Cancer incidence in relation to body fatness among 0.5 million men and women: Findings from the China Kadoorie Biobank

Adiposity and risks of gastrointestinal cancers: A 10-year prospective study of 0.5 million Chinese adults

Associations of adiposity with risks of oesophageal squamous cell carcinoma (ESCC) and non-cardia stomach cancer, both prevalent in China, are still inconclusive. While adiposity is an established risk factor for colorectal cancer, the relevance of fat-free mass and early-adulthood adiposity remains to be explored. The prospective China Kadoorie Biobank study included 0.5 million adults (aged 30-79 years) from 10 areas in China. Participants' body size and composition were measured at baseline and at resurveys (amongst a subset). After >10 years of follow-up, 2350, 3345 and 3059 incident cases of oesophageal (EC), stomach (SC) and colorectal (CRC) cancers were recorded, respectively. Cox regression was used to estimate hazard ratios (HRs) for these cancers in relation to different adiposity traits. General and central adiposity were inversely associated with EC (primarily ESCC) risk, with HRs of 0.81 (95% CI 0.77-0.85), 0.76 (0.72-0.81) and 0.87 (0.83-0.92) per SD increase in usual levels of BMI, body fat percentage (BF%) and waist circumference (WC), respectively. Adiposity was also inversely associated with SC risk [HR = 0.79 (0.75-0.83) and 0.88 (0.84-0.92) per SD increase in usual BF% and WC], with heterogeneity by cardia and non-cardia subsites, and positively associated with CRC [HR = 1.09 (1.03-1.15) and 1.17 (1.12-1.22) per SD higher usual BF% and WC]. Fat-free mass was inversely associated with EC [HR = 0.93 (0.89-0.98) per SD increase] but positively associated with CRC [1.09 (1.04-1.14)], while BMI at age 25 was positively associated with all three cancers. After mutual adjustment, general adiposity remained inversely associated with EC and SC, while central adiposity remained positively associated with CRC.

Body mass index and breast cancer risk in premenopausal and postmenopausal East Asian women: a pooled analysis of 13 cohort studies

BACKGROUND

It has been suggested that the association between body mass index and breast cancer risk differs between Asian women and Western women. We aimed to assess the associations between body mass index and breast cancer incidence in East Asian women.

METHODS

Pooled analyses were performed using individual participant data of 319,189 women from 13 cohort studies in Japan, Korea, and China. Participants' height and weight were obtained by measurement or self-reports at cohort baseline. Breast cancer was defined as code C50.0-C50.9 according to the International Classification. Using a Cox proportional hazards model, hazard ratios of breast cancer were estimated for each body mass index category, with the reference group set as the group with a body mass index of 21 to < 23 kg/m2. The hazard ratio for a 5 kg/m2 increase in body mass index was also calculated.

RESULTS

During a mean 16.6 years of follow-up, 4819 women developed breast cancer. Similar to Westerners, a steady increase in breast cancer risk with increasing body mass index was observed in postmenopausal women, but the slope of the risk increase appeared to slow at a body mass index of 26-28 kg/m2. In premenopausal women, the inverse association seen in Westerners was not observed. The risk of developing breast cancer after 50 years of age increased slightly with increasing body mass index, which was more pronounced in the older birth cohort. There was no significant association between body mass index and the risk of developing breast cancer before 50 years of age, but the risk estimates changed from positive to negative as the birth cohort got younger.

CONCLUSIONS

In East Asia, the role of body mass index in breast cancer in premenopausal women may be changing along with the increase in obesity and breast cancer. The increased risk of postmenopausal breast cancer with a higher body mass index was as robust as that of Western women.

Overweight and obesity significantly increase colorectal cancer risk: a meta-analysis of 66 studies revealing a 25-57% elevation in risk

The incidence of colorectal cancer (CRC) has been steadily rising, and obesity has been identified as a significant risk factor. Numerous studies suggest a strong correlation between excess body weight and increased risk of CRC, but comprehensive quantification through pooled analysis remains limited. This study aims to systematically review and meta-analyze the existing literature to evaluate the association between obesity and CRC risk, considering variations across sex and study designs. A systematic literature search was conducted in PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science to identify randomized controlled trials and human clinical trials from 1992 to 2024. Statistical analysis was performed using the https://metaanalysisonline.com web application using a random effects model to estimate the pooled hazard rates (HR). Forest plots, funnel plots, and Z-score plots were utilized to visualize results. We identified 52 clinical trials and 14 case-control studies, encompassing a total of 83,251,050 and 236,877 subjects, respectively. The pooled analysis indicated that obesity significantly increased the prevalence of CRC (HR = 1.36, 95% CI = 1.24-1.48, p < 0.01). This effect was consistent across sexes, with HRs of 1.57 (95% CI = 1.38-1.78, p = 0.01) for males and 1.25 (95% CI = 1.14-1.38, p < 0.01) for females. Case-control studies specifically showed an effect, but with marginal significance only (HR = 1.27, 95% CI = 0.98-1.65, p = 0.07). The Z-score plot indicated the need for additional analysis in the case-control group. A significant heterogeneity was observed across studies in all four settings. This meta-analysis provides robust evidence that obesity is a significant risk factor for colorectal cancer, with an overall hazard rate indicating a 36% increased risk. The effect is pronounced across both sexes, with males showing a slightly higher risk compared to females. Although case-control studies showed a weaker association, the overall trend supports the link between obesity and CRC. These results underscore the importance of public health interventions aimed at reducing obesity to potentially lower the risk of colorectal cancer.

Metabolic dysregulation in obese women and the carcinogenesis of gynecological tumors: A review

Obesity is a significant health issue associated with increased cancer risks, including gynecological malignancies. The worldwide rise in obesity rates is significantly impacting both cancer development and treatment outcomes. Adipose tissue plays a crucial role in metabolism, secreting various substances that can influence cancer formation. In obese individuals, dysfunctional adipose tissue can contribute to cancer development through inflammation, insulin resistance, hormonal changes, and abnormal cholesterol metabolism. Studies have shown a strong correlation between obesity and gynecological cancers, particularly endometrial and breast cancers. Obesity not only increases the risk of developing these cancers but is also associated with poorer outcomes. Additionally, obesity affects the perioperative management of gynecological cancers, requiring specialized care due to increased complications and resistance to therapy. Treatment strategies for managing metabolic dysregulation in patients with gynecological cancers include weight management, statin therapy, and insulin-sensitizing medications. Emerging studies suggest that interventions like intermittent fasting and caloric restriction may enhance the effectiveness of cancer treatments. Furthermore, targeting cholesterol metabolism, such as with statins or proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, shows potential in cancer therapy. In conclusion, addressing metabolic issues, particularly obesity, is crucial in preventing and treating gynecological malignancies. Personalized approaches focusing on weight management and metabolic reprogramming may improve outcomes in these patients.

Adiposity and cancer: meta-analysis, mechanisms, and future perspectives

Obesity is a recognised risk factor for many cancers and with rising global prevalence, has become a leading cause of cancer. Here we summarise the current evidence from both population-based epidemiologic investigations and experimental studies on the role of obesity in cancer development. This review presents a new meta-analysis using data from 40 million individuals and reports positive associations with 19 cancer types. Utilising major new data from East Asia, the meta-analysis also shows that the strength of obesity and cancer associations varies regionally, with stronger relative risks for several cancers in East Asia. This review also presents current evidence on the mechanisms linking obesity and cancer and identifies promising future research directions. These include the use of new imaging data to circumvent the methodological issues involved with body mass index and the use of omics technologies to resolve biologic mechanisms with greater precision and clarity.

Naringin ameliorates obesity via stimulating adipose thermogenesis and browning, and modulating gut microbiota in diet-induced obese mice

Naringin, a natural flavanone primarily found in citrus fruits, has garnered increased attention due to its recognized antioxidative, anti-inflammatory, and cardioprotective attributes. However, the functions of naringin in regulating energy expenditure are poorly understood. In the present study, we observed that twelve weeks of naringin supplementation substantially reshaped the metabolic profile of high-fat diet (HFD)-fed mice, by inhibiting body weight gain, reducing liver weight, and altering body compositions. Notably, naringin exhibited a remarkable capacity to augment whole-body energy expenditure of the tested mice by enhancing the thermogenic activity of brown adipose tissue (BAT) and stimulating browning of inguinal white adipose tissue (iWAT). Furthermore, our results showed naringin supplementation modified gut microbiota composition, specifically increasing the abundance of Bifidobacterium and Lachnospiraceae_bacterium_28-4, while reducing the abundance of Lachnospiraceae_bacterium_DW59 and Dubosiella_newyorkensis. Subsequently, we also found naringin supplementation altered fecal metabolite profile, by significantly promoting the production of taurine, tyrosol, and thymol, which act as potent activators of thermoregulation. Interestingly, the metabolic effects of naringin were abolished upon gut microbiota depletion through antibiotic intervention, concurrently leading the disappearance of naringin-induced thermogenesis and protective actions on diet-induced obesity. This discovery revealed a novel food-driven cross-sectional communication between gut bacteria and adipose tissues. Collectively, our data indicate that naringin supplementation stimulates BAT thermogenesis, alters fat distribution, promotes the browning process, and consequently inhibits body weight gain; importantly these metabolic effects require the participation of gut bacteria.

Adiposity and risk of oesophageal cancer subtypes in the Million Women Study

BACKGROUND

The strong association of body mass index (BMI) with increased oesophageal adenocarcinoma risk is established, but its relationship with oesophageal squamous cell carcinoma is less clear. There is little evidence regarding the association of abdominal adiposity with either subtype.

METHODS

In a large prospective cohort of women in the UK, mean age 56.2 [standard deviation (SD) = 4.9] years, we investigated the risk of oesophageal adenocarcinoma and squamous cell carcinoma in relation to self-reported BMI, waist circumference (WC) and waist-hip ratio (WHR), using Cox regression to estimate adjusted relative risks (RR) and 95% confidence intervals (CIs), taking account of potential reverse causation bias.

RESULTS

During mean follow-up of 17.7 (SD = 4.9) years, 1386 adenocarcinomas and 1799 squamous cell carcinomas of the oesophagus were registered among 1 255 529 women. Compared with women of BMI 22.5 to <25 kg/m2, those with BMI ≥35 kg/m2 had a 2.5-fold risk of adenocarcinoma (adjusted RR = 2.46, 95% CI = 1.99-3.05) and an almost 70% reduction in risk of squamous cell carcinoma (RR = 0.32, 95% CI = 0.22-0.46). These associations were broadly similar in each 5-year follow-up period, and were evident in both never and ever smokers, although somewhat stronger for squamous cell carcinoma among current and past smokers than in never smokers (Pheterogeneity = 0.007). After controlling for BMI, WC and WHR were associated with risk of squamous cell carcinoma but not adenocarcinoma.

CONCLUSIONS

In this population of middle-aged women, there was robust evidence that greater BMI is associated with an increased risk of oesophageal adenocarcinoma and a reduced risk of squamous cell carcinoma.

Gastric Cancer Risk in Association with Underweight, Overweight, and Obesity: A Systematic Review and Meta-Analysis

This study aimed to investigate the risk of gastric cancer (GC) in abnormal body mass index (BMI) groups. A systematic search was carried out on Embase, PubMed/Medline, and Scopus from January 2000 to January 2023. The pooled risk ratio (RR) with a 95% confidence interval (CI) was assessed using a random-effect model. Thirteen studies with total of 14,020,031 participants were included in this systematic review. The pooled RR of GC was 1.124 (95% CI, 0.968-1.304, I²: 89.08%) in underweight class, 1.155 (95% CI, 1.051-1.270, I²: 95.18%) in overweight class, and in 1.218 (95% CI, 1.070-1.386, I²: 97.65%) obesity class. There is no difference between cardia and non-cardia gastric cancer, while non-Asian race and female gender have higher risk of cancer, as Meta-regression of obesity and overweight classes showed. These findings suggest that there is a positive association between excess body weight and the risk of GC, with a higher impact in women than men and in non-Asian than Asian populations. Since abnormal weight is tied to various diseases, including GC, healthcare experts, and policymakers should continue interventions aiming to achieve a normal BMI range.

Anthropometric indicators of adiposity and risk of primary liver cancer: A systematic review and dose-response meta-analysis

BACKGROUND AND AIMS

Adiposity is associated with an increased risk of primary liver cancer (PLC). As the most commonly used indicator of adiposity, the body mass index (BMI) has been questioned for its limitations in reflecting visceral fat. This study aimed to investigate the role of different anthropometric indicators in identifying the risk of PLC by accounting for potential non-linear associations.

METHODS

Systematic searches were conducted in the PubMed, Embase, Cochrane Library, Sinomed, Web of Science, and CNKI databases. Hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were used to assess the pooled risk. The dose-response relationship was assessed using a restricted cubic spline model.

RESULTS

Sixty-nine studies involving more than 30 million participants were included in the final analysis. Regardless of the indicator used, adiposity was strongly associated with an increased risk of PLC. When comparing the HRs per 1-standard deviation increment across indicators of adiposity, the association was strongest for waist-to-height ratio (WHtR) (HR = 1.39), followed by waist-to-hip ratio (WHR) (HR = 1.22), BMI (HR = 1.13), waist circumference (WC) (HR = 1.12), and hip circumference (HC) (HR = 1.12). A strong non-linear association was observed between each anthropometric parameter and the risk of PLC, regardless of whether the original or decentralised value was used. The positive association between WC and PLC risk remained substantial after adjusting for BMI. The incidence of PLC was higher with central adiposity (52.89 per 100,000 person-years, 95% CI = 50.33-55.44) than general adiposity (39.01 per 100,000 person-years, 95% CI = 37.26-40.75).

CONCLUSION

Central adiposity seems to contribute more to the development of PLC than general adiposity. A larger WC, independent of BMI, was strongly associated with the risk of PLC and might be a more promising predictive indicator than BMI.

Self-Reported Primary Cooking Fuels Use and Risk of Chronic Digestive Diseases: A Prospective Cohort Study of 0.5 Million Chinese Adults

BACKGROUND

Household air pollution (HAP) from inefficient combustion of solid fuels is a major health concern worldwide. However, prospective evidence on the health impacts of solid cooking fuels and risks of chronic digestive diseases remains scarce.

OBJECTIVES

We explored the effects of self-reported primary cooking fuels on the incidence of chronic digestive diseases.

METHODS

The China Kadoorie Biobank recruited 512,726 participants 30-79 years of age from 10 regions across China. Information on primary cooking fuels at the current and previous two residences was collected via self-reporting at baseline. Incidence of chronic digestive diseases was identified through electronic linkage and active follow-up. Cox proportional hazards regression models were used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations of self-reported long-term cooking fuel patterns and weighted duration of self-reported solid cooking fuel use with chronic digestive diseases incidence. Linear trend was tested by assigning the medians of weighted duration in each group and then taking those as continuous variables in the models. Subgroup analyses were undertaken across the baseline characteristics of participants.

RESULTS

During 9.1 ± 1.6 y of follow-up, 16,810 new cases of chronic digestive diseases were documented, among which 6,460 were diagnosed as cancers. Compared with long-term cleaner fuel use, self-reported long-term use of solid cooking fuels (i.e., coal, wood) was associated with elevated risks of chronic digestive diseases (HR = 1.08 ; 95% CI: 1.02, 1.13), including nonalcoholic fatty liver disease (NAFLD) (HR = 1.43 ; 95% CI: 1.10, 1.87), hepatic fibrosis/cirrhosis (HR = 1.35 ; 95% CI: 1.05, 1.73), cholecystitis (HR = 1.19 ; 95% CI: 1.07, 1.32), and peptic ulcers (HR = 1.15 ; 95% CI: 1.00, 1.33). The longer the weighted duration of self-reported solid cooking fuel use, the higher the risks of chronic digestive diseases, hepatic fibrosis/cirrhosis, peptic ulcers, and esophageal cancer (p Trend < 0.05 ). The aforementioned associations were modified by sex and body mass index (BMI). Positive associations of always solid cooking fuel use with chronic digestive disease, hepatic fibrosis/cirrhosis, NAFLD, and cholecystitis were observed among women but not men. The longer the weighted duration of self-reported solid cooking fuel use, the higher the risk of NAFLD among those with a BMI ≥ 28   kg / m 2 .

DISCUSSION

Long-term self-reported solid cooking fuels use was associated with higher risks of chronic digestive diseases. The positive association of HAP from solid cooking fuels with chronic digestive diseases indicates for an imminent promotion of cleaner fuels as public health interventions. https://doi.org/10.1289/EHP10486.

Female reproductive and hormonal factors and lung cancer mortality among never-smokers: A prospective cohort study of 287 408 Chinese women

There is growing, but inconsistent evidence suggesting oestrogen may play a key role in lung cancer development, especially among never-smoking women for whom lung cancer risk factors remain largely elusive. Using the China Kadoorie Biobank, a large-scale prospective cohort with 302 510 women aged 30 to 79 years recruited from 10 regions in China during 2004 to 2008, we assessed the risk of lung cancer death among self-reported never-smoking women who were cancer-free at baseline, in relation to age at menarche, age at menopause, time since menopause, prior use of oral contraceptives (OCP), number of livebirths, breastfeeding and age at first livebirth. Women were followed up to December 31, 2016 with linkage to mortality data. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox regression, adjusting for key confounders including several socio-demographic, environmental and lifestyle factors. Among 287 408 never-smoking women, 814 died from lung cancer with a median follow-up of 10.3 years. Women who had used OCP within 15 years prior to baseline had a significantly higher hazard of lung cancer death compared with never-users: HR = 1.85 (95% CI: 1.14-3.00) and risk increased by 6% with each additional year of use: HR = 1.06 (1.01-1.10). Among parous women, the hazard of lung cancer death increased by 13% with each single livebirth: HR = 1.13 (1.05-1.23); and among post-menopausal women, the risk increased by 2% with each year since menopause: HR = 1.02 (1.01-1.04). These results suggest that reproductive factors which were proxies for lower endogenous oestrogen level, for example, longer duration of OCP use, could play a role in lung cancer development.

Membrane Protein Amuc_1100 Derived from Akkermansia muciniphila Facilitates Lipolysis and Browning via Activating the AC3/PKA/HSL Pathway

Obesity, defined as a disorder of lipid metabolism caused by white fat accumulation, is closely related to the gut microbiota. Akkermansia muciniphila (Akk), one of the most common gut commensals, can reduce fat storage and promote the browning of white adipocytes, alleviating disorders of lipid metabolism. However, which components of Akk produce the effect remain unclear, limiting the application of Akk in the treatment of obesity. Here, we found that the membrane protein Amuc_1100 of Akk decreased formation of lipid droplets and fat accumulation during the differentiation process and stimulated browning in vivo and in vitro. Transcriptomics revealed that Amuc_1100 accelerated lipolysis through upregulation of the AC3/PKA/HSL pathway in 3T3-L1 preadipocytes. Quantitative PCR (qPCR) and Western blotting showed that Amuc_1100 intervention promotes steatolysis and browning of preadipocytes by increasing lipolysis-related genes (AC3/PKA/HSL) and brown adipocyte marker genes (PPARγ, UCP1, and PGC1α) at both the mRNA and protein levels. These findings introduce new insight into the effects of beneficial bacteria and provide new avenues for the treatment of obesity. IMPORTANCE An important intestinal bacterial strain Akkermansia muciniphila contributes to improving carbohydrate and lipid metabolism, thus alleviating obesity symptoms. Here, we find that the Akk membrane protein Amuc_1100 regulates lipid metabolism in 3T3-L1 preadipocytes. Amuc_1100 inhibits lipid adipogenesis and accumulation during the differentiation process of preadipocytes, upregulates the browning-related genes of preadipocytes, and promotes thermogenesis through activation of uncoupling protein-1 (UCP-1), including Acox1 involved in lipid oxidation. Amuc_1100 accelerates lipolysis via the AC3/PKA/HSL pathway, phosphorylating HSL at Ser 660. The experiments illustrated here identify the specific molecules and functional mechanisms of Akk. Therapeutic approaches with Amuc_1100 derived from Akk may help alleviate obesity and metabolic disorders.

Is the association of overweight and obesity with colorectal cancer underestimated? An umbrella review of systematic reviews and meta-analyses

Although high body-mass index (BMI) is associated with increased risk of developing colorectal cancer (CRC), many CRC patients lose weight before diagnosis. BMI is often reported close to diagnosis, which may have led to underestimation or even reversal of direction of the BMI-CRC association. We aimed to assess if and to what extent potential bias from prediagnostic weight loss has been considered in available epidemiological evidence. We searched PubMed and Web of Science until May 2022 for systematic reviews and meta-analyses investigating the BMI-CRC association. Information on design aspects and results was extracted, including if and how the reviews handled prediagnostic weight loss as a potential source of bias. Additionally, we analyzed how individual cohort studies included in the latest systematic review handled the issue. Overall, 18 reviews were identified. None of them thoroughly considered or discussed prediagnostic weight loss as a potential source of bias. The majority (15/21) of cohorts included in the latest review did not exclude any initial years of follow-up from their main analysis. Although the majority of studies reported having conducted sensitivity analyses in which initial years of follow-up were excluded, results were reported very heterogeneously and mostly for additional exclusions of 1-2 years only. Where explicitly reported, effect estimates mostly increased with increasing length of exclusion. The impact of overweight and obesity on CRC risk may be larger than suggested by the existing epidemiological evidence.

Body fatness associations with cancer: evidence from recent epidemiological studies and future directions

This narrative review highlights current evidence linking greater body fatness to risk of various cancers, with focus on evidence from recent large cohort studies and pooled analyses of cohort studies as well as Mendelian randomization studies (which utilized genetic variants associated with body mass index to debrief the causal effect of higher body fatness on cancer risk). This review also provides insights into the biological mechanisms underpinning the associations. Data from both observational and Mendelian randomization studies support the associations of higher body mass index with increased risk of many cancers with the strongest evidence for digestive system cancers, including esophageal, stomach, colorectal, liver, gallbladder, and pancreatic cancer, as well as kidney, endometrial, and ovarian (weak association) cancer. Evidence from observational studies suggests that greater body fatness has contrasting effects on breast cancer risk depending on menopausal status and on prostate cancer risk depending on disease stage. Experimental and Mendelian randomization studies indicate that adiponectin, insulin, and sex hormone pathways play an important role in mediating the link between body fatness and cancer risk. The possible role of specific factors and pathways, such as other adipocytokines and hormones and the gut microbiome in mediating the associations between greater body fatness and cancer risk is yet uncertain and needs investigation in future studies. With rising prevalence of overweight and obesity worldwide, the proportion of cancer caused by excess body fatness is expected to increase. There is thus an urgent need to identify efficient ways at the individual and societal level to improve diet and physical activity patterns to reduce the burden of obesity and accompanying comorbidities, including cancer.

Solid Fuel, Secondhand Smoke, and Lung Cancer Mortality: A Prospective Cohort of 323,794 Chinese Never-Smokers

Rationale: Household air pollution and secondhand tobacco smoke are known carcinogens for lung cancer, but large-scale estimates of the relationship with lung cancer mortality are lacking. Objectives: Using the large-scale cohort China Kadoorie Biobank, we prospectively investigated associations between these two risk factors and lung cancer death among never-smokers. Methods: The Biobank recruited 512,715 adults aged 30-79 years from 10 regions in China during 2004-2008. Self-reported never-smoking participants were followed up to December 31, 2016, with linkage to mortality data. Total duration of exposure to household air pollution was calculated from self-reported domestic solid fuel use. Exposure to secondhand tobacco smoke was ascertained using exposure at home and/or other places. Hazard ratios and 95% confidence intervals for associations between these two exposures and lung cancer death were estimated using Cox regression, adjusting for key confounders. Measurements and Main Results: There were 979 lung cancer deaths among 323,794 never-smoking participants without a previous cancer diagnosis during 10.2 years of follow-up. There was a log-linear positive association between exposure to household air pollution and lung cancer death, with a 4% increased risk per 5-year increment of exposure (hazard ratio = 1.04; 95% confidence interval = 1.01-1.06; P trend = 0.0034), and participants with 40.1-50.0 years of exposure had the highest risk compared with the never-exposed (hazard ratio = 1.53; 95% confidence interval = 1.13-2.07). The association was largely consistent across various subgroups. No significant association was found between secondhand smoke and lung cancer death. Conclusions: This cohort study provides new prospective evidence suggesting that domestic solid fuel use is associated with lung cancer death among never-smokers.

External validation of models for predicting risk of colorectal cancer using the China Kadoorie Biobank

BACKGROUND

In China, colorectal cancer (CRC) incidence and mortality have been steadily increasing over the last decades. Risk models to predict incident CRC have been developed in various populations, but they have not been systematically externally validated in a Chinese population.  This study aimed to assess the performance of risk scores in predicting CRC using the China Kadoorie Biobank (CKB), one of the largest and geographically diverse prospective cohort studies in China.

METHODS

Nine models were externally validated in 512,415 participants in CKB and included 2976 cases of CRC. Model discrimination was assessed, overall and by sex, age, site, and geographic location, using the area under the receiver operating characteristic curve (AUC). Model discrimination of these nine models was compared to a model using age alone. Calibration was assessed for five models, and they were re-calibrated in CKB.

RESULTS

The three models with the highest discrimination (Ma (Cox model) AUC 0.70 [95% CI 0.69-0.71]; Aleksandrova 0.70 [0.69-0.71]; Hong 0.69 [0.67-0.71]) included the variables age, smoking, and alcohol. These models performed significantly better than using a model based on age alone (AUC of 0.65 [95% CI 0.64-0.66]). Model discrimination was generally higher in younger participants, males, urban environments, and for colon cancer. The two models (Guo and Chen) developed in Chinese populations did not perform better than the others. Among the 10% of participants with the highest risk, the three best performing models identified 24-26% of participants that went on to develop CRC.

CONCLUSIONS

Several risk models based on easily obtainable demographic and modifiable lifestyle factor have good discrimination in a Chinese population. The three best performing models have a higher discrimination than using a model based on age alone.

Influencing Factors and Cumulative Risk Analysis of Cervical Lymph Node Metastasis of Papillary Thyroid Microcarcinoma

Objective

To explore the influencing factors and cumulative risk of lymph node metastasis (LNM) in papillary thyroid microcarcinoma (PTMC) patients.

Methods

607 patients confirmed PTMC pathologically after thyroidectomy were enrolled in this retrospective study. The rate of LNM was calculated. Different clinicopathological characteristics were compared in PTMC patients with and without LNM and in different subgroups of LNM, respectively. Correlation between clinicopathological characteristics and LNM was analyzed and the cumulative risk of LNM according to different clinicopathological characteristics was calculated.

Results

(1) There were 228 cases (37.56%) of PTMC combined with LNM. Compared with the non-lymph node metastasis group, the proportion of age <55 years, male, multiple foci, bilateral foci, diameter>0.5cm, extracapsular invasion, HT and intermediate-to-high risk stratification for recurrence of the LNM group was significantly increased (all p<0.05);(2) Multivariate logistic regression analysis showed that age <55years, male, multiple foci, diameter>0.5cm,HT were independently positively correlated with LNM (all p <0.05); (3) Subgroup analysis showed that women aged <55 years combined with HT and aged≥55 years combined with BMI≥25 kg/m² were independently positively associated with LNM; (4) With the increase of the tumor diameter, the cumulative risk of LNM in group of age <55 years, males, and multiple foci increased gradually, and was higher than those of age≥55 years, females and single foci, respectively. (5) Among the 228 cases of LNM, the proportion of lymph nodes (LN) >5 and the positive rate of LN were both higher in male group than that in the female group. The proportion of multiple foci and HT in LLNM group was higher than that in CLNM group (all P<0.05).

Conclusion

Age <55 years, males, multiple foci, diameter >0.5cm and HT were independent risk factors of LNM; HT was an independent risk factor for LNM in female <55 years old, and BMI≥25 kg/m² was an independent risk factor for LNM in female ≥55 years old; The increase of tumor diameter in age <55 years, males, multiple foci, and bilateral foci increased the cumulative risk of LNM, respectively; The number of LNM and the positive rate of LNM were both higher in male, and patients with multiple foci or HT were more likely to develop into LLNM.

Body composition and risk of major gynecologic malignancies: Results from the UK Biobank prospective cohort

OBJECTIVE

To evaluate the association between body composition and subsequent risk of the major gynecologic malignancies.

METHODS

This is a prospective analysis of participants from the UK Biobank. We measured baseline body composition and confirmed cancer diagnosis through linkage to cancer and death registries. We evaluated hazard ratios (HRs) and confidence interval (CIs) with COX models adjusting for potential confounders.

RESULTS

We document 1430 cases of the top three gynecologic malignancies (uterine corpus cancer 847 cases, ovarian cancer 514 cases, and cervical cancer 69 cases) from 245,084 female participants (75,307 were premenopausal and 169,777 were postmenopausal). For premenopausal women, whole body fat-free mass (WBFFM) was associated with an increased risk of uterine corpus cancer (Adjusted HR per unit increase 1.04, 95% CI 1.02-1.06). For postmenopausal women, compared with the first quartile, the fourth quartile of WBFFM and whole body fat mass(WBFM) was associated with 2.16 (95% CI 1.49-3.13) times and 1.89 (95% CI 1.31-2.72) times of increased uterine corpus cancer risk, respectively. Regarding the distribution of body fat mass (FM)/fat-free mass (FFM), FFM distributed in the trunk was associate with increased uterine corpus cancer risk in premenopausal (HR 1.18,95% CI 1.07-1.31) and postmenopausal women (HR 1.13,95% CI 1.09-1.18). Meanwhile, FM/FFM distributed in the limbs present an U-shaped associations with uterine corpus cancer risk. We did not observe any association between aforementioned body composition indices with ovarian or cervical cancer.

CONCLUSION

FM is associated with an increased risk of uterine corpus cancer in postmenopausal women. Meanwhile, FFM is found to be a risk factor for uterine corpus cancer in both premenopausal and postmenopausal women. No association of body composition with ovarian or cervical cancer was observed.

DNA methylome analysis identifies BMI-related epigenetic changes associated with non-small cell lung cancer susceptibility

Background

Body mass index (BMI) has been reported to be inversely associated with incident risk of non‐small cell lung cancer (NSCLC). However, the underlying mechanism is still unclear. This study aimed to investigate the role of DNA methylation in the relationship between BMI and NSCLC.

Methods

We carried out a genome‐wide DNA methylation study of BMI in peripheral blood among 2266 Chinese participants by using Illumina Methylation arrays. For the BMI‐related DNA methylation changes, their associations with NSCLC risk were further analyzed and their mediation effects on BMI‐NSCLC association were also evaluated.

Results

The methylation levels of four CpGs (cg12593793, cg17061862, cg11024682, and cg06500161, annotated to LMNA, ZNF143, SREBF1, and ABCG1, respectively) were found to be significantly associated with BMI. Methylation levels of cg12593793, cg11024682, and cg06500161 were observed to be inversely associated with NSCLC risk [OR (95%CI) =0.22 (0.16, 0.31), 0.39 (0.30, 0.50), and 0.66 (0.53, 0.82), respectively]. Additionally, cg11024682 in SREBF1 and cg06500161 in ABCG1 mediated 45.3% and 19.5% of the association between BMI and decreased NSCLC risk, respectively.

Conclusions

In this study, we identified four DNA methylation sites associated with BMI in the Chinese populations at the genome‐wide significant level. We also found that the BMI‐related methylations of SREBF1 and ABCG1 could mediate about a quintile‐to‐half of the effect of BMI on reduced NSCLC risk, which adds a potential mechanism underlying this association.

Associations of six adiposity-related markers with incidence and mortality from 24 cancers-findings from the UK Biobank prospective cohort study

BACKGROUND

Adiposity is a strong risk factor for cancer incidence and mortality. However, most of the evidence available has focused on body mass index (BMI) as a marker of adiposity. There is limited evidence on relationships of cancer with other adiposity markers, and if these associations are linear or not. The aim of this study was to investigate the associations of six adiposity markers with incidence and mortality from 24 cancers by accounting for potential non-linear associations.

METHODS

A total of 437,393 participants (53.8% women; mean age 56.3 years) from the UK Biobank prospective cohort study were included in this study. The median follow-up was 8.8 years (interquartile range 7.9 to 9.6) for mortality and 9.3 years (IQR 8.6 to 9.9) for cancer incidence. Adiposity-related exposures were BMI, body fat percentage, waist-hip ratio, waist-height ratio, and waist and hip circumference. Incidence and mortality of 24 cancers sites were the outcomes. Cox proportional hazard models were used with each of the exposure variables fitted separately on penalised cubic splines.

RESULTS

During follow-up, 47,882 individuals developed cancer and 11,265 died due to cancer during the follow-up period. All adiposity markers had similar associations with overall cancer incidence. BMI was associated with a higher incidence of 10 cancers (stomach cardia (hazard ratio per 1 SD increment 1.35, (95% CI 1.23; 1.47)), gallbladder (1.33 (1.12; 1.58)), liver (1.27 (1.19; 1.36)), kidney (1.26 (1.20; 1.33)), pancreas (1.12 (1.06; 1.19)), bladder (1.09 (1.04; 1.14)), colorectal (1.10 (1.06; 1.13)), endometrial (1.73 (1.65; 1.82)), uterine (1.68 (1.60; 1.75)), and breast cancer (1.08 (1.05; 1.11))) and overall cancer (1.03 (1.02; 1.04)). All these associations were linear except for breast cancer in postmenopausal women. Similar results were observed when other markers of central and overall adiposity were used. For mortality, nine cancer sites were linearly associated with BMI and eight with waist circumference and body fat percentage.

CONCLUSION

Adiposity, regardless of the marker used, was associated with an increased risk in 10 cancer sites.

Body size and weight change over adulthood and risk of breast cancer by menopausal and hormone receptor status: a pooled analysis of 20 prospective cohort studies

Associations between anthropometric factors and breast cancer (BC) risk have varied inconsistently by estrogen and/or progesterone receptor (ER/PR) status. Associations between prediagnostic anthropometric factors and risk of premenopausal and postmenopausal BC overall and ER/PR status subtypes were investigated in a pooled analysis of 20 prospective cohorts, including 36,297 BC cases among 1,061,915 women, using multivariable Cox regression analyses, controlling for reproductive factors, diet and other risk factors. We estimated dose-response relationships and tested for nonlinear associations using restricted cubic splines. Height showed positive, linear associations for premenopausal and postmenopausal BC risk (6-7% RR increase per 5 cm increment), with stronger associations for receptor-positive subtypes. Body mass index (BMI) at cohort baseline was strongly inversely associated with premenopausal BC risk, and strongly positively-and nonlinearly-associated with postmenopausal BC (especially among women who never used hormone replacement therapy). This was primarily observed for receptor-positive subtypes. Early adult BMI (at 18-20 years) showed inverse, linear associations for premenopausal and postmenopausal BC risk (21% and 11% RR decrease per 5 kg/m2, respectively) with stronger associations for receptor-negative subtypes. Adult weight gain since 18-20 years was positively associated with postmenopausal BC risk, stronger for receptor-positive subtypes, and among women who were leaner in early adulthood. Women heavier in early adulthood generally had reduced premenopausal BC risk, independent of later weight gain. Positive associations between height, baseline (adult) BMI, adult weight gain and postmenopausal BC risk were substantially stronger for hormone receptor-positive versus negative subtypes. Premenopausal BC risk was positively associated with height, but inversely with baseline BMI and weight gain (mostly in receptor-positive subtypes). Inverse associations with early adult BMI seemed stronger in receptor-negative subtypes of premenopausal and postmenopausal BC.

Body size, body composition and endometrial cancer risk among postmenopausal women in UK Biobank

Previous studies on the association of adiposity with endometrial cancer risk have mostly used body mass index (BMI) as the main exposure of interest. Whether more precise measures of body fat, such as body fat percentage and fat mass estimated by bioimpedance analyses, are better indicators of risk than BMI is unknown. The role of central adiposity and fat-free mass in endometrial cancer development remains unclear. We used Cox regression models to estimate hazard ratios (HR) and corresponding 95% confidence intervals (CI) for the associations of various measures of body size/composition with the risk of endometrial cancer among 135 110 postmenopausal women enrolled in UK Biobank. During a mean follow up of 6.8 years, 706 endometrial cancers were diagnosed, with a mean age at diagnosis of 65.5 years. The HRs (95% CIs) for endometrial cancer per 1 SD increase in BMI, body fat percentage and fat mass were broadly comparable, being 1.71 (1.61-1.82), 1.92 (1.75-2.11) and 1.73 (1.63-1.85), respectively. There was an indication of positive association between central adiposity, as reflected by waist circumference (HRper 1-SD increase = 1.08, 95% CI: 1.00-1.17) and waist to hip ratio (HRper 1-SD increase = 1.13, 95% CI: 1.01-1.26), and endometrial cancer risk after accounting for BMI. Fat-free mass was not an independent predictor of risk in this cohort. These findings suggest that body fat percentage and fat mass are not better indicators of endometrial cancer risk than BMI. Further studies are needed to establish whether central adiposity contributes to risk beyond overall adiposity.

The Hemoglobin, Albumin, Lymphocyte, and Platelet (HALP) Score in Patients with Small Cell Lung Cancer Before First-Line Treatment with Etoposide and Progression-Free Survival

BACKGROUND The hemoglobin, albumin, lymphocyte, and platelet (HALP) score is a prognostic factor in patients who have some types of malignant tumors. The aim of this study was to investigate the prognostic significance of the HALP score in patients with small cell lung cancer (SCLC) before first-line treatment with etoposide. MATERIAL AND METHODS A retrospective study included 178 patients with SCLC who received first-line chemotherapy with etoposide between September 2015 and May 2019. The baseline clinical characteristics and blood parameters were recorded. Univariate and multivariate analysis and Kaplan-Meier plots were used to identify the factors associated with progression-free survival (PFS). RESULTS The optimal cut-off values of the HALP score was determined by X-tile software to be 25.8. Univariate and multivariate analysis showed that in 178 patients, the HALP score, body mass index (BMI), and serum albumin levels had no prognostic significance. In the patient age group <65 years, a BMI ≥24 kg/m² was an independent prognostic factor (HR, 1.943; 95% CI, 1.251-3.018) (P=0.003). In the patient age group ≥65 years, a HALP score >25.8 was an independent positive prognostic factor for outcome following first-line treatment with etoposide (HR, 0.483; 95% CI, 0.270-0.865) (P=0.014). CONCLUSIONS In patients <65 years with SCLC who underwent first-line treatment with etoposide, a BMI ≥24 kg/m² an independent prognostic factor, and in patients ≥65 years, a HALP score >25.8 was an independent predictor of improved outcome, associated with increased PFS.