Cachexia: A systemic consequence of progressive, unresolved disease.

Cachexia, a systemic wasting condition, is considered a late consequence of diseases, including cancer, organ failure, or infections, and contributes to significant morbidity and mortality. The induction process and mechanistic progression of cachexia are incompletely understood. Refocusing academic efforts away from advanced cachexia to the etiology of cachexia may enable discoveries of new therapeutic approaches. Here, we review drivers, mechanisms, organismal predispositions, evidence for multi-organ interaction, model systems, clinical research, trials, and care provision from early onset to late cachexia. Evidence is emerging that distinct inflammatory, metabolic, and neuro-modulatory drivers can initiate processes that ultimately converge on advanced cachexia.

American Cancer Society nutrition and physical activity guideline for cancer survivors.

The overall 5-year relative survival rate for all cancers combined is now 68%, and there are over 16.9 million survivors in the United States. Evidence from laboratory and observational studies suggests that factors such as diet, physical activity, and obesity may affect risk for recurrence and overall survival after a cancer diagnosis. The purpose of this American Cancer Society guideline is to provide evidence-based, cancer-specific recommendations for anthropometric parameters, physical activity, diet, and alcohol intake for reducing recurrence and cancer-specific and overall mortality. The audiences for this guideline are health care providers caring for cancer survivors as well as cancer survivors and their families. The guideline is intended to serve as a resource for informing American Cancer Society programs, health policy, and the media. Sources of evidence that form the basis of this guideline are systematic literature reviews, meta-analyses, pooled analyses of cohort studies, and large randomized clinical trials published since 2012. Recommendations for nutrition and physical activity during cancer treatment, informed by current practice, large cancer care organizations, and reviews of other expert bodies, are also presented. To provide additional context for the guidelines, the authors also include information on the relationship between health-related behaviors and comorbidities, long-term sequelae and patient-reported outcomes, and health disparities, with attention to enabling survivors' ability to adhere to recommendations. Approaches to meet survivors' needs are addressed as well as clinical care coordination and resources for nutrition and physical activity counseling after a cancer diagnosis.

American Cancer Society guideline for diet and physical activity for cancer prevention.

The American Cancer Society (ACS) publishes the Diet and Physical Activity Guideline to serve as a foundation for its communication, policy, and community strategies and, ultimately, to affect dietary and physical activity patterns among Americans. This guideline is developed by a national panel of experts in cancer research, prevention, epidemiology, public health, and policy, and reflects the most current scientific evidence related to dietary and activity patterns and cancer risk. The ACS guideline focuses on recommendations for individual choices regarding diet and physical activity patterns, but those choices occur within a community context that either facilitates or creates barriers to healthy behaviors. Therefore, this committee presents recommendations for community action to accompany the 4 recommendations for individual choices to reduce cancer risk. These recommendations for community action recognize that a supportive social and physical environment is indispensable if individuals at all levels of society are to have genuine opportunities to choose healthy behaviors. This 2020 ACS guideline is consistent with guidelines from the American Heart Association and the American Diabetes Association for the prevention of coronary heart disease and diabetes as well as for general health promotion, as defined by the 2015 to 2020 Dietary Guidelines for Americans and the 2018 Physical Activity Guidelines for Americans.

Dietary quality and chemotherapy-induced peripheral neuropathy in colon cancer.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a common and dose-limiting chemotoxicity caused by oxaliplatin. This study investigated the relationship between dietary quality and the development of moderate and/or severe CIPN in colon cancer survivors using data from the Focus on Reducing Dose-Limiting Toxicities in Colon Cancer with Resistance Exercise trial (ClinicalTrials.gov identifier NCT03291951). METHODS: Diet quality was collected using a 127-item food-frequency questionnaire and was scored using the Alternative Healthy Eating Index-2010 (AHEI-2010). CIPN was assessed with the Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events at each chemotherapy cycle. The association of dietary quality with time to the first moderate-to-severe (moderate-severe) or severe event of CIPN was estimated using Cox proportional hazards models. Only participants who received oxaliplatin were included in this analysis (n = 132). RESULTS: Seventy-four participants (56.1%) reported moderate-severe CIPN. Higher dietary quality was associated with a significantly decreased risk of moderate-severe CIPN (hazard ratio [HR], 0.96; 95% confidence interval [CI], 0.93-0.99) and severe CIPN (HR, 0.91; 95% CI, 0.85-0.98). Consumption of red and processed meat (HR, 1.78; 95% CI, 1.07-2.83) and sugar-sweetened beverages (HR, 1.33; 95% CI, 1.10-1.59) was associated with an increased risk of moderate-severe CIPN. Consumption of sugar-sweetened beverages also was associated with an increased risk of severe CIPN (HR, 1.57; 95% CI, 1.14-2.18), whereas vegetable consumption was associated with a reduced risk of severe CIPN (HR, 0.29; 95% CI, 0.09-0.73). CONCLUSIONS: Among patients with colon cancer who received oxaliplatin-based chemotherapy, higher baseline dietary quality was associated with a reduced risk of moderate-severe CIPN.

Effect of home-based resistance training on chemotherapy relative dose intensity and tolerability in colon cancer: The FORCE randomized control trial.

BACKGROUND: Many patients with colon cancer cannot fully adhere to postoperative chemotherapy due to dose-limiting toxicities, resulting in lower relative dose intensity (RDI) and potentially compromising overall survival. This study examined whether home-based resistance training (RT) during adjuvant chemotherapy improves RDI and patient-reported toxicities versus usual care (UC) in colon cancer patients. METHODS: Multicenter, randomized control trial (RCT) conducted at community and academic practices. Enrollment of patients receiving postoperative chemotherapy for colon cancer occurred between February 23, 2018, and September 29, 2021; final follow-up was March 21, 2022. Participants were randomized to RT (n = 90) or UC (n = 91) for the duration of chemotherapy. Participants in the RT group engaged in twice weekly home-based progressive RT. At the end of the study, UC was given an online exercise program. RESULTS: Among 181 randomized patients (mean age, 55.2 [SD, 12.8] years, 95 [52.5%] were men), there were no differences in the mean RDI among those in RT (79% [SD, 19%]) and those in UC (82% [SD, 19%]); (mean difference -0.04 [95% confidence interval (CI), -0.09 to 0.02]). Assignment to RT did not significantly reduce the number of moderate/severe symptoms per week across follow-up (relative rate: 0.94 [95% CI, 0.72-1.22]). Additionally, time since randomization did not significantly modify the effect of RT on the overall number of symptoms (p = .06). CONCLUSIONS: Among patients with colon cancer, these results do not support home-based RT as an adjunct to chemotherapy specifically to improve planned treatment intensity.

Alcohol consumption and prognosis and survival in breast cancer survivors: The Pathways Study.

BACKGROUND: The impact of alcohol consumption on breast cancer (BC) prognosis remains unclear. METHODS: The authors examined short-term alcohol intake in relation to recurrence and mortality in 3659 women who were diagnosed with stage I-IV BC from 2003 to 2013 in the Pathways Study. Alcohol drinking in the past 6 months was assessed at cohort entry (mean, 2 months postdiagnosis) and 6 months later using a food-frequency questionnaire. Study end points were recurrence and death from BC, cardiovascular disease, and all causes. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox proportional hazards models. RESULTS: Over an average follow-up of 11.2 years, 524 recurrences and 834 deaths (369 BC-specific and 314 cardiovascular disease-specific) occurred. Compared with nondrinkers (36.9%), drinkers were more likely younger, more educated, and current or past smokers. Overall, alcohol consumption was not associated with recurrence or mortality. However, women with higher body mass index (BMI ≥ 30 kg/m2 ) had lower risk of overall mortality with increasing alcohol consumption for occasional drinking (HR, 0.71; 95% CI, 0.54-0.94) and regular drinking (HR, 0.77; 95% CI, 0.56-1.08) around the time of diagnosis, along with 6 months later, in a dose-response manner (p < .05). Women with lower BMI (<30 kg/m2 ) were not at higher risk of mortality but were at possibly higher, yet nonsignificant, risk of recurrence for occasional drinking (HR, 1.29; 95% CI, 0.97-1.71) and regular drinking (HR, 1.19; 95% CI, 0.88-1.62). CONCLUSIONS: Alcohol drinking around the time of and up to 6 months after BC diagnosis was associated with lower risk of all-cause mortality in obese women. A possible higher risk of recurrence was observed in nonobese women.

Adiposity and cancer survival: a systematic review and meta-analysis.

PURPOSE: The increasing availability of clinical imaging tests (especially CT and MRI) that directly quantify adipose tissue has led to a rapid increase in studies examining the relationship of visceral, subcutaneous, and overall adiposity to cancer survival. To summarize this emerging body of literature, we conducted a systematic review and meta-analysis of imaging-measured as well as anthropometric proxies for adipose tissue distribution and cancer survival across a wide range of cancer types. METHODS: Using keywords related to adiposity, cancer, and survival, we conducted a systematic search of the literature in PubMed and MEDLINE, Embase, and Web of Science Core Collection databases from database inception to 30 June 2021. We used a random-effect method to calculate pooled hazard ratios (HR) and corresponding 95% confidence intervals (CI) within each cancer type and tested for heterogeneity using Cochran's Q test and the I2 test. RESULTS: We included 203 records for this review, of which 128 records were utilized for quantitative analysis among 10 cancer types: breast, colorectal, gastroesophageal, head and neck, hepatocellular carcinoma, lung, ovarian, pancreatic, prostate, and renal cancer. We found that imaging-measured visceral, subcutaneous, and total adiposity were not significantly associated with increased risk of overall mortality, death from primary cancer, or cancer progression among patients diagnosed with these 10 cancer types; however, we found significant or high heterogeneity for many cancer types. For example, heterogeneity was similarly high when the pooled HRs (95% CI) for overall mortality associated with visceral adiposity were essentially null as in 1.03 (0.55, 1.92; I2 = 58%) for breast, 0.99 (0.81, 1.21; I2 = 71%) for colorectal, versus when they demonstrated a potential increased risk 1.17 (0.85, 1.60; I2 = 78%) for hepatocellular carcinoma and 1.62 (0.90, 2.95; I2 = 84%) for renal cancer. CONCLUSION: Greater adiposity at diagnosis (directly measured by imaging) is not associated with worse survival among cancer survivors. However, heterogeneity and other potential limitations were noted across studies, suggesting differences in study design and adiposity measurement approaches, making interpretation of meta-analyses challenging. Future work to standardize imaging measurements and data analyses will strengthen research on the role of adiposity in cancer survival.

Metabolic abnormalities and survival among patients with non-metastatic breast cancer.

BACKGROUND: Research on the impact of metabolic abnormalities on breast cancer prognosis is limited by small samples and assessment of laboratory values at a single time point, often prior to cancer diagnosis and treatment. In this population-based cohort, time-updated laboratory values were adjusted for cancer treatment to assess the association between metabolic risk factors (glucose, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides) and breast cancer survival. METHODS: 13,434 women diagnosed with stage I-III breast cancer from 2005-15 at Kaiser Permanente were included. All outpatient fasting glucose, HDL-C, LDL-C, and triglyceride values from diagnosis through 2019 or death were extracted from electronic medical records. Risk of breast cancer-specific mortality was evaluated with Cox proportional hazards models adjusted for metabolic labs, demographics, body mass index, diabetes, dyslipidemia and anti-hypertensive medications, tumor characteristics (stage, ER and HER2 receptor status) and cancer treatment (use of chemotherapy, tamoxifen, and aromatase inhibitors). RESULTS: Mean (SD) age at diagnosis was 62.3 (11.8) years. Over a median follow-up of 8.6 years, 2,876 patients died; 1,080 of breast cancer. Patients with low HDL-C (≤ 45 vs. > 45 mg/dL) had higher breast cancer-specific mortality (HR, 1.77; 95% CI, 1.53-2.05), as did those with elevated fasting glucose (> 99 vs. 60-99 mg/dL) (HR, 1.19; 95% CI, 1.03-1.37). Elevated levels of triglycerides and LDL-C were not associated with breast cancer-specific mortality. CONCLUSIONS: High fasting glucose and low HDL-C evaluated over time after cancer diagnosis were associated with higher breast cancer mortality independent of cancer treatments and changes in other metabolic risk factors. Future studies should address whether pharmacologic or lifestyle treatment of glucose and lipids after breast cancer diagnosis can optimize survival outcomes.

Genetic architectures of proximal and distal colorectal cancer are partly distinct.

OBJECTIVE: An understanding of the etiologic heterogeneity of colorectal cancer (CRC) is critical for improving precision prevention, including individualized screening recommendations and the discovery of novel drug targets and repurposable drug candidates for chemoprevention. Known differences in molecular characteristics and environmental risk factors among tumors arising in different locations of the colorectum suggest partly distinct mechanisms of carcinogenesis. The extent to which the contribution of inherited genetic risk factors for CRC differs by anatomical subsite of the primary tumor has not been examined. DESIGN: To identify new anatomical subsite-specific risk loci, we performed genome-wide association study (GWAS) meta-analyses including data of 48 214 CRC cases and 64 159 controls of European ancestry. We characterised effect heterogeneity at CRC risk loci using multinomial modelling. RESULTS: We identified 13 loci that reached genome-wide significance (p<5×10-8) and that were not reported by previous GWASs for overall CRC risk. Multiple lines of evidence support candidate genes at several of these loci. We detected substantial heterogeneity between anatomical subsites. Just over half (61) of 109 known and new risk variants showed no evidence for heterogeneity. In contrast, 22 variants showed association with distal CRC (including rectal cancer), but no evidence for association or an attenuated association with proximal CRC. For two loci, there was strong evidence for effects confined to proximal colon cancer. CONCLUSION: Genetic architectures of proximal and distal CRC are partly distinct. Studies of risk factors and mechanisms of carcinogenesis, and precision prevention strategies should take into consideration the anatomical subsite of the tumour.

Alignment of Dietary Patterns With the Dietary Guidelines for Americans 2015-2020 and Risk of All-Cause and Cause-Specific Mortality in the Women's Health Initiative Observational Study.

Poor diet quality is a leading risk factor for death in the United States. We examined the association between Healthy Eating Index-2015 (HEI-2015) scores and death from all causes, cardiovascular disease (CVD), cancer, Alzheimer disease, and dementia not otherwise specified (NOS) among postmenopausal women in the Women's Health Initiative Observational Study (1993-2017). This analysis included 59,388 participants who completed a food frequency questionnaire and were free of cancer, CVD, and diabetes at enrollment. Stratified Cox proportional hazards models were fit using person-years from enrollment as the underlying time metric. We estimated multivariable adjusted hazard ratios and 95% confidence intervals for risk of death associated with HEI-2015 quintiles, with higher scores reflecting more optimal diet quality. Over a median of 18.2 years, 9,679 total deaths 3,303 cancer deaths, 2,362 CVD deaths, and 488 deaths from Alzheimer disease and dementia NOS occurred. Compared with those with lower scores, women with higher HEI-2015 scores had an 18% lower risk of all-cause death and 21% lower risk of cancer death. HEI-2015 scores were not associated with death due to CVD, Alzheimer disease, and dementia NOS. Consuming a diet aligned with 2015-2020 US dietary guidelines may have beneficial impacts for preventing overall causes of death and death from cancer.

Individual- and neighborhood-level socioeconomic status and risk of aggressive breast cancer subtypes in a pooled cohort of women from Kaiser Permanente Northern California.

BACKGROUND: Low socioeconomic status (SES) has been associated with a higher risk of aggressive breast cancer (BC) subtypes, but few studies have examined the independent effects of both neighborhood-level socioeconomic status (nSES) and individual-level SES measures. METHODS: This study included 5547 women from the Pathways and Life After Cancer Epidemiology cohorts who were diagnosed with invasive BC. Generalized estimating equation models were used to examine associations of nSES (a composite score based on income, poverty, education, occupation, employment, rent, and house value) and individual-level SES (income and education) with BC subtypes: luminal B (LumB), Her2-enriched (Her2-e), and triple-negative breast cancer (TNBC) relative to luminal A (LumA). Models controlled for age, race, nativity, stage, days from diagnosis to survey, and study cohort and simultaneously for nSES and individual-level SES. RESULTS: In fully adjusted models, low nSES was significantly associated with the LumB (odds ratio for quartile 1 vs quartile 4 [ORQ1vQ4 ], 1.31; 95% confidence interval [CI], 1.11-1.54; P for trend = .005) and TNBC subtypes (ORQ1vQ4 , 1.32; 95% CI, 1.02-1.71; P for trend = .037) relative to LumA. Conversely, individual education was significantly associated with only the Her2-e subtype (odds ratio for high school degree or less vs postgraduate, 1.68; 95% CI, 1.03-2.75; P for trend = .030) relative to LumA. Individual income was not significantly associated with any BC subtype. CONCLUSIONS: nSES and individual-level SES are independently associated with different BC subtypes; specifically, low nSES and individual-level education are independent predictors of more aggressive BC subtypes relative to LumA.

Cardiometabolic risk factors and survival after cancer in the Women's Health Initiative.

BACKGROUND: Cardiometabolic abnormalities are a leading cause of death among women, including women with cancer. METHODS: This study examined the association between prediagnosis cardiovascular health and total and cause-specific mortality among 12,076 postmenopausal women who developed local- or regional-stage invasive cancer in the Women's Health Initiative (WHI). Cardiovascular risk factors included waist circumference, hypertension, high cholesterol, and type 2 diabetes. Obesity-related cancers included breast cancer, colorectal cancer, endometrial cancer, kidney cancer, pancreatic cancer, ovarian cancer, stomach cancer, liver cancer, and non-Hodgkin lymphoma. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) adjusted for important predictors of survival. RESULTS: After a median follow-up of 10.0 years from the date of the cancer diagnosis, there were 3607 total deaths, with 1546 (43%) due to cancer. Most participants (62.9%) had 1 or 2 cardiometabolic risk factors, and 8.1% had 3 or 4. In adjusted models, women with 3 to 4 risk factors (vs none) had a higher risk of all-cause mortality (HR, 1.99; 95% CI, 1.73-2.30), death due to cardiovascular disease (CVD) (HR, 4.01; 95% CI, 2.88-5.57), cancer-specific mortality (HR, 1.37; 95% CI, 1.1-1.72), and other-cause mortality (HR, 2.14; 95% CI, 1.70-2.69). A higher waist circumference was associated with greater all-cause mortality (HR, 1.17; 95% CI, 1.06-1.30) and cancer-specific mortality (HR, 1.22; 95% CI, 1.04-1.42). CONCLUSIONS: Among postmenopausal women diagnosed with cancer in the WHI, cardiometabolic risk factors before the cancer diagnosis were associated with greater all-cause, CVD, cancer-specific, and other-cause mortality. These results raise hypotheses regarding potential clinical intervention strategies targeting cardiometabolic abnormalities that require future prospective studies for confirmation. LAY SUMMARY: This study uses information from the Women's Health Initiative (WHI) to find out whether cardiac risk factors are related to a greater risk of dying among older women with cancer. The WHI is the largest study of medical problems faced by older women in this country. The results show that women who have 3 or 4 risk factors are more likely to die of any cause, heart disease, or cancer in comparison with women with no risk factors. It is concluded that interventions to help to lower the burden of cardiac risk factors can have an important impact on survivorship among women with cancer.

Guideline-concordant endometrial cancer treatment and survival in the Women's Health Initiative Life and Longevity After Cancer study.

In the Women's Health Initiative (WHI) Life and Longevity After Cancer (LILAC) cohort, we examined predictors of guideline-concordant treatment among endometrial cancer (EC) survivors and associations between receipt of guideline-concordant treatment and survival. Receipt of guideline-concordant EC treatment was defined according to year-specific National Comprehensive Cancer Network (NCCN) guidelines. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for predictors of guideline-concordant treatment receipt. We estimated multivariable-adjusted hazard ratios (HRs) and 95% CIs for relationships between guideline-concordant treatment and overall survival using Cox proportional hazards regression. We included 629 women with EC, of whom 83.6% (n = 526) received guideline-concordant treatment. Receipt of guideline-concordant treatment was less common among women with nonendometrioid histology (OR = 0.24, 95% CI = 0.13-0.45) but was more common among women living in the Midwest (OR = 2.09, 95% CI = 1.06-4.12) or West (OR = 3.02, 95% CI = 1.49-6.13) compared to the Northeast. In Cox regression models adjusted for age, histology and stage, receipt of guideline-concordant EC treatment was borderline associated with improved overall survival (HR = 0.80, 95% CI = 0.60-1.01) in the overall population. Guideline-concordant treatment was also linked with better overall survival among women with low-grade uterine-confined endometrioid EC or widely metastatic endometrioid EC. Guideline-concordant treatment varies by some patient characteristics and those women in receipt of guideline-concordant care had borderline improved survival. Studies evaluating regional differences in treatment along with randomized clinical trials to determine appropriate treatment regimens for women with aggressive tumor characteristics are warranted.

Meta-analysis of 16 studies of the association of alcohol with colorectal cancer.

Alcohol consumption is an established risk factor for colorectal cancer (CRC). However, while studies have consistently reported elevated risk of CRC among heavy drinkers, associations at moderate levels of alcohol consumption are less clear. We conducted a combined analysis of 16 studies of CRC to examine the shape of the alcohol-CRC association, investigate potential effect modifiers of the association, and examine differential effects of alcohol consumption by cancer anatomic site and stage. We collected information on alcohol consumption for 14,276 CRC cases and 15,802 controls from 5 case-control and 11 nested case-control studies of CRC. We compared adjusted logistic regression models with linear and restricted cubic splines to select a model that best fit the association between alcohol consumption and CRC. Study-specific results were pooled using fixed-effects meta-analysis. Compared to non-/occasional drinking (≤1 g/day), light/moderate drinking (up to 2 drinks/day) was associated with a decreased risk of CRC (odds ratio [OR]: 0.92, 95% confidence interval [CI]: 0.88-0.98, p = 0.005), heavy drinking (2-3 drinks/day) was not significantly associated with CRC risk (OR: 1.11, 95% CI: 0.99-1.24, p = 0.08) and very heavy drinking (more than 3 drinks/day) was associated with a significant increased risk (OR: 1.25, 95% CI: 1.11-1.40, p < 0.001). We observed no evidence of interactions with lifestyle risk factors or of differences by cancer site or stage. These results provide further evidence that there is a J-shaped association between alcohol consumption and CRC risk. This overall pattern was not significantly modified by other CRC risk factors and there was no effect heterogeneity by tumor site or stage.

DNA repair and cancer in colon and rectum: Novel players in genetic susceptibility.

Interindividual differences in DNA repair systems may play a role in modulating the individual risk of developing colorectal cancer. To better ascertain the role of DNA repair gene polymorphisms on colon and rectal cancer risk individually, we evaluated 15,419 single nucleotide polymorphisms (SNPs) within 185 DNA repair genes using GWAS data from the Colon Cancer Family Registry (CCFR) and the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), which included 8,178 colon cancer, 2,936 rectum cancer cases and 14,659 controls. Rs1800734 (in MLH1 gene) was associated with colon cancer risk (p-value = 3.5 × 10-6 ) and rs2189517 (in RAD51B) with rectal cancer risk (p-value = 5.7 × 10-6 ). The results had statistical significance close to the Bonferroni corrected p-value of 5.8 × 10-6 . Ninety-four SNPs were significantly associated with colorectal cancer risk after Binomial Sequential Goodness of Fit (BSGoF) procedure and confirmed the relevance of DNA mismatch repair (MMR) and homologous recombination pathways for colon and rectum cancer, respectively. Defects in MMR genes are known to be crucial for familial form of colorectal cancer but our findings suggest that specific genetic variations in MLH1 are important also in the individual predisposition to sporadic colon cancer. Other SNPs associated with the risk of colon cancer (e.g., rs16906252 in MGMT) were found to affect mRNA expression levels in colon transverse and therefore working as possible cis-eQTL suggesting possible mechanisms of carcinogenesis.

Prediagnosis social support, social integration, living status, and colorectal cancer mortality in postmenopausal women from the women's health initiative.

BACKGROUND: We evaluated associations between perceived social support, social integration, living alone, and colorectal cancer (CRC) outcomes in postmenopausal women. METHODS: The study included 1431 women from the Women's Health Initiative who were diagnosed from 1993 through 2017 with stage I through IV CRC and who responded to the Medical Outcomes Study Social Support survey before their CRC diagnosis. We used proportional hazards regression to evaluate associations of social support (tertiles) and types of support, assessed up to 6 years before diagnosis, with overall and CRC-specific mortality. We also assessed associations of social integration and living alone with outcomes also in a subset of 1141 women who had information available on social ties (marital/partner status, community and religious participation) and living situation. RESULTS: In multivariable analyses, women with low (hazard ratio [HR], 1.52; 95% CI, 1.23-1.88) and moderate (HR, 1.21; 95% CI, 0.98-1.50) perceived social support had significantly higher overall mortality than those with high support (P [continuous] < .001). Similarly, women with low (HR, 1.42; 95% CI, 1.07-1.88) and moderate (HR, 1.28; 95% CI, 0.96-1.70) perceived social support had higher CRC mortality than those with high social support (P [continuous] = .007). Emotional, informational, and tangible support and positive interaction were all significantly associated with outcomes, whereas affection was not. In main-effects analyses, the level of social integration was related to overall mortality (P for trend = .02), but not CRC mortality (P for trend = .25), and living alone was not associated with mortality outcomes. However, both the level of social integration and living alone were related to outcomes in patients with rectal cancer. CONCLUSIONS: Women with low perceived social support before diagnosis have higher overall and CRC-specific mortality.

Genetic variant predictors of gene expression provide new insight into risk of colorectal cancer.

Genome-wide association studies have reported 56 independently associated colorectal cancer (CRC) risk variants, most of which are non-coding and believed to exert their effects by modulating gene expression. The computational method PrediXcan uses cis-regulatory variant predictors to impute expression and perform gene-level association tests in GWAS without directly measured transcriptomes. In this study, we used reference datasets from colon (n = 169) and whole blood (n = 922) transcriptomes to test CRC association with genetically determined expression levels in a genome-wide analysis of 12,186 cases and 14,718 controls. Three novel associations were discovered from colon transverse models at FDR ≤ 0.2 and further evaluated in an independent replication including 32,825 cases and 39,933 controls. After adjusting for multiple comparisons, we found statistically significant associations using colon transcriptome models with TRIM4 (discovery P = 2.2 × 10- 4, replication P = 0.01), and PYGL (discovery P = 2.3 × 10- 4, replication P = 6.7 × 10- 4). Interestingly, both genes encode proteins that influence redox homeostasis and are related to cellular metabolic reprogramming in tumors, implicating a novel CRC pathway linked to cell growth and proliferation. Defining CRC risk regions as one megabase up- and downstream of one of the 56 independent risk variants, we defined 44 non-overlapping CRC-risk regions. Among these risk regions, we identified genes associated with CRC (P < 0.05) in 34/44 CRC-risk regions. Importantly, CRC association was found for two genes in the previously reported 2q25 locus, CXCR1 and CXCR2, which are potential cancer therapeutic targets. These findings provide strong candidate genes to prioritize for subsequent laboratory follow-up of GWAS loci. This study is the first to implement PrediXcan in a large colorectal cancer study and findings highlight the utility of integrating transcriptome data in GWAS for discovery of, and biological insight into, risk loci.

Correction to: Genetic variant predictors of gene expression provide new insight into risk of colorectal cancer.

Every author has erroneously been assigned to the affiliation "62". The affiliation 62 belongs to the author Graham Casey.

Non-alcoholic fatty liver disease and colorectal cancer survival.

PURPOSE: Liver diseases including non-alcoholic fatty liver disease (NAFLD) and ensuing alterations to the micro-environment may affect development of liver metastasis. Mirroring the rise in obesity rates, prevalence of NAFLD is increasing globally. Our objective was to examine the association between NAFLD and mortality in colorectal cancer patients. METHODS: Colorectal Cancer-Sarcopenia and Near-term Survival (C-SCANS) is a retrospective cohort study which included 3,262 stage I-III patients, aged 18-80 years, and diagnosed between 2006 and 2011 at Kaiser Permanente Northern California. Cox proportional hazards regression was used to calculate multivariable adjusted hazard ratios (HR) and 95% confidence intervals (CI). RESULTS: After up to 10 years of follow-up, 879 deaths, including 451 from CRC were identified. Cases diagnosed with NAFLD before and within 1 month after CRC diagnosis (pre-existing NAFLD; n = 83) had a HR of 1.64 (95% CI 1.06-2.54) for overall and a HR of 1.85 (95% CI 1.03-3.30) for CRC-specific mortality compared to those without NAFLD. Findings did not differ significantly by sex, stage, tumor location, and smoking status, and were also similar when restricted to obese patients only. CONCLUSIONS: Independent of body mass index and prognostic indicators, CRC patients with pre-existing NAFLD had a worse prognosis than those without NAFLD.

The Obesity Paradox in Cancer: How Important Is Muscle?

Although higher body mass index (BMI) increases the incidence of many cancers, BMI can also exhibit a null or U-shaped relationship with survival among patients with existing disease; this association of higher BMI with improved survival is termed the obesity paradox. This review discusses possible explanations for the obesity paradox, the prevalence and consequences of low muscle mass in cancer patients, and future research directions. It is unlikely that methodological biases, such as reverse causality or confounding, fully explain the obesity paradox. Rather, up to a point, higher BMI may truly be associated with longer survival in cancer patients. This is due, in part, to the limitations of BMI, which scales weight to height without delineating adipose tissue distribution or distinguishing between adipose and muscle tissue. Thus, cancer patients with higher BMIs often have higher levels of protective muscle. We assert that more precise measures of body composition are required to clarify the relationship of body size to cancer outcomes, inform clinical decision-making, and help tailor lifestyle interventions.