.

FUNDING

National Institutes of Health, National Cancer Institute. Full funding details for the individual consortia are provided in acknowledgments.

The role of area deprivation index in health care disruptions among cancer survivors during the SARS-CoV-2 pandemic

OBJECTIVE

To examine the associations between demographic/medical and geographic factors with follow-up medical care and health-related quality of life (HRQoL) among cancer survivors during the SARS-CoV-2 pandemic.

STUDY DESIGN

Cross-sectional survey.

METHODS

An online survey was sent to cancer survivors between May 2020 and January 2021, exploring their experience with SARS-CoV-2, follow-up care, and HRQoL. PolicyMap was used to geocode home addresses. Both geographic and demographic/medical factors were examined for their associations with SARS-CoV-2 experience, follow-up care, and HRQoL (FACT-G7).

RESULTS

Geographic data were available for 9651 participants. Patients living in the highest area deprivation index (ADI) neighborhoods (most deprived) had higher odds of avoiding in-person general (odds ratio [OR] = 7.20; 95% confidence interval [CI] = 2.79-18.60), cancer (OR = 8.47; 95% CI = 3.73-19.30), and emergency (OR = 14.2; 95% CI = 5.57-36.30) medical care, as well as lower odds of using telemedicine (OR = 0.61; 95% CI = 0.52-0.73) compared to the lowest ADI group. Race/ethnicity was not associated with follow-up care after controlling for ADI. The effect of ADI on HRQoL was generally in the expected direction, with higher ADI being associated with worse HRQoL.

CONCLUSIONS

ADI influenced follow-up medical care more than age, race/ethnicity, or health insurance type. Healthcare providers and institutions should focus on decreasing barriers to in-person and telemedicine health care that disproportionally impact those living in more deprived communities, which are exacerbated by health care disruptions like those caused by the SARS-CoV-2 pandemic.

Fine-mapping analysis including over 254,000 East Asian and European descendants identifies 136 putative colorectal cancer susceptibility genes

Genome-wide association studies (GWAS) have identified more than 200 common genetic variants independently associated with colorectal cancer (CRC) risk, but the causal variants and target genes are mostly unknown. We sought to fine-map all known CRC risk loci using GWAS data from 100,204 cases and 154,587 controls of East Asian and European ancestry. Our stepwise conditional analyses revealed 238 independent association signals of CRC risk, each with a set of credible causal variants (CCVs), of which 28 signals had a single CCV. Our cis-eQTL/mQTL and colocalization analyses using colorectal tissue-specific transcriptome and methylome data separately from 1299 and 321 individuals, along with functional genomic investigation, uncovered 136 putative CRC susceptibility genes, including 56 genes not previously reported. Analyses of single-cell RNA-seq data from colorectal tissues revealed 17 putative CRC susceptibility genes with distinct expression patterns in specific cell types. Analyses of whole exome sequencing data provided additional support for several target genes identified in this study as CRC susceptibility genes. Enrichment analyses of the 136 genes uncover pathways not previously linked to CRC risk. Our study substantially expanded association signals for CRC and provided additional insight into the biological mechanisms underlying CRC development.

Tissue-specific genetic variation suggests distinct molecular pathways between body shape phenotypes and colorectal cancer

It 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). In genome-wide association studies in 460,198 UK Biobank participants, we identified 3414 genetic variants across four body shapes and Mendelian randomization analyses confirmed positive associations of PC1 and PC3 with CRC risk (52,775 cases/45,940 controls from GECCO/CORECT/CCFR). Brain tissue-specific genetic instruments, mapped to PC1 through enrichment analysis, were responsible for the relationship between PC1 and CRC, while the relationship between PC3 and CRC was predominantly driven by adipose tissue-specific genetic instruments. This study suggests distinct putative causal pathways between adiposity subtypes and CRC.

Functional quality of life among newly diagnosed young adult colorectal cancer survivors compared to older adults: results from the ColoCare Study

PURPOSE

Colorectal cancer (CRC) incidence and mortality are increasing among young adults (YAs) aged 18-39. This study compared quality of life (QOL) between YA and older adult CRC survivors in the ColoCare Study.

METHODS

Participants were grouped by age (years) as follows: 18-39 (YA), 40-49, 50-64, and 65 + . Functional QOL (physical, social, role, emotional, cognitive) and global QOL were assessed with the EORTC-QLQ-C30 at enrollment, 3, 6, and 12 months. Average scores were compared between groups over time using longitudinal mixed-effect modeling. Proportions with clinically meaningful QOL impairment were calculated using age-relevant thresholds and compared between groups over time using logistic regression with mixed effects.

RESULTS

Participants (N = 1590) were n = 81 YAs, n = 196 aged 40-49, n = 627 aged 50-64, and n = 686 aged 65 + . Average physical function was better among YAs than participants aged 50-64 (p = 0.010) and 65 + (p < 0.001), and average social function was worse among YAs than aged 65 + (p = 0.046). Relative to YAs, all age groups were less likely to report clinically meaningful social dysfunction (aged 40-49 OR = 0.13, 95%CI = 0.06-0.29; aged 50-64 OR = 0.10, 95%CI = 0.05-0.21; aged 65 + OR = 0.07, 95%CI = 0.04-0.15) and role dysfunction (aged 40-49 OR = 0.36, 95%CI = 0.18-0.75; aged 50-64 OR = 0.41, 95%CI = 0.22-0.78; aged 65 + OR = 0.32, 95%CI = 0.17-0.61). Participants aged 40-49 were also less likely to report physical dysfunction (OR = 0.42, 95%CI = 0.19-0.93).

CONCLUSION

YA CRC survivors reported better physical and worse social function compared to older CRC survivors, and YA CRC survivors were more likely to report clinically meaningful social, role, and physical disfunction. Future work should further investigate QOL using age-relevant benchmarks to inform best practices for CRC survivorship care.

TRIAL REGISTRATION

NCT02328677, registered December 2014.

Creatine supplementation and resistance training to preserve muscle mass and attenuate cancer progression (CREATINE-52): a protocol for a double-blind randomized controlled trial

BACKGROUND

Muscle mass is important for metastatic prostate cancer survival and quality of life (QoL). The backbone of treatment for men with metastatic castration sensitive prostate cancer (mCSPC) is androgen deprivation therapy (ADT) with an androgen signaling inhibitor. ADT is an effective cancer treatment, but it facilitates significant declines in muscle mass and adverse health outcomes important to mCSPC survivors, such as fatigue, and reductions in physical function, independence, insulin sensitivity, and QoL. In non-metastatic CSPC survivors, resistance training (RT) preserves muscle mass and improves these related health outcomes, but the biggest barrier to RT in CSPC survivors of all stages is fatigue. Creatine monohydrate supplementation coupled with RT (Cr + RT) may address this barrier since creatine plays a critical role in energy metabolism. Cr + RT in cancer-free older adults and other clinical populations improves muscle mass and related health outcomes. Evidence also suggests that creatine supplementation can complement cancer treatment. Thus, Cr + RT is a strategy that addresses gaps in survivorship needs of people with mCSPC. The purpose of this parallel, double-blind randomized controlled trial is to test the effects of 52-weeks of Cr + RT compared with placebo (PLA) and RT (PLA + RT) on muscle mass, other related health outcomes, and markers of cancer progression.

METHODS

We will carry out this trial with our team's established, effective, home-based, telehealth RT program in 200 mCSPC survivors receiving ADT, and evaluate outcomes at baseline, 24-, and 52-weeks. RT will occur twice weekly with elastic resistance bands, and an established creatine supplementation protocol will be used for supplementation delivery. Our approach addresses a major facilitator to RT in mCSPC survivors, a home-based RT program, while utilizing a supervised model for safety.

DISCUSSION

Findings will improve delivery of comprehensive survivorship care by providing a multicomponent, patient-centered lifestyle strategy to preserve muscle mass, improve health outcomes, and complement cancer treatment (NCT06112990).

Cost and Utilization Outcomes in Huntsman at Home, a Novel Oncology Hospital at Home Program

OBJECTIVES

In a real-world trial, we previously demonstrated that Huntsman at Home, a novel oncology hospital at home program, was associated with reduced health care utilization and costs. In this study, we sought to understand the impact of Huntsman at Home in specific patient subgroups defined by sex, age, area-level median income, Charlson Comorbidity Index, and current use of systemic anticancer therapy.

DESIGN

Retrospective case-control study of the Huntsman Cancer Institute. Electronic Data Warehouse of patients enrolled in Huntsman at Home between August 2018 through October 2019 vs usual-care patients.

SETTING AND PARTICIPANTS

A total of 169 patients admitted to Huntsman at Home compared with 198 usual-care patients.

METHODS

Five dichotomous subgroups evaluated including sex (female vs male), age (≥65 vs <65), income (≥$78,735 vs <$78,735), Charlson Comorbidity Index (≥2 vs <2), and current systemic anticancer therapy use vs no current systemic anticancer therapy. Groups were compared with patients receiving usual care. Primary outcomes included 30-day costs, hospital length of stay, unplanned hospitalizations, and emergency room visits.

RESULTS

Admission to Huntsman at Home was associated with an overall reduction across all 4 health care cost and utilization outcomes. Outcomes favoring admission to Huntsman at Home achieved statistical significance (P < .05) in at least 2 of the 4 outcomes for each subgroup studied. Of the subgroups that did not achieve statistically significant benefit from Huntsman at Home admission in some outcome categories, none of these subgroups favored usual care.

CONCLUSIONS AND IMPLICATIONS

Admission to Huntsman at Home decreased utilization of unplanned health care and reduced costs across a wide spectrum of patient subgroups, suggesting overall consistent benefit from the service. Hospital at home models should be considered as a means by which the quality and efficiency of care can be maximized for patients with cancer.

Impact of COVID-19-related experiences on health-related quality of life in cancer survivors in the United States

OBJECTIVE

Little evidence exists on the impact of the COVID-19 pandemic on cancer survivors, limiting recommendations to improve health-related quality of life (HRQoL) in this population. We describe survivors' pandemic experiences and examine associations between COVID-19-related exposures, psychosocial experiences, and HRQoL.

METHODS

Between May 2020-April 2021, survivors completed cross-sectional questionnaires capturing COVID-19-related exposures (e.g., exposure to virus, job loss); psychosocial experiences (i.e., COVID-19-related anxiety/depression, disruptions to health care and daily activities/social interactions, satisfaction with providers' response to COVID, financial hardship, perceived benefits of the pandemic, social support, and perceived stress management ability); and HRQoL.

RESULTS

Data were collected from N = 11,325 survivors in the United States. Participants were mostly female (58%), White (89%) and non-Hispanic (88%), and age 63 on average. Breast cancer was the most common diagnosis (23%). Eight percent of participants reported being exposed to COVID-19; 1% tested positive. About 6% of participants lost their jobs, while 24% lost household income. Nearly 30% avoided attending in-person oncology appointments because of the pandemic. Poorer HRQoL was associated with demographic (younger age; female; non-Hispanic White), clinical (Medicare; stage IV disease; hematologic/digestive/respiratory system cancer), and psychosocial factors (low perceived benefits and stress management ability; more disruption to health care and daily activities/social interactions; financial hardship).

CONCLUSIONS

COVID-19-related stressors were associated with various psychosocial experiences in cancer survivors, and these psychosocial experiences were associated with HRQoL above and beyond demographic and clinical factors.

Genome-Wide Gene-Environment Interaction Analyses to Understand the Relationship between Red Meat and Processed Meat Intake and Colorectal Cancer Risk

BACKGROUND

High red meat and/or processed meat consumption are established colorectal cancer risk factors. We conducted a genome-wide gene-environment (GxE) interaction analysis to identify genetic variants that may modify these associations.

METHODS

A pooled sample of 29,842 colorectal cancer cases and 39,635 controls of European ancestry from 27 studies were included. Quantiles for red meat and processed meat intake were constructed from harmonized questionnaire data. Genotyping arrays were imputed to the Haplotype Reference Consortium. Two-step EDGE and joint tests of GxE interaction were utilized in our genome-wide scan.

RESULTS

Meta-analyses confirmed positive associations between increased consumption of red meat and processed meat with colorectal cancer risk [per quartile red meat OR = 1.30; 95% confidence interval (CI) = 1.21-1.41; processed meat OR = 1.40; 95% CI = 1.20-1.63]. Two significant genome-wide GxE interactions for red meat consumption were found. Joint GxE tests revealed the rs4871179 SNP in chromosome 8 (downstream of HAS2); greater than median of consumption ORs = 1.38 (95% CI = 1.29-1.46), 1.20 (95% CI = 1.12-1.27), and 1.07 (95% CI = 0.95-1.19) for CC, CG, and GG, respectively. The two-step EDGE method identified the rs35352860 SNP in chromosome 18 (SMAD7 intron); greater than median of consumption ORs = 1.18 (95% CI = 1.11-1.24), 1.35 (95% CI = 1.26-1.44), and 1.46 (95% CI = 1.26-1.69) for CC, CT, and TT, respectively.

CONCLUSIONS

We propose two novel biomarkers that support the role of meat consumption with an increased risk of colorectal cancer.

IMPACT

The reported GxE interactions may explain the increased risk of colorectal cancer in certain population subgroups.

Relationships Among Physical Activity, Sleep, and Cancer-related Fatigue: Results From the International ColoCare Study

BACKGROUND

Risk factors for cancer-related fatigue are understudied in colorectal cancer.

PURPOSE

This study aimed to address this critical gap in the literature by (a) describing changes in colorectal cancer-related fatigue and health behavior (physical activity, sleep problems) and (b) examining if physical activity and sleep problems predict fatigue trajectories from baseline (approximately at the time of diagnosis), to 6- and 12 months after enrollment.

METHODS

Patients participating in the international ColoCare Study completed self-report measures at baseline (approximately time of diagnosis), 6-, and 12 months assessing physical activity using the International Physical Activity Questionnaire (IPAQ) and fatigue and sleep using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ-C30). Mixed-effect models examined changes in physical activity, sleep problems, and fatigue. Cross-lagged panel models examined bidirectional relationships between physical activity or sleep and fatigue across time.

RESULTS

Colorectal cancer patients (n = 649) had a mean age of 61 ± 13 years. Most were male (59%), non-Hispanic White (91%), diagnosed with Stages III-IV (56%) colon cancer (58%), and treated with surgery (98%). Within-person cross-lagged models indicated higher physical activity at Month 6 was associated with higher fatigue at Month 12 (β = 0.26, p = .016). When stratified by cancer stage (I-II vs. III-IV), the relationship between physical activity at Month 6 and fatigue at Month 12 existed only for patients with advanced cancer (Stages III and IV, β = 0.43, p = .035). Cross-lagged associations for sleep and fatigue from baseline to Month 6 were only observed in patients with Stages III or IV cancer, however, there was a clear cross-sectional association between sleep problems and fatigue at baseline and Month 6.

CONCLUSIONS

Within-person and cross-lagged association models suggest fatiguability may become increasingly problematic for patients with advanced colorectal cancer the first year after diagnosis. In addition, sleep problems were consistently associated with higher fatigue in the first year, regardless of cancer stage.

TRIAL REGISTRATION

The international ColoCare Study was registered on clinicaltrials.gov, NCT02328677, in December 2014.

A Bioinformatics Tool for Identifying Intratumoral Microbes from the ORIEN Dataset

Evidence supports significant interactions among microbes, immune cells, and tumor cells in at least 10%-20% of human cancers, emphasizing the importance of further investigating these complex relationships. However, the implications and significance of tumor-related microbes remain largely unknown. Studies have demonstrated the critical roles of host microbes in cancer prevention and treatment responses. Understanding interactions between host microbes and cancer can drive cancer diagnosis and microbial therapeutics (bugs as drugs). Computational identification of cancer-specific microbes and their associations is still challenging due to the high dimensionality and high sparsity of intratumoral microbiome data, which requires large datasets containing sufficient event observations to identify relationships, and the interactions within microbial communities, the heterogeneity in microbial composition, and other confounding effects that can lead to spurious associations. To solve these issues, we present a bioinformatics tool, microbial graph attention (MEGA), to identify the microbes most strongly associated with 12 cancer types. We demonstrate its utility on a dataset from a consortium of nine cancer centers in the Oncology Research Information Exchange Network. This package has three unique features: species-sample relations are represented in a heterogeneous graph and learned by a graph attention network; it incorporates metabolic and phylogenetic information to reflect intricate relationships within microbial communities; and it provides multiple functionalities for association interpretations and visualizations. We analyzed 2,704 tumor RNA sequencing samples and MEGA interpreted the tissue-resident microbial signatures of each of 12 cancer types. MEGA can effectively identify cancer-associated microbial signatures and refine their interactions with tumors.

SIGNIFICANCE

Studying the tumor microbiome in high-throughput sequencing data is challenging because of the extremely sparse data matrices, heterogeneity, and high likelihood of contamination. We present a new deep learning tool, MEGA, to refine the organisms that interact with tumors.

Intake and biomarkers of folate and folic acid as determinants of chemotherapy-induced toxicities in patients with colorectal cancer: a cohort study

BACKGROUND

Capecitabine is an oral chemotherapeutic drug showing antitumor activity through inhibition of thymidylate synthase, an enzyme involved in folate metabolism. There are concerns about the high intake of certain vitamins, and specifically folate, during chemotherapy with capecitabine. Whether folate or folic acid, the synthetic variant of the vitamin, impact treatment toxicity remains unclear.

OBJECTIVE

We studied associations between intake and biomarkers of folate as well as folic acid and toxicities in patients with colorectal cancer (CRC) receiving capecitabine.

METHODS

Within the prospective COLON (Colorectal cancer: Longitudinal, Observational study on Nutritional and lifestyle factors that influence recurrence, survival, and quality of life) cohort, 290 patients with stage II to III CRC receiving capecitabine were identified. Dietary and supplemental intake of folate and folic acid were assessed at diagnosis and during chemotherapy using questionnaires (available for 280 patients). Plasma folate and folic acid levels were determined by liquid chromatography tandem mass spectrometry (LC-MS/MS) and were available for 212 patients. Toxicities were defined as toxicity-related modifications of treatment, including dose reductions, regimen switches, and early discontinuation. Associations of intake and biomarkers of folate and folic acid with toxicities were determined using Cox proportional hazards regression adjusted for age and sex.

RESULTS

In total, 153 (53%) patients experienced toxicities leading to modification of capecitabine treatment. Folate intake and plasma folate levels were not associated with risk of toxicities. However, use of folic acid-containing supplements during treatment (hazard ratio (HR) 1.81 and 95% confidence interval (CI) 1.15-2.85) and presence of folic acid in plasma at diagnosis (HR 2.09, 95% CI: 1.24, 3.52) and during treatment (HR 2.31, 95% CI: 1.29, 4.13) were associated with an increased risk of toxicities.

CONCLUSIONS

This study suggests a potential association between folic acid and capecitabine-induced toxicities, providing a rationale to study diet-drug interactions and raise further awareness of the use of dietary supplements during oncological treatment.

CLINICAL TRIAL DETAILS

This trial was registered at clinicaltrials.gov as NCT03191110.

Observational and genetic associations between cardiorespiratory fitness and cancer: a UK Biobank and international consortia study

BACKGROUND

The association of fitness with cancer risk is not clear.

METHODS

We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of lung, colorectal, endometrial, breast, and prostate cancer in a subset of UK Biobank participants who completed a submaximal fitness test in 2009-12 (N = 72,572). We also investigated relationships using two-sample Mendelian randomisation (MR), odds ratios (ORs) were estimated using the inverse-variance weighted method.

RESULTS

After a median of 11 years of follow-up, 4290 cancers of interest were diagnosed. A 3.5 ml O2⋅min-1⋅kg-1 total-body mass increase in fitness (equivalent to 1 metabolic equivalent of task (MET), approximately 0.5 standard deviation (SD)) was associated with lower risks of endometrial (HR = 0.81, 95% CI: 0.73-0.89), colorectal (0.94, 0.90-0.99), and breast cancer (0.96, 0.92-0.99). In MR analyses, a 0.5 SD increase in genetically predicted O2⋅min-1⋅kg-1 fat-free mass was associated with a lower risk of breast cancer (OR = 0.92, 95% CI: 0.86-0.98). After adjusting for adiposity, both the observational and genetic associations were attenuated.

DISCUSSION

Higher fitness levels may reduce risks of endometrial, colorectal, and breast cancer, though relationships with adiposity are complex and may mediate these relationships. Increasing fitness, including via changes in body composition, may be an effective strategy for cancer prevention.

Development and initial psychometric evaluation of a COVID-related psychosocial experiences questionnaire for cancer survivors

BACKGROUND

Cancer survivors are at elevated risk of psychological problems related to COVID-19, yet no published measure adequately assesses their psychosocial experiences during the pandemic.

PURPOSE

Describe the development and factor structure of a comprehensive, self-report measure (COVID-19 Practical and Psychosocial Experiences questionnaire [COVID-PPE]) assessing the pandemic's impact on US cancer survivors.

METHODS

The sample (n = 10,584) was divided into three groups to assess COVID-PPE factor structure by conducting: (1) initial calibration/exploratory analysis of the factor structure of 37 items (n = 5070), (2) confirmatory factor analysis of the best-fitting model (36 items after item removal; n = 5140), and (3) post-hoc confirmatory analysis with an additional six items not collected in the first two groups (42 items; n = 374).

RESULTS

The final COVID-PPE was divided into two sets of subscales, conceptualized as Risk Factors and Protective Factors. The five Risk Factors subscales were labeled Anxiety Symptoms, Depression Symptoms, Health Care Disruptions, Disruptions to Daily Activities and Social Interactions, and Financial Hardship. The four Protective Factors subscales were labeled Perceived Benefits, Provider Satisfaction, Perceived Stress Management Skills, and Social Support. Internal consistency was acceptable for seven subscales (αs = 0.726-0.895; ωs = 0.802-0.895) but poor or questionable for the remaining two subscales (αs = 0.599-0.681; ωs = 0.586-0.692).

CONCLUSIONS

To our knowledge, this is the first published self-report measure comprehensively capturing psychosocial impact-both positive and negative-of the pandemic on cancer survivors. Future work should evaluate predictive utility of COVID-PPE subscales, particularly as the pandemic evolves, which may inform recommendations for cancer survivors and facilitate identification of survivors most in need of intervention.

Genome-wide interaction analysis of folate for colorectal cancer risk

BACKGROUND

Epidemiological and experimental evidence suggests that higher folate intake is associated with decreased colorectal cancer (CRC) risk; however, the mechanisms underlying this relationship are not fully understood. Genetic variation that may have a direct or indirect impact on folate metabolism can provide insights into folate's role in CRC.

OBJECTIVES

Our aim was to perform a genome-wide interaction analysis to identify genetic variants that may modify the association of folate on CRC risk.

METHODS

We applied traditional case-control logistic regression, joint 3-degree of freedom, and a 2-step weighted hypothesis approach to test the interactions of common variants (allele frequency >1%) across the genome and dietary folate, folic acid supplement use, and total folate in relation to risk of CRC in 30,550 cases and 42,336 controls from 51 studies from 3 genetic consortia (CCFR, CORECT, GECCO).

RESULTS

Inverse associations of dietary, total folate, and folic acid supplement with CRC were found (odds ratio [OR]: 0.93; 95% confidence interval [CI]: 0.90, 0.96; and 0.91; 95% CI: 0.89, 0.94 per quartile higher intake, and 0.82 (95% CI: 0.78, 0.88) for users compared with nonusers, respectively). Interactions (P-interaction < 5×10-8) of folic acid supplement and variants in the 3p25.2 locus (in the region of Synapsin II [SYN2]/tissue inhibitor of metalloproteinase 4 [TIMP4]) were found using traditional interaction analysis, with variant rs150924902 (located upstream to SYN2) showing the strongest interaction. In stratified analyses by rs150924902 genotypes, folate supplementation was associated with decreased CRC risk among those carrying the TT genotype (OR: 0.82; 95% CI: 0.79, 0.86) but increased CRC risk among those carrying the TA genotype (OR: 1.63; 95% CI: 1.29, 2.05), suggesting a qualitative interaction (P-interaction = 1.4×10-8). No interactions were observed for dietary and total folate.

CONCLUSIONS

Variation in 3p25.2 locus may modify the association of folate supplement with CRC risk. Experimental studies and studies incorporating other relevant omics data are warranted to validate this finding.

Combining Asian and European genome-wide association studies of colorectal cancer improves risk prediction across racial and ethnic populations

Polygenic risk scores (PRS) have great potential to guide precision colorectal cancer (CRC) prevention by identifying those at higher risk to undertake targeted screening. However, current PRS using European ancestry data have sub-optimal performance in non-European ancestry populations, limiting their utility among these populations. Towards addressing this deficiency, we expand PRS development for CRC by incorporating Asian ancestry data (21,731 cases; 47,444 controls) into European ancestry training datasets (78,473 cases; 107,143 controls). The AUC estimates (95% CI) of PRS are 0.63(0.62-0.64), 0.59(0.57-0.61), 0.62(0.60-0.63), and 0.65(0.63-0.66) in independent datasets including 1681-3651 cases and 8696-115,105 controls of Asian, Black/African American, Latinx/Hispanic, and non-Hispanic White, respectively. They are significantly better than the European-centric PRS in all four major US racial and ethnic groups (p-values < 0.05). Further inclusion of non-European ancestry populations, especially Black/African American and Latinx/Hispanic, is needed to improve the risk prediction and enhance equity in applying PRS in clinical practice.

Trajectories and risk factors of fatigue following colorectal cancer diagnosis

AIM

This study sought to identify groups of colorectal cancer patients based upon trajectories of fatigue and examine how demographic, clinical and behavioural risk factors differentiate these groups.

METHOD

Patients were from six cancer centres in the United States and Germany. Fatigue was measured using the fatigue subscale of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) at five time points (baseline/enrolment and 3, 6, 12 and 24 months after diagnosis). Piecewise growth mixture models identified latent trajectories of fatigue. Logistic regression models examined differences in demographic, clinical and behavioural characteristics between fatigue trajectory groups.

RESULTS

Among 1615 participants (57% men, 86% non-Hispanic White, mean age 61 ± 13 years at diagnosis), three distinct groups were identified. In the high fatigue group (36%), fatigue significantly increased in the first 6 months after diagnosis and then showed statistically and clinically significant improvement from 6 to 24 months (P values < 0.01). Throughout the study period, average fatigue met or exceeded cutoffs for clinical significance. In the moderate (34%) and low (30%) fatigue groups, fatigue levels remained below or near population norms across the study period. Patients who were diagnosed with Stage II-IV disease and/or current smokers were more likely to be in the high fatigue than in the moderate fatigue group (P values < 0.05).

CONCLUSION

A large proportion of colorectal cancer patients experienced sustained fatigue after initiation of cancer treatment. Patients with high fatigue at the time of diagnosis may benefit from early supportive care.

Elevated EVL Methylation Level in the Normal Colon Mucosa Is a Potential Risk Biomarker for Developing Recurrent Adenomas

BACKGROUND

Individuals with adenomatous colorectal polyps undergo repeated colonoscopy surveillance to identify and remove metachronous adenomas. However, many patients with adenomas do not develop recurrent adenomas. Better methods to evaluate who benefits from increased surveillance are needed. We evaluated the use of altered EVL methylation as a potential biomarker for risk of recurrent adenomas.

METHODS

Patients with ≥1 colonoscopy had EVL methylation (mEVL) measured with an ultra-accurate methylation-specific droplet digital PCR assay on normal colon mucosa. The association between EVL methylation levels and adenoma or colorectal cancer was evaluated using three case/control definitions in three models: unadjusted (model 1), adjusting for baseline characteristics (model 2), and an adjusted model excluding patients with colorectal cancer at baseline (model 3).

RESULTS

Between 2001 and 2020, 136 patients were included; 74 healthy patients and 62 patients with a history of colorectal cancer. Older age, never smoking, and baseline colorectal cancer were associated with higher levels of mEVL (P ≤ 0.05). Each log base 10 difference in mEVL was associated with an increased risk of adenoma(s) or cancer at/after baseline for model 1 [OR, 2.64; 95% confidence interval (CI), 1.09-6.36], and adenoma(s) or cancer after baseline for models 1 (OR, 2.01; 95% CI, 1.04-3.90) and model 2 (OR, 3.17; 95% CI, 1.30-7.72).

CONCLUSIONS

Our results suggest that EVL methylation level detected in the normal colon mucosa has the potential to be a biomarker for monitoring the risk for recurrent adenomas.

IMPACT

These findings support the potential utility of EVL methylation for improving the accuracy for assigning risk for recurrent colorectal adenomas and cancer.

Risk Stratification for Early-onset Colorectal Cancer Screening: Are We Ready for Implementation?

Early-onset colorectal cancer (EOCRC) is increasing at alarming rates and identifying risk factors is a high priority. There is a need to develop risk stratification approaches for colorectal cancer screening among younger populations. Although there is a growing body of evidence identifying risk factors for EOCRC, including the report by Imperiale and colleagues in this issue, risk stratification for EOCRC screening has not been implemented into practice. This publication highlights how essential it is to bring research findings into practice and bridge the gaps between developing risk prediction modeling in epidemiology and implementation science. While encouraging, we are still a long way off from having a clinically applicable risk prediction tool. See related article by Imperiale et al., p. 513.

Probing the diabetes and colorectal cancer relationship using gene - environment interaction analyses

BACKGROUND

Diabetes is an established risk factor for colorectal cancer. However, the mechanisms underlying this relationship still require investigation and it is not known if the association is modified by genetic variants. To address these questions, we undertook a genome-wide gene-environment interaction analysis.

METHODS

We used data from 3 genetic consortia (CCFR, CORECT, GECCO; 31,318 colorectal cancer cases/41,499 controls) and undertook genome-wide gene-environment interaction analyses with colorectal cancer risk, including interaction tests of genetics(G)xdiabetes (1-degree of freedom; d.f.) and joint testing of Gxdiabetes, G-colorectal cancer association (2-d.f. joint test) and G-diabetes correlation (3-d.f. joint test).

RESULTS

Based on the joint tests, we found that the association of diabetes with colorectal cancer risk is modified by loci on chromosomes 8q24.11 (rs3802177, SLC30A8 - ORAA: 1.62, 95% CI: 1.34-1.96; ORAG: 1.41, 95% CI: 1.30-1.54; ORGG: 1.22, 95% CI: 1.13-1.31; p-value3-d.f.: 5.46 × 10-11) and 13q14.13 (rs9526201, LRCH1 - ORGG: 2.11, 95% CI: 1.56-2.83; ORGA: 1.52, 95% CI: 1.38-1.68; ORAA: 1.13, 95% CI: 1.06-1.21; p-value2-d.f.: 7.84 × 10-09).

DISCUSSION

These results suggest that variation in genes related to insulin signaling (SLC30A8) and immune function (LRCH1) may modify the association of diabetes with colorectal cancer risk and provide novel insights into the biology underlying the diabetes and colorectal cancer relationship.

A Genetic Locus within the FMN1/GREM1 Gene Region Interacts with Body Mass Index in Colorectal Cancer Risk

Colorectal cancer risk can be impacted by genetic, environmental, and lifestyle factors, including diet and obesity. Gene-environment interactions (G × E) can provide biological insights into the effects of obesity on colorectal cancer risk. Here, we assessed potential genome-wide G × E interactions between body mass index (BMI) and common SNPs for colorectal cancer risk using data from 36,415 colorectal cancer cases and 48,451 controls from three international colorectal cancer consortia (CCFR, CORECT, and GECCO). The G × E tests included the conventional logistic regression using multiplicative terms (one degree of freedom, 1DF test), the two-step EDGE method, and the joint 3DF test, each of which is powerful for detecting G × E interactions under specific conditions. BMI was associated with higher colorectal cancer risk. The two-step approach revealed a statistically significant G×BMI interaction located within the Formin 1/Gremlin 1 (FMN1/GREM1) gene region (rs58349661). This SNP was also identified by the 3DF test, with a suggestive statistical significance in the 1DF test. Among participants with the CC genotype of rs58349661, overweight and obesity categories were associated with higher colorectal cancer risk, whereas null associations were observed across BMI categories in those with the TT genotype. Using data from three large international consortia, this study discovered a locus in the FMN1/GREM1 gene region that interacts with BMI on the association with colorectal cancer risk. Further studies should examine the potential mechanisms through which this locus modifies the etiologic link between obesity and colorectal cancer.

SIGNIFICANCE

This gene-environment interaction analysis revealed a genetic locus in FMN1/GREM1 that interacts with body mass index in colorectal cancer risk, suggesting potential implications for precision prevention strategies.