Obesity and risk of pancreatic cancer among postmenopausal women: the Women's Health Initiative (United States). Br J Cancer. 2008;99:527-531. [PMID: 18628761 PMCID: PMC2527801 DOI: 10.1038/sj.bjc.6604487]

Personalized Lifestyle Interventions for Prevention and Treatment of Obesity-Related Cancers: A Call to Action

The increasing global burden of cancer necessitates innovative approaches to prevention and treatment. Lifestyle factors such as diet, physical activity, and smoking significantly contribute to cancer. At the same time, current guidelines are based on a one-size-fits-all approach, which limits their effectiveness across diverse populations. Obesity is a well-documented risk factor for cancer, directly affecting 13 types of cancer. The complex interplay of genetic, metabolic, hormonal, and environmental factors in obesity's etiology highlights the need for more tailored approaches to obesity-related cancers. This perspective article advocates for a shift toward an integrative, personalized approach that considers a variety of intrinsic and extrinsic factors associated with the etiology of obesity-related cancers. Lifestyle-based cancer prevention strategies should be tailored to an individual's biological profile, demographic background, behaviors, and environmental exposures. Following a diagnosis, a comprehensive treatment approach should consider how these genetic, physiological, lifestyle, and environmental factors interact in the onset and progression of the disease while also taking cancer type and stage into account. This approach paves the way for more precise and effective strategies in tackling cancer. Fulfilling collaboration across research, healthcare, and policy sectors is essential to achieve these goals.

Overcoming underestimation of the association of excess weight with pancreatic cancer due to prediagnostic weight loss: Umbrella review of systematic reviews, meta-analyses, and pooled-analyses

Elevated body mass index (BMI) is linked to increased pancreatic cancer (PC) risk. Cancer-associated weight loss can occur years before the malignancy is diagnosed. This might have led to underestimation of the BMI-PC association. However, it is unknown if and to what extent this issue has been considered in previous epidemiological studies. We searched two databases through February 19, 2024 for systematic reviews, meta-analyses, and pooled analyses examining the BMI-PC association. We extracted information on study design with a special focus on the article's examination of prediagnostic weight loss as a potential source of bias, as well as how included cohort studies addressed this concern. Thirteen review articles, meta-analyses, and pooled analyses were identified. Only five (four pooled analyses, one systematic review) considered prediagnostic weight loss in their analyses. Twenty-four of 32 identified cohort studies reported having excluded initial years of follow-up. However, only 13 studies reported results after such exclusions, and effect estimates generally increased with longer periods of exclusion. We conclude that the association of overweight and obesity with PC risk is likely larger than suggested by published epidemiological evidence. Future studies should pay careful attention to avoid or minimize potential bias resulting from prediagnostic weight loss.

Reevaluating the fraction of cancer attributable to excess weight: overcoming the hidden impact of prediagnostic weight loss

OBJECTIVE

To evaluate the magnitude of the potential underestimation of the proportion of cancer cases attributable to excess weight, known as population attributable fraction (PAF), due to potential bias from prediagnostic weight loss already present at baseline of cohort studies and to overcome it as much as possible.

METHODS

Data from the UK Biobank cohort participants aged 40-69 without prior cancer diagnosis were analyzed. We assessed the magnitude of associations of excess weight with the incidence of obesity-related cancers combined, and separately for gastrointestinal (GI) and other cancers. Using multivariable Cox proportional hazards models, hazard ratios (HR) and their 95% confidence intervals (CI), and PAFs for excess weight at baseline were estimated for various periods of time after weight measurements.

FINDINGS

Of 458,660 participants, 20,218 individuals developed obesity-related cancers during a median 11.0-year follow-up, comprising 8,460 GI, and 11,765 non-GI cancers. PAFs were much higher for cancers occurring more than four years after recruitment than for cancers occurring within the initial four years: 17.7% versus 7.2%, 21.4% versus 11.7% for GI, non-GI and all obesity-related cancers combined, respectively. With respect to total cancer (including cancers with no established relationship with excess weight), PAFs were estimated as 5.1% and 8.8% for the 0-4 and 4-14-year periods of follow-up.

CONCLUSION

The proportion of cancers attributable to excess weight is likely substantially larger than previously estimated based on cohort studies with short follow-up time or no or only limited exclusion of the early years of follow-up from the analyses.

Abdominal obesity and digestive system cancer: a systematic review and meta-analysis of prospective studies

BACKGROUND

The diagnostic criteria for abdominal obesity are usually waist circumference or waist-to-hip ratio. The magnitude of the risks for cancers of the digestive system and abdominal obesity is unknown. To assess whether abdominal obesity increases the risk of digestive cancer, we conducted a systematic review and meta-analysis of prospective cohort studies in a database.

METHODS

PubMed, Embase, and Web of Science databases were searched from their inception to December 2022. The 9-star Newcastle Ottawa Scale was used to assess  study quality. Pooled relative risks and 95% confidence intervals were calculated using fixed or random effect models respectively. The stability of the results was explored by one-by-one exclusion. Subgroup analysis was conducted to explore sources of heterogeneity. Publication bias was evaluated by Begg's and Egger's tests.

RESULTS

A total of 43 cohort studies were included. There were 42 and 31 studies in the meta-analysis of waist circumference and waist-to-hip ratio on digestive system cancer, respectively. The results of the meta-analysis revealed that the greater waist circumference and waist-to-hip ratio were correlated with increased incidence of digestive system cancers: waist circumference: RR 1.48, 95% CI 1.38-1.59, p < 0.001; waist-to-hip ratio: RR 1.33, 95% CI 1.28-1.38, p = 0.001. Subgroup analysis by cancer type showed that higher WC and WHR would increase the prevalence of LC, PC, GC, EC, and CRC. The sensitivity analysis was conducted by a one-by-one elimination method, and the results of the meta-analysis remained stable. It is proved that the results were robust by the trim-and-fill method.

CONCLUSIONS

There was evidence to suggest that abdominal obesity increased the incidence of digestive cancer, it is necessary to take appropriate measures to reduce abdominal obesity. Waist circumference and waist-to-hip ratio may be better predictors of digestive system cancers. However, the association between waist circumference and digestive system cancer was greater, so more attention should be paid to measuring abdominal obesity with waist circumference.

The underexplored links between cancer and the internal body climate: Implications for cancer prevention and treatment

In order to effectively manage and cure cancer we should move beyond the general view of cancer as a random process of genetic alterations leading to uncontrolled cell proliferation or simply a predictable evolutionary process involving selection for traits that increase cell fitness. In our view, cancer is a systemic disease that involves multiple interactions not only among cells within tumors or between tumors and surrounding tissues but also with the entire organism and its internal "milieu". We define the internal body climate as an emergent property resulting from spatial and temporal interactions among internal components themselves and with the external environment. The body climate itself can either prevent, promote or support cancer initiation and progression (top-down effect; i.e., body climate-induced effects on cancer), as well as be perturbed by cancer (bottom-up effect; i.e., cancer-induced body climate changes) to further favor cancer progression and spread. This positive feedback loop can move the system towards a "cancerized" organism and ultimately results in its demise. In our view, cancer not only affects the entire system; it is a reflection of an imbalance of the entire system. This model provides an integrated framework to study all aspects of cancer as a systemic disease, and also highlights unexplored links that can be altered to both prevent body climate changes that favor cancer initiation, progression and dissemination as well as manipulate or restore the body internal climate to hinder the success of cancer inception, progression and metastasis or improve therapy outcomes. To do so, we need to (i) identify cancer-relevant factors that affect specific climate components, (ii) develop 'body climate biomarkers', (iii) define 'body climate scores', and (iv) develop strategies to prevent climate changes, stop or slow the changes, or even revert the changes (climate restoration).

Sustained Weight Loss, Weight Cycling, and Weight Gain During Adulthood and Pancreatic Cancer Incidence in the Women's Health Initiative

Pancreatic cancer (PC) is the fourth leading cause of cancer mortality among women in the United States. Obesity is positively associated with PC risk. Current health recommendations focus on weight maintenance for healthy-weight individuals and weight loss for overweight/obese individuals; however, little research has assessed associations between PC risk and changes in weight throughout the life course. Using prospective cohort study data, we examined the relationship between baseline adulthood weight patterns self-reported between 1993 and 1998 and PC risk in 136,834 postmenopausal women with 873 incident PC cases through September 30, 2015, in the Women's Health Initiative. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional hazards models, adjusting for age, smoking habits, heavy alcohol consumption, and body mass index. Compared with women with stable weight, no significant associations were found between steady weight gain (HR = 1.01, 95% CI: 0.83, 1.22), sustained weight loss (HR = 1.26, 95% CI: 0.85, 1.87), or weight cycling patterns (HR = 1.08, 95% CI: 0.89, 1.30) and PC. Results were similar when the outcome definition was restricted to pancreatic adenocarcinoma cases. Overall, we did not find evidence to suggest that weight changes in adulthood significantly impact PC risk among postmenopausal women.

Visceral Adiposity and Cancer: Role in Pathogenesis and Prognosis

The prevalence of being overweight and obese has been expanded dramatically in recent years worldwide. Obesity usually occurs when the energetic introit overtakes energy expenditure from metabolic and physical activity, leading to fat accumulation mainly in the visceral depots. Excessive fat accumulation represents a risk factor for many chronic diseases, including cancer. Adiposity, chronic low-grade inflammation, and hyperinsulinemia are essential factors of obesity that also play a crucial role in tumor onset. In recent years, several strategies have been pointed toward boundary fat accumulation, thus limiting the burden of cancer attributable to obesity. While remodeling fat via adipocytes browning seems a tempting prospect, lifestyle interventions still represent the main pathway to prevent cancer and enhance the efficacy of treatments. Specifically, the Mediterranean Diet stands out as one of the best dietary approaches to curtail visceral adiposity and, therefore, cancer risk. In this Review, the close relationship between obesity and cancer has been investigated, highlighting the biological mechanisms at the basis of this link. Finally, strategies to remodel fat, including browning and lifestyle interventions, have been taken into consideration as a major perspective to limit excess body weight and tumor onset.

Visceral obesity and incident cancer and cardiovascular disease: An integrative review of the epidemiological evidence

Evidence shows a strong relationship between obesity, cancer and cardiovascular disease (CVD) risk. However, there is not enough evidence of the role of visceral obesity on both CVD and cancer. Visceral obesity may be more pro-oncogenic than total body fat. Therefore, it is important to know whether abdominal obesity can lead to both CVD and cancer. The present integrative review aimed at evaluating epidemiological evidence on the potential connection of visceral obesity in the occurrence of cancer and CVD. The following databases were searched: SCOPUS, PubMed, Science Direct, Lilacs, SciELO, Google Scholar, Web of Science, Scopus and ProQuest. The presence of visceral obesity can increase the risk of some specific cancer types, but there is controversial evidence about CVD risk based on sex-specific and ageing analyses. There is enough evidence that visceral obesity increases the risk of colorectal, pancreatic and gastro-oesophageal cancer. However, for some types of cancer such as breast, endometrial and renal, visceral obesity is a risk only in post-menopausal women. Regarding prostate cancer, the evidence is controversial. Despite the risk of visceral obesity being consistently associated with CVD in adults, this association disappears in sex-specific and older adults analyses. Moreover, in older adults, the results are controversial due to the use of different measures such as waist circumference and visceral adipose tissue. However, the evidence showing visceral obesity as a risk factor to CVD remains controversial. Sex differences, ageing and body mass index (BMI) category can potentially modify this association. Therefore, further epidemiological studies with analyses stratified by sex and samples including older adults aged 65 and older are needed.

Pancreatic cancer and obesity: epidemiology, mechanism, and preventive strategies

The prevalence of obesity has seen a global increase in the past decades, escalating to one of the major epidemiological challenges today. Global economic growth has caused changes in dietary and physical activity patterns fueling obesity across age, gender, and income groups. The implications are many, as obesity has been associated with numerous serious health conditions, ultimately affecting morbidity and mortality. There is a growing recognition of the risk a high body mass index confers on the development and outcome of several malignancies, including pancreatic cancer. Pancreatic cancer is a highly lethal disease with exceptionally poor outcome, with incidences rising worldwide. Due to vague symptoms and no screening recommendations, a vast majority of patients are diagnosed at late stages, with already advanced disease and no opportunity for surgical intervention. Obesity mediates risk for pancreatic cancer through insufficiently understood mechanisms, possibly including inflammation and hormonal misbalance. As excess abdominal adiposity is among the few modifiable risk factors for pancreatic cancer onset, enduring weight loss could manifest an effective preventive measure. Lifestyle modifications on a population level aimed to reduce obesity could also scale down the grim pancreatic cancer rates. In cases when these measures alone are insufficiently effective, bariatric surgery can be an advantageous alternative. Extremely obese patients exhibit many health benefits following bariatric surgery along with weight loss, consequently reducing the chances of pancreatic cancer, especially if additionally adopting healthy lifestyle habits.

Remnant pancreatic volume as an indicator of poor prognosis in pancreatic cancer patients after resection

BACKGROUND

Remnant pancreatic volume (RPV) is a well-known marker for short-term outcomes in pancreatic cancer patients after resection. However, in terms of the long-term outcomes, the significance of the RPV value remains unclear. Here, we address whether the RPV value is a predictor of the long-term outcomes in pancreatic cancer patients after resection by comparing various cancer-, patient-, and surgery-related prognostic factors and systemic inflammatory response markers in a retrospective cohort.

METHODS

The RPV was measured on a three-dimensional (3D) image, revealing the actual pancreatic parenchymal remnant volume. Ninety-one patients who underwent pancreaticoduodenectomy were retrospectively enrolled. We divided the cohort into high- and low-RPV groups based on a cut-off value (>31.5 cm³, n = 66 and ≤31.5 cm³, n = 25, respectively). The median survival times (MSTs) were compared between the two groups. Using multivariate analysis, the RPV and other well-known prognostic factors were independently assessed.

RESULTS

The MSTs (days) were significantly different between the two groups (high, 823 vs. low, 482, p = 0.001). Multivariate analysis identified the RPV (≤31.5 cm³) (hazard ratio [HR], 2.015; p = 0.011), lymph node metastasis (HR, 8.415; p = 0.002), lack of adjuvant chemotherapy (HR, 5.352; p < 0.001), stage III/IV disease (HR, 2.352; p = 0.029), and pathological fibrosis (HR, 1.771; p = 0.031) as independent prognostic factors.

CONCLUSIONS

The present study suggests that the RPV value is also useful for predicting long-term outcomes in pancreatic cancer patients after resection.

Associations of metabolic syndrome and C-reactive protein with mortality from total cancer, obesity-linked cancers and breast cancer among women in NHANES III

Although metabolic syndrome (MetS) is a prognostic factor for cancer occurrence, the association of MetS and cancer mortality remains unclear. The purpose of this study was to evaluate whether MetS, components of MetS and C-reactive protein (CRP) are associated with cancer mortality in women. A total of 400 cancer deaths, with 140 deaths from obesity-linked-cancers (OLCas), [breast (BCa), colorectal, pancreatic and endometrial], linked through the National Death Index, were identified from 10,104 eligible subjects aged ≥18 years. Cox proportional hazards regression was used to estimate multivariable-adjusted hazard ratios (HR) for cancer mortality. MetS was associated with increased deaths for total cancer [HR = 1.33, 95% confidence interval (CI) 1.04-1.70] and BCa [HR = 2.1, 95% CI, 1.09-4.11]. The risk of total cancer [HR = 1.7, 95% CI, 1.12-2.68], OLCas [HR = 2.1, 95% CI, 1.00-4.37] and BCa [HR = 3.8, 95% CI, 1.34-10.91] mortality was highest for women with all MetS components abnormal, compared to those without MetS. Linear associations of blood-pressure [HR = 2.5, 1.02-6.12, Quartile (Q) 4 vs Q1, p trend = 0.004] and blood-glucose [HR = 2.2, 1.04-4.60, Q4 vs. Q1, p trend = 0.04] with total-OLCas mortality were observed. A threefold increased risk of BCa mortality was observed for women with enlarged waist circumference, ≥100.9 cm, [HR = 3.5, 1.14-10.51, p trend = 0.008] and in those with increased blood glucose, ≥101 mg/dL, [HR = 3.2, 1.11-9.20, p trend = 0.03] compared to those in Q1. None of the components of MetS were associated with total-cancer mortality. CRP was not associated with cancer mortality. In conclusion, MetS is associated with total-cancer and breast-cancer mortality, with waist circumference, blood pressure and blood glucose as independent predictors of OLCas and BCa mortality.

Cachexia, and not obesity, prior to pancreatic cancer diagnosis worsens survival and is negated by chemotherapy

Background

Although advanced pancreatic ductal adenocarcinoma (PDAC) is characterized by progressive weight loss and nutritional deterioration, the effect of cancer cachexia and body mass index (BMI) at diagnosis on survival remains unclear.

Methods

We retrospectively evaluated a prospectively collected internal cancer registry of PDAC cases from 2006-2014 at the Kaiser Permanente Medical Center. Cancer cachexia was defined as weight loss greater than 5% over the 6 months prior to diagnosis. Multivariate cox proportional hazards regression was used to assess the influence of cachexia on survival. To evaluate effect measure modification of this relationship, we performed additional analyses stratified by race, BMI class, stage, receipt of surgery and receipt of chemotherapy. We tested for heterogeneity by fitting models with an interaction term for cachexia and the modifying variable.

Results

Of the 977 patients, 611 (63%) were identified with cachexia. Cachexia in PDAC patients was prevalent across all stages of disease and BMI classes. Patients with cachexia had lower survival (median 4.3 months, IQR 1.7-10.0) compared to those without cachexia (median 5.2 months, IQR 2.0-10.6), log-rank P=0.03. In this analysis BMI at diagnosis was not associated with survival. In the multivariate Cox regression, cachexia was independently associated with decreased overall survival (HR 1.24, CI: 1.06-1.45, P=0.01). However, the effect of cachexia on survival outcomes was modified by receipt of chemotherapy. Cachectic patients who did not receive chemotherapy had a 40% increase in risk of death compared to non-cachectic patients (HR 1.40, CI: 1.12-1.75), while those receiving chemotherapy were unaffected by cachexia (HR 1.04, CI: 0.82-1.32, P_interaction=0.01).

Conclusions

In the largest cohort of pancreatic cancer patients examined to date, cachexia and not obesity is independently associated with worse survival in PDA and its effect is negated by systemic chemotherapy.

Low-fat Dietary Pattern and Pancreatic Cancer Risk in the Women's Health Initiative Dietary Modification Randomized Controlled Trial

Background

Observational studies suggest that diet may influence pancreatic cancer risk. We investigated the effect of a low-fat dietary intervention on pancreatic cancer incidence.

Methods

The Women's Health Initiative Dietary Modification (WHI-DM) trial is a randomized controlled trial conducted in 48 835 postmenopausal women age 50 to 79 years in the United States between 1993 and 1998. Women were randomly assigned to the intervention group (n = 19 541), with the goal of reducing total fat intake and increasing intake of vegetables, fruits, and grains, or to the usual diet comparison group (n = 29 294). The intervention concluded in March 2005. We evaluated the effect of the intervention on pancreatic cancer incidence with the follow-up through 2014 using the log-rank test and multivariable Cox proportional hazards regression model. All statistical tests were two-sided.

Results

In intention-to-treat analyses including 46 200 women, 92 vs 165 pancreatic cancer cases were ascertained in the intervention vs the comparison group (P = .23). The multivariable hazard ratio (HR) of pancreatic cancer was 0.86 (95% confidence interval [CI] = 0.67 to 1.11). Risk was statistically significantly reduced among women with baseline body mass indexes (BMIs) of 25 kg/m2 or higher (HR = 0.71, 95% CI = 0.53 to 0.96), but not among women with BMIs of less than 25 kg/m2 (HR = 1.62, 95% CI = 0.97 to 2.71, Pinteraction = .01).

Conclusions

A low-fat dietary intervention was associated with reduced pancreatic cancer incidence in women who were overweight or obese in the WHI-DM trial. Caution needs to be taken in interpreting the findings based on subgroup analyses.

Incidence of pancreatic cancer is dramatically increased by a high fat, high calorie diet in KrasG12D mice

Epidemiologic data has linked obesity to a higher risk of pancreatic cancer, but the underlying mechanisms are poorly understood. To allow for detailed mechanistic studies in a relevant model mimicking diet-induced obesity and pancreatic cancer, a high-fat, high-calorie diet (HFCD) was given to P48^+/Cre;LSL-KRAS^G12D (KC) mice carrying a pancreas-specific oncogenic Kras mutation. The mice were randomly allocated to a HFCD or control diet (CD). Cohorts were sacrificed at 3, 6, and 9 months and tissues were harvested for further analysis. Compared to CD-fed mice, HFCD-fed animals gained significantly more weight. Importantly, the cancer incidence was remarkably increased in HFCD-fed KC mice, particularly in male KC mice. In addition, KC mice fed the HFCD showed more extensive inflammation and fibrosis, and more advanced PanIN lesions in the pancreas, compared to age-matched CD-fed animals. Interestingly, we found that the HFCD reduced autophagic flux in PanIN lesions in KC mice. Further, exome sequencing of isolated murine PanIN lesions identified numerous genetic variants unique to the HFCD. These data underscore the role of sustained inflammation and dysregulated autophagy in diet-induced pancreatic cancer development and suggest that diet-induced genetic alterations may contribute to this process. Our findings provide a better understanding of the mechanisms underlying the obesity-cancer link in males and females, and will facilitate the development of interventions targeting obesity-associated pancreatic cancer.

Evolving treatment landscape for early and advanced pancreatic cancer

Pancreatic ductal adenocarcinoma is an infrequent cancer with a high disease related mortality rate, even in the context of early stage disease. Until recently, the rate of death from pancreatic cancer has remained largely similar whereby gemcitabine monotherapy was the mainstay of systemic treatment for most stages of disease. With the discovery of active multi-agent chemotherapy regimens, namely FOLFIRINOX and gemcitabine plus nab-paclitaxel, the treatment landscape of pancreatic cancer is slowly evolving. FOLFIRINOX and gemcitabine plus nab-paclitaxel are now considered standard first line treatment options in metastatic pancreatic cancer. Studies are ongoing to investigate the utility of these same regimens in the adjuvant setting. The potential of these treatments to downstage disease is also being actively examined in the locally advanced context since neoadjuvant approaches may improve resection rates and surgical outcomes. As more emerging data become available, the management of pancreatic cancer is anticipated to change significantly in the coming years.

Proteomic Analysis, Immune Dysregulation, and Pathway Interconnections with Obesity

Proteomic studies can offer information on hundreds to thousands of proteins and potentially provide researchers with a comprehensive understanding of signaling response during stress and disease. Large data sets, such as those obtained in high-dimensional proteomic studies, can be leveraged for pathway analysis to discover or describe the biological implications of clinical disease states. Obesity is a worldwide epidemic that is considered a risk factor for numerous other diseases. We performed analysis on plasma proteomic data from 3 separate sample sets of postmenopausal women to identify the pathways that are altered in subjects with a high body mass index (BMI) compared to normal BMI. We found many pathways consistently and significantly associated with inflammation dysregulated in plasma from obese/overweight subjects compared to plasma from normal BMI subjects. These pathways indicate alterations of soluble inflammatory regulators, cellular stress, and metabolic dysregulation. Our results highlight the importance of high-dimensional pathway analysis in complex diseases as well as provide information on the interconnections between pathways that are dysregulated with obesity. Specifically, overlap of obesity related pathways with those activated during cancer and infection could help describe why obesity is a risk factor for disease and help devise treatment options that mitigate its effect.

Platelet × CRP Multiplier Value as an Indicator of Poor Prognosis in Patients With Resectable Pancreatic Cancer

OBJECTIVE

Thrombocytosis in patients with various cancers has been considered a parameter for poor prognosis; however, its contribution to pancreatic cancer remains controversial.

METHODS

Potential preoperative prognostic parameters (platelets, neutrophils, lymphocytes, the platelet-lymphocyte ratio, the neutrophil-lymphocyte ratio, the serum C-reactive protein [CRP], and carbohydrate antigen 19-9) were retrospectively analyzed in 95 patients with pancreatic cancer. Cutoff values were defined according to receiver operating characteristic curve analysis, and median survival times (MSTs) were compared.

RESULTS

Median survival times (days) significantly differed according to platelet count (high [552] vs low [735], P = 0.017), CRP (high [471] vs low [750], P = 0.001), and carbohydrate antigen 19-9 level (high [639] vs low [765], P = 0.021), whereas there was no difference in the platelet-lymphocyte ratio and the neutrophil-lymphocyte ratio. Multivariate analysis identified thrombocytosis (hazard ratio, 2.015) and CRP level (hazard ratio, 1.771) as independent prognostic factors. The combinatory effects of platelets and the inflammatory response using a platelet × CRP multiplier value could effectively distinguished the MSTs (days) of patients with pancreatic cancer (high [482] vs low [812], P < 0.001).

CONCLUSIONS

Thrombocytosis and CRP influenced pancreatic cancer patient prognosis. Platelet × CRP multiplier is assumed as a useful parameter that reflects the contribution of activated platelets to cancer progression.

Exploring the metabolic syndrome: Nonalcoholic fatty pancreas disease

After the first description of fatty pancreas in 1933, the effects of pancreatic steatosis have been poorly investigated, compared with that of the liver. However, the interest of research is increasing. Fat accumulation, associated with obesity and the metabolic syndrome (MetS), has been defined as "fatty infiltration" or "nonalcoholic fatty pancreas disease" (NAFPD). The term "fatty replacement" describes a distinct phenomenon characterized by death of acinar cells and replacement by adipose tissue. Risk factors for developing NAFPD include obesity, increasing age, male sex, hypertension, dyslipidemia, alcohol and hyperferritinemia. Increasing evidence support the role of pancreatic fat in the development of type 2 diabetes mellitus, MetS, atherosclerosis, severe acute pancreatitis and even pancreatic cancer. Evidence exists that fatty pancreas could be used as the initial indicator of "ectopic fat deposition", which is a key element of nonalcoholic fatty liver disease and/or MetS. Moreover, in patients with fatty pancreas, pancreaticoduodenectomy is associated with an increased risk of intraoperative blood loss and post-operative pancreatic fistula.

Influence of Body Mass Index and Albumin on Perioperative Morbidity and Clinical Outcomes in Resected Pancreatic Adenocarcinoma

Obesity is a known risk factor for PDA and recent reports suggest obesity has a negative impact on clinical outcomes in patients with PDA. Pretreatment body mass index (BMI) and serum albumin (SA) have been shown to be associated with worse overall survival in patients with advanced and metastatic PDA. However, minimal data exists on the impact of BMI and SA on perioperative and long-term clinical outcomes in patients with early-stage resected PDA. Herein, we report on the impact of these variables on perioperative clinical outcomes, overall survival (OS) and disease free survival (DFS) in patients with resected PDA. With IRB approval, we evaluated 1,545 patients with PDA treated at a single institution from 2007–2013 and identified 106 patients who underwent upfront resection with curative intent. BMI and SA were calculated preoperatively and at the time of last clinical evaluation. Influence of preoperative BMI, SA, change in either variable, and influence of other clinical and pathologic variables on perioperative morbidity and mortality was assessed. The impact of these variables on DFS and OS was assessed with cox regression modeling and ANOVA. Actuarial estimates for DFS and OS were calculated using Kaplan-Meier methods. Median follow up time was 16 months (3–89). Mean age was 68 years. Median survival was 14 months (3–65) and median time to recurrence was 11 months (1–79). Length of hospital stay was associated with BMI (p = .023), change in BMI (p = .003) and SA (p = .004). Post-operative transfusion rate was associated with SA (p = .021). There was a strong correlation between BMI change and positive margin (p = .04) and lymph node status (p = .01). On multivariate analysis, change in SA (p = .03) and node positivity (p = .008) were associated with decreased DFS. Additionally, preoperative SA (p = .023), node positivity (p = .026) and poor differentiation (p = .045) were associated with worse OS on multivariate analysis. Low preoperative SA was associated with worse DFS and OS in patients with resected PDA. Lower BMI and SA were associated with longer post-operative hospital stay. Our study is one of the first to describe how pre-operative BMI and SA and post-operative changes in these variables impact clinical and perioperative outcomes. This data supports nutritional status and weight loss as predictors of outcome in resected pancreatic cancer patients and warrants further prospective investigation.

Adult weight gain and adiposity-related cancers: a dose-response meta-analysis of prospective observational studies

BACKGROUND

Adiposity, measured by body mass index, is implicated in carcinogenesis. While adult weight gain has diverse advantages over body mass index in measuring adiposity, systematic reviews on adult weight gain in relation to adiposity-related cancers are lacking.

METHODS

PubMed and Embase were searched through September 2014 for prospective observational studies investigating the relationship between adult weight gain and the risk of 10 adiposity-related cancers. Dose-response meta-analyses were performed using a random-effects model to estimate summary relative risk (RR) and 95% confidence interval (CI) for each cancer type. All statistical tests were two-sided.

RESULTS

A total of 50 studies were included. For each 5 kg increase in adult weight gain, the summary relative risk was 1.11 (95% CI = 1.08 to 1.13) for postmenopausal breast cancer among no- or low-hormone replacement therapy (HRT) users, 1.39 (95% CI = 1.29 to 1.49) and 1.09 (95% CI = 1.02 to 1.16) for postmenopausal endometrial cancer among HRT nonusers and users, respectively, 1.13 (95% CI = 1.03 to 1.23) for postmenopausal ovarian cancer among no or low HRT users, 1.09 (95% CI = 1.04 to 1.13) for colon cancer in men. The relative risk of kidney cancer comparing highest and lowest level of adult weight gain was 1.42 (95% CI = 1.11 to 1.81). Adult weight gain was unrelated to cancers of the breast (premenopausal women, postmenopausal HRT users), prostate, colon (women), pancreas, and thyroid. An increase in risk associated with adult weight gain for breast cancer was statistically significantly greater among postmenopausal women (P(heterogeneity) = .001) and HRT nonusers (P(heterogeneity) = .001); that for endometrial cancer was alike among HRT nonusers (P(heterogeneity) = .04).

CONCLUSIONS

Avoiding adult weight gain itself may confer protection against certain types of cancers, particularly among HRT nonusers.

The impact of body mass index dynamics on survival of patients with advanced pancreatic cancer receiving chemotherapy

CONTEXT

High body mass index (BMI) is linked to an increased risk of developing pancreatic cancer (PC). However, in patients with advanced PC (APC), especially those receiving palliative chemotherapy, the impact of BMI on survival has not been investigated fully.

OBJECTIVES

To assess changes in BMI during the course of APC and their impact on patient survival, specifically for those receiving palliative chemotherapy.

METHODS

Consecutive patients with APC, all of whom were treated with palliative chemotherapy, were enrolled during 2003-2010. Clinical characteristics and prognoses were analyzed.

RESULTS

A total of 425 patients participated (median age, 60.1 years). At diagnosis of APC, patients' BMI distribution of patients was as follow: <18.5 (45, 10.6%); 18.5-19.9 (67, 15.8%); 20.0-22.4 (156, 36.7%); 22.5-24.9 (107, 25.2%); 25.0-29.9 (49, 11.5%); and ≥ 30.0 (1, 0.2%). Median overall survival (OS) was 8.1 months (95% confidence interval 7.2, 9.1). Precancer BMI and baseline BMI (at diagnosis) had no impact on OS. Weight loss at diagnosis (precancer weight minus weight at diagnosis) and weight loss during first-line chemotherapy (both stipulated as BMI change ≥ 1) were associated with shortened OS (hazard ratio, 1.300; P = 0.012 and hazard ratio, 1.367; P = 0.010, respectively).

CONCLUSION

In patients with APC undergoing palliative chemotherapy, decreases in BMI at APC diagnosis and during chemotherapy are more hazardous for OS than precancer BMI or baseline BMI (at diagnosis) as absolute values. Further studies are needed to validate this finding and investigate strategies to maintain BMI during chemotherapy in this setting.

Overweight, obesity and endometrial cancer risk: results from a systematic review and meta-analysis

AIM

Findings from recent studies suggest that obesity may be associated with an increased risk of endometrial cancer, but several earlier studies were less conclusive. Here we strive to estimate this relationship in a meta-analysis of published data.

METHODS

We searched Pubmed and Embase for studies on body mass index and the risk of endometrial cancer, published from 1989 to 2011. Data were independently extracted and analyzed using random or fixed effects meta-analysis depending on the degree of heterogeneity.

RESULTS

Seven cohort studies and 11 case-control studies were included in the meta-analysis. Overall, the conditions of excess body weight ([EBW] defined as body mass index [BMI] ≥25 kg/m²), obesity (BMI ≥30 kg/m²) and overweight (25< BMI <30 kg/m²) were associated with an increased risk of endometrial cancer (relative risk [RR] for EBW=1.62, 95% confidence interval [CI], 1.39-1.89; for obesity RR=2.54, 95% CI, 2.11-3.06; for overweight RR=1.32, 95% CI, 1.16-1.50). Subgroup analyses showed that the positive associations were independent of study design, geographic locations, self-reported BMI, alcohol use, smoking habit, history of diabetes, hormone therapy, age at menarche, age at menopause, parity, and age at first full term pregnancy. However, there was no statistically significant association between EBW and endometrial cancer risk for measured BMI (for EBW RR=1.29, 95% CI, 0.66-2.53).

CONCLUSIONS

The findings from this meta-analysis strongly support that the conditions of EBW, overweight, and obesity are all associated with an increased risk of endometrial cancer. Also, the strength of the association increases with increasing BMI.

Obesity and pancreatic cancer

BACKGROUND

Pancreatic cancer is an invariably fatal malignancy. Cigarette smoking and diabetes are established risk factors, but over the last two decades studies have shown that excess adiposity is an additional independent risk factor with 30-50% of cases thought to be attributed to nutritional factors. The aim of this narrative review is to analyze all the epidemiological evidence on the topic and possible pathophysiology.

METHODS

We searched PubMed, Embase, Cochrane Library and Medline, and all available evidence was included. We firstly analyze meta- and pooled analysis. Then we discuss individual studies to identify sources of discrepancies between studies and attempt to delineate pathophysiology.

RESULTS

It is estimated that obese individuals have a relative risk (RR) ranging between 1.19 and 1.47, when compared with those of normal weight, regardless of diabetes or smoking status. No significant differences were found between gender.

CONCLUSION

There is a measurable increased risk of developing pancreatic cancer in obese individuals, and excess adiposity is related to the condition with a "dose-response" curve. Hyperinsulinemia and possibly hyperestrogenism secondary to a metabolic syndrome, and independently from diabetes status, appear to be the key elements of the pathogenesis in pancreatic cancer secondary to excess body fat. Increased efforts should therefore be made in tackling the epidemic levels of obesity in the Western world countries.

Body mass index and risk of pancreatic cancer in a Chinese population

Few studies have examined the association between body mass index (BMI: kg/m²) and pancreatic cancer risk in Asian populations. We examined this relationship in 51,251 Chinese men and women aged 45–74 who enrolled between 1993 and 1998 in the population based, prospective Singapore Chinese Health Study. Data were collected through in-person interviews. By December 31, 2011, 194 cohort participants had developed pancreatic cancer. A Cox proportional hazards model was used to estimate hazard ratios (HR) and their 95% confidence intervals (95% CI). We hypothesized the association between BMI and pancreatic cancer risk may vary by smoking status (ever v. never) and there was evidence for this as the interaction between BMI and smoking status was significant (p = 0.018). Among ever smokers, being classified as underweight (BMI <18.5 kg/m²), was associated with a significantly elevated risk of pancreatic cancer relative to smokers with a BMI of 21.5–24.4 kg/m² (HR = 1.99, 95% CI  =  1.03–3.84). This association was strengthened after exclusion of the first three years of follow-up time. Among never smokers, there was no association between BMI and pancreatic cancer risk. However, after excluding pancreatic cancer cases and person-years in the first three years of follow-up, never smokers with a BMI ≥ 27.5 kg/m² showed a suggestive increased risk of pancreatic cancer relative to never smokers with a BMI of 21.5–24.4 kg/m² (HR  =  1.75, 95% CI  =  0.93–3.3). In conclusion, Singaporean Chinese who were underweight with a history of smoking had an increased risk of developing pancreatic cancer, whereas there was no significant association between BMI and pancreatic cancer in never smokers.

Metabolic syndrome, obesity, and gastrointestinal cancer

METABOLIC SYNDROME IS A CLUSTER OF METABOLIC ABNORMALITIES AND IS DEFINED AS THE PRESENCE OF THREE OR MORE OF THE FOLLOWING FACTORS: increased waist circumference, elevated triglycerides, low high-density lipoprotein cholesterol, high blood pressure, and high fasting glucose. Obesity, which is accompanied by metabolic dysregulation often manifested in the metabolic syndrome, is an established risk factor for many cancers. Adipose tissue, particularly visceral fat, is an important metabolic tissue as it secretes systemic factors that alter the immunologic, metabolic, and endocrine milieu and also promotes insulin resistance. Within the growth-promoting, proinflammatory environment of the obese state, cross-talk between macrophages, adipocytes, and epithelial cells occurs via obesity-associated hormones, adipocytokines, and other mediators that may enhance cancer risk and progression. This paper synthesizes the evidence on key molecular mechanisms underlying the obesity-cancer link.

American Cancer Society Guidelines on nutrition and physical activity for cancer prevention: reducing the risk of cancer with healthy food choices and physical activity

The American Cancer Society (ACS) publishes Nutrition and Physical Activity Guidelines to serve as a foundation for its communication, policy, and community strategies and, ultimately, to affect dietary and physical activity patterns among Americans. These Guidelines, published approximately every 5 years, are developed by a national panel of experts in cancer research, prevention, epidemiology, public health, and policy, and they reflect the most current scientific evidence related to dietary and activity patterns and cancer risk. The ACS Guidelines focus 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. The ACS Guidelines are 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 2010 Dietary Guidelines for Americans and the 2008 Physical Activity Guidelines for Americans.

Body mass index, abdominal fatness and pancreatic cancer risk: a systematic review and non-linear dose-response meta-analysis of prospective studies

BACKGROUND

Questions remain about the shape of the dose-response relationship between body mass index (BMI) and pancreatic cancer risk, possible confounding by smoking, and differences by gender or geographic location. Whether abdominal obesity increases risk is unclear.

METHODS

We conducted a systematic review and meta-analysis of prospective studies of the association between BMI, abdominal fatness and pancreatic cancer risk and searched PubMed and several other databases up to January 2011. Summary relative risks (RRs) were calculated using a random-effects model.

RESULTS

Twenty-three prospective studies of BMI and pancreatic cancer risk with 9504 cases were included. The summary RR for a 5-unit increment was 1.10 [95% confidence interval (CI) 1.07-1.14, I(2) = 19%] and results were similar when stratified by gender and geographic location. There was evidence of a non-linear association, P(non-linearity) = 0.005; however, among nonsmokers, there was increased risk even within the 'normal' BMI range. The summary RR for a 10-cm increase in waist circumference was 1.11 (95% CI 1.05-1.18, I(2) = 0%) and for a 0.1-unit increment in waist-to-hip ratio was 1.19 (95% CI 1.09-1.31, I(2) = 11%).

CONCLUSIONS

Both general and abdominal fatness increases pancreatic cancer risk. Among nonsmokers, risk increases even among persons within the normal BMI range.

The complexities of obesity and diabetes with the development and progression of pancreatic cancer

Pancreatic cancer (PC) is one of the most lethal malignant diseases with the worst prognosis. It is ranked as the fourth leading cause of cancer-related deaths in the United States. Many risk factors have been associated with PC. Interestingly, large numbers of epidemiological studies suggest that obesity and diabetes, especially type-2 diabetes, are positively associated with increased risk of PC. Similarly, these chronic diseases (obesity, diabetes, and cancer) are also a major public health concern. In the U.S. population, 50 percent are overweight, 30 percent are medically obese, and 10 percent have diabetes mellitus (DM). Therefore, obesity and DM have been considered as potential risk factors for cancers; however, the focus of this article is restricted to PC. Although the mechanisms responsible for the development of these chronic diseases leading to the development of PC are not fully understood, the biological importance of the activation of insulin, insulin like growth factor-1 (IGF-1) and its receptor (IGF-1R) signaling pathways in insulin resistance mechanism and subsequent induction of compensatory hyperinsulinemia has been proposed. Therefore, targeting insulin/IGF-1 signaling with anti-diabetic drugs for lowering blood insulin levels and reversal of insulin resistance could be useful strategy for the prevention and/or treatment of PC. A large number of studies have demonstrated that the administration of anti-diabetic drugs such as metformin and thiazolidinediones (TZD) class of PPAR-γ agonists decreases the risk of cancers, suggesting that these agents might be useful anti-tumor agents for the treatment of PC. In this review article, we will discuss the potential roles of metformin and TZD anti-diabetic drugs as anti-tumor agents in the context of PC and will further discuss the complexities and the possible roles of microRNAs (miRNAs) in the pathogenesis of obesity, diabetes, and PC.

Can physical activity modulate pancreatic cancer risk? a systematic review and meta-analysis

Numerous epidemiological studies have examined the association between physical activity and pancreatic cancer; however, findings from individual cohorts have largely not corroborated a protective effect. Among other plausible mechanisms, physical activity may reduce abdominal fat depots inducing metabolic improvements in glucose tolerance and insulin sensitivity, thereby potentially attenuating pancreatic cancer risk. We performed a systematic review to examine associations between physical activity and pancreatic cancer. Six electronic databases were searched from their inception through July 2009, including MEDLINE and EMBASE, seeking observational studies examining any physical activity measure with pancreatic cancer incidence/mortality as an outcome. A random effects model was used to pool individual effect estimates evaluating highest vs. lowest categories of activity. Twenty-eight studies were included. Pooled estimates indicated a reduction in pancreatic cancer risk with higher levels of total (five prospective studies, RR: 0.72, 95% CI: 0.52-0.99) and occupational activity (four prospective studies, RR: 0.75, 95% CI: 0.59-0.96). Nonsignificant inverse associations were seen between risks and recreational and transport physical activity. When examining exercise intensity, moderate activity appeared more protective (RR: 0.79, 95% CI: 0.52-1.20) than vigorous activity (RR: 0.97, 95% CI: 0.85-1.11), but results were not statistically significant and the former activity variable incorporated marked heterogeneity. Despite indications of an inverse relationship with higher levels of work and total activity, there was little evidence of such associations with recreational and other activity exposures.

Body mass index, effect modifiers, and risk of pancreatic cancer: a pooled study of seven prospective cohorts

OBJECTIVE

To investigate whether the positive association of body mass index (BMI, kg/m(2)) with risk of pancreatic cancer is modified by age, sex, smoking status, physical activity, and history of diabetes.

METHODS

In a pooled analysis of primary data of seven prospective cohorts including 458,070 men and 485,689 women, we identified 2,454 patients with incident pancreatic cancer during an average 6.9 years of follow-up. Cox proportional hazard regression models were used in data analysis.

RESULTS

In a random-effects meta-analysis, for every 5 kg/m(2) increment in BMI, the summary relative risk (RR) was 1.06 (95% confidence interval (CI) 0.99-1.13) for men and 1.12 (95% CI 1.05-1.19) for women. The aggregate analysis showed that compared with normal weight (BMI: 18.5 to <25), the adjusted RR was 1.13 (95% CI 1.03-1.23) for overweight (BMI: 25 to <30) and 1.19 (95% CI 1.05-1.35) for obesity class I (BMI: 30 to <35). Tests of interactions of BMI effects by other risk factors were not statistically significant. Every 5 kg/m(2) increment in BMI was associated with an increased risk of pancreatic cancer among never and former smokers, but not among current smokers (P-interaction = 0.08).

CONCLUSION

The present evidence suggests that a high BMI is an independent risk factor of pancreatic cancer.

[Risk factors and early diagnosis of pancreatic cancer]

Pancreatic cancer (PC) is usually incurable. Identifying people at risk for developing PC may improve the prognosis of this entity. The main risk factors for PC are Peutz-Jeghers syndrome, hereditary pancreatitis and a history family of PC. Other factors, such as advanced age and smoking, should also be taken into account. PC screening is only useful in very high risk individuals. Tools that allow tumors to be identified in the early stages are required in order to apply appropriate curative treatments. In this scenario, only endoscopic ultrasound with cytological analysis of suspicious pancreatic lesions has proved to be useful.

Inflammation and pancreatic cancer: an evidence-based review

There is a growing awareness that inflammation plays a contributory role in numerous pathologies, including pancreatic carcinogenesis. Inflammatory states are characterized by the creation of reactive oxygen species and the induction of cell cycling for tissue growth and repair. The initiation, promotion and expansion of tumors may be influenced by numerous components that function in the inflammatory response. Recognized risk factors for pancreatic cancer include cigarette smoking, chronic/hereditary pancreatitis, obesity and type II diabetes. Each risk factor is linked by the fact that the inflammatory state significantly drives its pathology. This article will outline how inflammatory mechanisms are etiologically linked to pancreatic adenocarcinoma.

Epidemiological and molecular mechanisms aspects linking obesity and cancer

About 25% of cancer cases globally are due to excess weight and a sedentary lifestyle. These results are alarming, as the world knows a pandemic of obesity and, in consequence, insulin resistance. Obesity may increase risk for various cancers by several mechanisms, including increasing sex and metabolic hormones, and inflammation. Here, we present a review of epidemiological and molecular evidences linking obesity and cancer--particularly colorectal, post-menopausal breast, endometrial, pancreatic, high grade prostate, hepatocellular, gallbladder, kidney and esophageal adenocarcinoma. The expected striking increase in the incidence of cancer in the near future related to obesity turns the knowledge of this field of great impact as it is needed to the development of strategies to prevent and treat this disease.