Association of obesity with DNA mismatch repair status and clinical outcome in patients with stage II or III colon carcinoma participating in NCCTG and NSABP adjuvant chemotherapy trials

Post-diagnosis adiposity and colorectal cancer prognosis: A Global Cancer Update Programme (CUP Global) systematic literature review and meta-analysis

The adiposity influence on colorectal cancer prognosis remains poorly characterised. We performed a systematic review and meta-analysis on post-diagnosis adiposity measures (body mass index [BMI], waist circumference, waist-to-hip ratio, weight) or their changes and colorectal cancer outcomes. PubMed and Embase were searched through 28 February 2022. Random-effects meta-analyses were conducted when at least three studies had sufficient information. The quality of evidence was interpreted and graded by the Global Cancer Update Programme (CUP Global) independent Expert Committee on Cancer Survivorship and Expert Panel. We reviewed 124 observational studies (85 publications). Meta-analyses were possible for BMI and all-cause mortality, colorectal cancer-specific mortality, and cancer recurrence/disease-free survival. Non-linear meta-analysis indicated a reverse J-shaped association between BMI and colorectal cancer outcomes (nadir at BMI 28 kg/m2). The highest risk, relative to the nadir, was observed at both ends of the BMI distribution (18 and 38 kg/m2), namely 60% and 23% higher risk for all-cause mortality; 95% and 26% for colorectal cancer-specific mortality; and 37% and 24% for cancer recurrence/disease-free survival, respectively. The higher risk with low BMI was attenuated in secondary analyses of RCTs (compared to cohort studies), among studies with longer follow-up, and in women suggesting potential methodological limitations and/or altered physiological state. Descriptively synthesised studies on other adiposity-outcome associations of interest were limited in number and methodological quality. All the associations were graded as limited (likelihood of causality: no conclusion) due to potential methodological limitations (reverse causation, confounding, selection bias). Additional well-designed observational studies and interventional trials are needed to provide further clarification.

Potential roles of sex-linked differences in obesity and cancer immunotherapy: revisiting the obesity paradox

Obesity, a condition of excess adiposity usually defined by a BMI > 30, can have profound effects on both metabolism and immunity, connecting the condition with a broad range of diseases, including cancer and negative outcomes. Obesity and cancer have been associated with increased incidence, progression, and poorer outcomes of multiple cancer types in part due to the pro-inflammatory state that arises. Surprisingly, obesity has also recently been demonstrated in both preclinical models and clinical outcomes to be associated with improved response to immune checkpoint inhibition (ICI). These observations have laid the foundation for what has been termed the "obesity paradox". The mechanisms underlying these augmented immunotherapy responses are still unclear given the pleiotropic effects obesity exerts on cells and tissues. Other important variables such as age and sex are being examined as further affecting the obesity effect. Sex-linked factors exert significant influences on obesity biology, metabolism as well as differential effects of different immune cell-types. Age can be another confounding factor contributing to the effects on both sex-linked changes, immune status, and obesity. This review aims to revisit the current body of literature describing the immune and metabolic changes mediated by obesity, the role of obesity on cancer immunotherapy, and to highlight questions on how sex-linked differences may influence obesity and immunotherapy outcome.

Multiomics Analysis Reveals Cuproptosis-Related Signature for Evaluating Prognosis and Immunotherapy Efficacy in Colorectal Cancer

Cuproptosis is a copper-induced form of mitochondrial cell death which is engaged in the proliferation and migration of a variety of tumors. Nevertheless, the role of cuproptosis in tumor microenvironment (TME) remodeling and antitumor therapy is still poorly understood. We characterized two diverse cuproptosis-associated molecular isoforms in CRC which exhibit distinct prognostic and TME characteristics. Subsequently, we constructed a cuproptosis-associated prognostic model containing five genes and divided the patients into a high CPS-score group and a low CPS-score group. Univariate and multivariate Cox analyses showed that the CPS score could be used as an independent prognostic factor. The nomogram, and its consequent calibration curves, indicated that this prognostic signature had good predictive power for CRC. The analysis of single-cell sequencing data showed the significant expression of HES4 and SPHK1 in various immune and stromal (including fibroblasts) cells. Further studies showed that tumor mutational burden (TMB), high microsatellite instability (MSI-H) ratio, immune checkpoint blockade (ICB), and human leukocyte antigen (HLA) gene expression all positively correlated with the CPS score, predicting a better reaction to immunotherapy in high CPS-core patients. The CPS score constructed from cuproptosis subtypes can be used as a predictive tool to evaluate the prognosis of CRC patients and their response to immunotherapy.

Race, age, and sex differences on the influence of obesity on colorectal cancer sidedness and mortality: A national cross‐sectional study

BACKGROUND AND OBJECTIVES

Colorectal cancer (CRC) sidedness is recognized as a prognostic factor for survival; left-sided colorectal cancer is associated with better outcomes than right-sided colon cancer (RsCC). We aimed to evaluate the influence of obesity on CRC sidedness and determine how race, age, and sex affect mortality among overweight and obese individuals.

METHODS

A survey-weighted analysis was conducted using data obtained from the National Inpatient Sample between 2016 and 2019.

RESULTS

Of the 24 549 patients with a diagnosis of CRC and a reported body mass index (BMI), 13.6% were overweight and 49.9% were obese. The race distribution was predominantly non-Hispanic Whites (69.7%), followed by Black (15.6%), Hispanic (8.7%), and other race (6.1%). Overweight (BMI: 25-29.9) and obese (BMI: ≥30) individuals were more likely to have RsCC (adjusted OR [aOR] = 1.28; 95% CI: 1.17-1.39, p < 0.001 and aOR = 1.45; 95% CI: 1.37-1.54, p < 0.001, respectively). Obese Black individuals were more likely to have RsCC as compared to their White counterparts (aOR = 1.23; 95% CI: 1.09-1.38).

CONCLUSIONS

Obesity is associated with an increased risk of RsCC. In addition, racial disparities in CRC sidedness and outcomes are most pronounced among obese patients.

Nutritional Factors during and after Cancer: Impacts on Survival and Quality of Life

The French National Cancer Institute conducted a collective expertise study with researchers and clinical experts from the French Network for Nutrition And Cancer Research (NACRe Network). The objective was to update the state of knowledge on the impacts of nutritional factors on clinical endpoints during or after cancer. Data from 150 meta-analyses, pooled analyses or intervention trials and 93 cohort studies were examined; they concerned 8 nutritional factors, 6 clinical events and 20 cancer locations. This report shows that some nutritional factors have impacts on mortality and on the risks of recurrence or second primary cancer in cancer patients. Therefore, high-risk nutritional conditions can be encountered for certain cancer sites: from the diagnosis and throughout the health care pathways, weight loss (lung and esophageal cancers), malnutrition (lung, esophageal, colorectal, pancreatic, gastric and liver cancers), weight gain (colorectal, breast and kidney cancers) and alcohol consumption (upper aerodigestive cancers) should be monitored; and after cancer treatments, excess weight should be detected (colorectal, breast and kidney cancers). These situations require nutritional assessments, and even support or management by health care professionals, in the context of tertiary prevention. This report also highlights some limitations regarding the existing literature and some needs for future research.

[Impact of nutritional factors during and after cancer]

Nutritional factors (diet, weight, alcohol, physical activity) are identified as factors having an impact on the onset of several cancer sites. Less abundant scientific data also underline their impact on the tumor progression. A review of the scientific literature was carried out by a group of experts established by the French National Cancer Institute (INCa) to better document the influence of nutritional factors during and after cancer on outcomes such as overall mortality, cancer specific mortality, recurrence, second primary cancers and quality of life. This analysis of the literature completes messages of reduction of alcohol consumption, prevention of undernutrition or excess weight and adherence to dietary recommendations, avoiding the use of dietary supplements, fasting or restrictive diets and strengthens messages promoting the practice of physical activity and the fight against sedentary lifestyle.

Association of Obesity With Survival Outcomes in Patients With Cancer: A Systematic Review and Meta-analysis

Importance

Obesity, defined as a body mass index (BMI) greater than 30, is associated with a significant increase in the risk of many cancers and in overall mortality. However, various studies have suggested that patients with cancer and no obesity (ie, BMI 20-25) have worse outcomes than patients with obesity.

Objective

To assess the association between obesity and outcomes after a diagnosis of cancer.

Data Sources

PubMed, the Cochrane Library, and EMBASE were searched from inception to January 2020.

Study Selection

Studies reporting prognosis of patients with obesity using standard BMI categories and cancer were included. Studies that used nonstandard BMI categories, that were limited to children, or that were limited to patients with hematological malignant neoplasms were excluded. Screening was performed independently by multiple reviewers. Among 1892 retrieved studies, 203 (17%) met inclusion criteria for initial evaluation.

Data Extraction and Synthesis

The Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines were reporting guideline was followed. Data were extracted by multiple independent reviewers. Risk of death, cancer-specific mortality, and recurrence were pooled to provide an adjusted hazard ratio (HR) with a 95% CI . A random-effects model was used for the retrospective nature of studies.

Main Outcomes and Measures

The primary outcome of the study was overall survival (OS) in patients with cancer, with and without obesity. Secondary end points were cancer-specific survival (CSS) and progression-free survival (PFS) or disease-free survival (DFS). The risk of events was reported as HRs with 95% CIs, with an HR greater than 1 associated with a worse outcome among patients with obesity vs those without.

Results

A total of 203 studies with 6 320 365 participants evaluated the association of OS, CSS, and/or PFS or DFS with obesity in patients with cancer. Overall, obesity was associated with a reduced OS (HR, 1.14; 95% CI, 1.09-1.19; P < .001) and CSS (HR, 1.17; 95% CI, 1.12-1.23; P < .001). Patients were also at increased risk of recurrence (HR, 1.13; 95% CI, 1.07-1.19; P < .001). Conversely, patients with obesity and lung cancer, renal cell carcinoma, or melanoma had better survival outcomes compared with patients without obesity and the same cancer (lung: HR, 0.86; 95% CI, 0.76-0.98; P = .02; renal cell: HR, 0.74; 95% CI, 0.53-0.89; P = .02; melanoma: HR, 0.74; 95% CI, 0.57-0.96; P < .001).

Conclusions and Relevance

In this study, obesity was associated with greater mortality overall in patients with cancer. However, patients with obesity and lung cancer, renal cell carcinoma, and melanoma had a lower risk of death than patients with the same cancers without obesity. Weight-reducing strategies may represent effective measures for reducing mortality in these patients.

Differences in the molecular profile of endometrial cancers from British White and British South Asian women

Objectives

To identify differences in the mutational profile of endometrial tumours between British White (BW) and South Asian (BSA) women.

Methods

We analysed primary tumours from matched cohorts of British White (BW) and British South Asian (BSA) women resident in Leicestershire diagnosed with EC. Next Generation Sequencing was performed to investigate mutational differences in a panel of 10 genes previously identified as being commonly mutated in EC. The presence of somatic Mismatch Repair (MMR) gene deficiencies was determined by immunohistochemistry.

Results

In total, 57 tumours (27 BSA and 30 BW) were sequenced. There was no significant difference in the overall mutation frequency of the 10 genes analysed; however, numerous differences were observed between the groups. There was a positive association between PIK3CA and PTEN mutations in the BSA group, with 78% of PIK3CA-mutant tumours harbouring a PTEN mutation, whereas only 11% of PIK3CA wild-type (wt) tumours were PTEN mutant positive (p = 0.0012). In BW women, 90% of ARID1A mutant tumours had co-existent PI3K pathway mutations versus 50% of wild-type (wt) ARID1A patients (p = 0.0485). This trend was not significant in the BSA group (p = 0.66). The age at diagnosis was significantly higher in the BW group with a somatic MMR gene deficiency compared to those with no deficiency (72.8 years versus 59.6 years, p = 0.007), whereas this difference was not seen in the BSA group (64 years versus 60 years, p = 0.37).

Conclusion

We have identified differences in the mutational profile of primary EC tumours from BW and BSA women. Further research is needed to confirm these findings and to explore their potential implications for early detection, treatment response and prognosis.

Microsatellite Instability and Life Style Factors in Sporadic Colorectal Cancer

Background:

Colorectal cancer (CRC) in Egypt is a relatively high young onset disease. As a form of heterogeneous cancer, there is interplay between genetic and environmental factors. We aimed at probing the association of life style factors and Microsatellite Instability (MSI) status that could provide more insights on carcinogenic process of CRC.

Methods:

One hundred incident sporadic CRC patients were involved. Information on risk factors of CRC was obtained and microsatellite instability status was predicted through evaluation of MMR protein expression via immunohistochemistry (IHC).

Results:

Median age was 47.50 years, females represented 54.0% and 36% of patients were Microsatellite Instability High (MSI-H). Most patients with right sided colon cancer (78.3%) were MSI-H while mostly stable or low MSS/MSI-L for left-sided colon and rectum (78.6%, 74.3% respectively, p<0.001). Patients with low physical activity had higher risk of MSS/MSI-L than those with moderate or high activity p =0.026. Patients with BMI greater than 30 Kg/m² had higher MSS/MSI-L (75.5%) than those with BMI between 25-30 Kg/m² (60.6%) and those with normal BMI <25 (38.9%), p for trend = 0.006. On subgroup analyses, the association of high BMI with MSS/MSI-L was only shown in patients younger than 40 years, females, stage III, non-mucin secreting adenocarcinoma and a significant interaction with physical activity.

Conclusion:

In Conclusion, the present study confirms the increased risk of MSS/MSI-L with increased BMI and speculates this association to be modified by patient’s life style and tumor characteristics. Further research is needed to validate present results.

Obesity and cancer: A mechanistic overview of metabolic changes in obesity that impact genetic instability

Obesity, defined as a state of positive energy balance with a body mass index exceeding 30 kg/m2 in adults and 95th percentile in children, is an increasing global concern. Approximately one-third of the world's population is overweight or obese, and in the United States alone, obesity affects one in six children. Meta-analysis studies suggest that obesity increases the likelihood of developing several types of cancer, and with poorer outcomes, especially in children. The contribution of obesity to cancer risk requires a better understanding of the association between obesity-induced metabolic changes and its impact on genomic instability, which is a major driving force of tumorigenesis. In this review, we discuss how molecular changes during adipose tissue dysregulation can result in oxidative stress and subsequent DNA damage. This represents one of the many critical steps connecting obesity and cancer since oxidative DNA lesions can result in cancer-associated genetic instability. In addition, the by-products of the oxidative degradation of lipids (e.g., malondialdehyde, 4-hydroxynonenal, and acrolein), and gut microbiota-mediated secondary bile acid metabolites (e.g., deoxycholic acid and lithocholic acid), can function as genotoxic agents and tumor promoters. We also discuss how obesity can impact DNA repair efficiency, potentially contributing to cancer initiation and progression. Finally, we outline obesity-related epigenetic changes and identify the gaps in knowledge to be addressed for the development of better therapeutic strategies for the prevention and treatment of obesity-related cancers.

[Obesity and Cancer]

In the past decades, obesity and overweight prevalence has been rising worldwide, in both men and women. In France, the prevalence of overweight in adults was 49% in 2015 (54% among men and 44% among women), including 17% of obese adults. According to the last evaluation performed by IARC in 2017, overweight and obesity are established risk factors for 13 cancer sites with risk estimates per 5kg/m2 varying largely depending on the cancer site. In 2015 in France, 5.4% of cancer cases could be attributed to excess weight, corresponding to 18,600 cases, including 3400 colon cancers, 2600 kidney cancers, 4500 breast cancers and 2500 endometrial cancers. Obesity is also related to worse prognosis for some cancers, in particular breast and colon cancers. Obesity in children and adolescents, also rising in many countries, has also been associated to an increase in adult cancer risk. A major cause of obesity is a disequilibrium in energy balance favoured by a diet rich in processed food, red meat, trans and saturated fatty acids, sweetened foods and beverages and poor in fruits and vegetables, legumes and whole grains. Main national and international recommendations to reduce the prevalence of obesity are to have a balanced diet and regular physical activity.

Gut microbiome meta-analysis reveals dysbiosis is independent of body mass index in predicting risk of obesity-associated CRC

Objective

Obesity is a risk factor for colorectal cancer (CRC), accounting for more than 14% of CRC incidence. Microbial dysbiosis and chronic inflammation are common characteristics in both obesity and CRC. Human and murine studies, together, demonstrate the significant impact of the microbiome in governing energy metabolism and CRC development; yet, little is understood about the contribution of the microbiome to development of obesity-associated CRC as compared to individuals who are not obese.

Design

In this study, we conducted a meta-analysis using five publicly available stool and tissue-based 16S rRNA and whole genome sequencing (WGS) data sets of CRC microbiome studies. High-resolution analysis was employed for 16S rRNA data, which allowed us to achieve species-level information to compare with WGS.

Results

Characterisation of the confounders between studies, 16S rRNA variable region and sequencing method did not reveal any significant effect on alpha diversity in CRC prediction. Both 16S rRNA and WGS were equally variable in their ability to predict CRC. Results from diversity analysis confirmed lower diversity in obese individuals without CRC; however, no universal differences were found in diversity between obese and non-obese individuals with CRC. When examining taxonomic differences, the probability of being classified as CRC did not change significantly in obese individuals for all taxa tested. However, random forest classification was able to distinguish CRC and non-CRC stool when body mass index was added to the model.

Conclusion

Overall, microbial dysbiosis was not a significant factor in explaining the higher risk of colon cancer among individuals with obesity.

Comparison of microsatellite status detection methods in colorectal carcinoma

There are two commonly accepted methods for detecting microsatellite status. One is to detect amplified microsatellite loci by polymerase chain reaction (PCR) and the other is to detect mismatch repair gene (MMR) protein expression by immunohistochemistry (IHC). PCR detection is considered to be accurate in clinical operations while IHC is widely used due to ease of operation and lesser expense. In order to compare IHC with PCR in detecting microsatellite status in colorectal carcinoma, a total of 569 samples of colorectal carcinoma resection were collected in the Department of Pathology, Nanjing Drum Tower Hospital, between June 2014 and June 2017. In all samples, IHC and PCR was used to detect microsatellite status and the consistency of results between the two methods was compared. We found that 48 cases of microsatellite instability (MSI) were detected by PCR including 37 cases of microsatellite instability high (MSI-H), 11 cases of microsatellite instability low (MSI-L), and 521 cases of MSS. MSI accounted for 8.44% of all cases and MSI-H accounted for 6.50%. IHC results of the 569 patients showed that 69 cases were deficient mismatch repair (dMMR) and 500 cases were proficient mismatch repair (pMMR). dMMR accounted for 12.13% of all cases. Loss expression of PMS2 protein was the most common while MSH6 was rare. The coincidence rate of the two methods for detecting microsatellite states was 91.92%. IHC and the PCR method had high consistency in microsatellite status. Compared with PCR, the IHC method is more economical and more convenient for clinical operations. When the 4 repair proteins were without deficiency detected by IHC, it could be diagnosed as MSS/MSI-L and further PCR was not necessary. When any repair protein was found to be deficient, PCR detection was needed to determine whether MSI existed. Our conclusion will save a lot of time and costs in clinical work.

Deficient mismatch repair and RAS mutation in colorectal carcinoma patients: a retrospective study in Eastern China

Objectives

To investigate the frequency and prognostic role of deficient mismatch repair (dMMR) and RAS mutation in Chinese patients with colorectal carcinoma.

Methods

Clinical and pathological information from 813 patients were reviewed and recorded. Expression of mismatch repair proteins was tested by immunohistochemistry. Mutation analyses for RAS gene were performed by real-time polymerase chain reaction. Correlations of mismatch repair status and RAS mutation status with clinicopathological characteristics and disease survival were determined.

Results

The overall percentage of dMMR was 15.18% (121/797). The proportion of dMMR was higher in patients <50 years old (p < 0.001) and in the right side of the colon (p < 0.001). Deficient mismatch repair was also associated with mucinous production (p < 0.001), poor differentiation (p < 0.001), early tumor stage (p < 0.05) and bowel wall invasion (p < 0.05). The overall RAS mutation rate was 45.88%, including 42.56% (346/813) KRAS mutation and 3.69% (30/813) NRAS mutation (including three patients with mutations in both). KRAS mutation was significantly associated with mucinous production (p < 0.05), tumor stage (p < 0.05) and was higher in non-smokers (p < 0.05) and patients with a family history of colorectal carcinoma (p < 0.05). Overall, 44.63% (54/121) dMMR tumors harbored KRAS mutation, however, dMMR tumors were less likely to have NRAS mutation. Moreover, dMMR, KRAS and NRAS mutation were not prognostic factors for stage I–III colorectal carcinoma.

Conclusions

This study confirms that the status of molecular markers involving mismatch repair status and RAS mutation reflects the specific clinicopathological characteristics of colorectal carcinoma.

A network-based predictive gene-expression signature for adjuvant chemotherapy benefit in stage II colorectal cancer

Background

The clinical benefit of adjuvant chemotherapy for stage II colorectal cancer (CRC) is controversial. This study aimed to explore novel gene signature to predict outcome benefit of postoperative 5-Fu-based therapy in stage II CRC.

Methods

Gene-expression profiles of stage II CRCs from two datasets with 5-Fu-based adjuvant chemotherapy (training dataset, n = 212; validation dataset, n = 85) were analyzed to identify the indicator. A systemic approach by integrating gene-expression and protein-protein interaction (PPI) network was implemented to develop the predictive signature. Kaplan-Meier curves and Cox proportional hazards model were used to determine the survival benefit of adjuvant chemotherapy. Experiments with shRNA knock-down were carried out to confirm the signature identified in this study.

Results

In the training dataset, we identified 44 PPI sub-modules, by which we separate patients into two clusters (1 and 2) having different chemotherapeutic benefit. A predictor of 11 PPI sub-modules (11-PPI-Mod) was established to discriminate the two sub-groups, with an overall accuracy of 90.1%. This signature was independently validated in an external validation dataset. Kaplan-Meier curves showed an improved outcome for patients who received adjuvant chemotherapy in Cluster 1 sub-group, but even worse survival for those in Cluster 2 sub-group. Similar results were found in both the training and the validation dataset. Multivariate Cox regression revealed an interaction effect between 11-PPI-Mod signature and adjuvant therapy treatment in the training dataset (RFS, p = 0.007; OS, p = 0.006) and the validation dataset (RFS, p = 0.002). From the signature, we found that PTGES gene was up-regulated in CRC cells which were more resistant to 5-Fu. Knock-down of PTGES indicated a growth inhibition and up-regulation of apoptotic markers induced by 5-Fu in CRC cells.

Conclusions

Only a small proportion of stage II CRC patients could benefit from adjuvant therapy. The 11-PPI-Mod as a potential predictor could be helpful to distinguish this sub-group with favorable outcome.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3821-4) contains supplementary material, which is available to authorized users.

The Impact of Microsatellite Instability Status and Sidedness of the Primary Tumor on the Effect of Cetuximab-Containing Chemotherapy in Patients with Metastatic Colorectal Cancer

Background: Colorectal cancer (CRC) has been reconsidered as a heterogeneous disease. Among advances of genomic analysis in CRC, the sidedness of tumors (left-sided colon vs. right-sided colon) and microsatellite instability (MSI)-high (H) tumors have been highlighted.

Methods: We analyzed 153 CRC patients who were available for evaluation of MSI status and had been treated with cetuximab-containing chemotherapy between April 2008 and January 2013. KRAS mutational status was available in all 153 patients, but BRAF mutational status was only available in 72 patients (47.1%). We evaluated the impact of microsatellite instability status and location of the primary colon tumor on the effect of cetuximab-containing chemotherapy in patients with metastatic colorectal cancer.

Results: MSI-H was detected in 3.9% of analyzed patients. Characteristics of patients, with the exception of BRAF mutational status, were generally similar between those with right and left-sided tumors. Right-sided tumors were significantly associated with a BRAF mutation (p=0.023). In addition, patient characteristics with an MSS tumor were not different from those with an MSI-H tumor. For all 153 patients, the most commonly used regimen that included cetuximab was irinotecan alone, irrespective of treatment line. There was no significant difference in treatment efficacy in either RR or disease control rate (DCR) between the MSI-H and MSS groups. There was also no difference in RR and DCR according to the location of the primary tumor (left side vs. right side). No significant difference in PFS was observed between the MSI-H and MSS groups (4.80 months vs. 5.80 months; p=0.238) or the left-side and right-side groups (6.10 months vs. 4.20 months; p=0.278). In a subgroup-analysis of 140 patients with wild-type KRAS, there was no difference in PFS following cetuximab-containing therapy based on MSI status or the location of the primary tumor.

Conclusions: MSI status and the location of the primary tumor were not novel biomarkers for response to cetuximab-containing therapy in metastatic CRC. Further prospective validation of the prognostic or predictive capacity of MSI status and the sidedness of tumors is warranted.

Oncologic and Functional Hazards of Obesity Among Patients With Locally Advanced Rectal Cancer Following Neoadjuvant Chemoradiation Therapy

OBJECTIVE

Obesity is a major health concern and risk factor for colorectal cancer that may also impact cancer treatment and outcomes. Rectal cancer response to chemoradiotherapy (CXRT) is associated with long-term survival and sphincter preservation. The purpose of this study was to evaluate the impact of obesity on treatment outcomes after neoadjuvant CXRT for rectal cancer.

METHODS

A retrospective cohort study of patients diagnosed (1993 to 2010) with cT3-4 or cN+ (by endorectal ultrasound, computed tomography, or magnetic resonance imaging) rectal carcinoma and treated with CXRT and total mesorectal excision was performed. Patients were classified as obese (body mass index ≥30 kg/m) or nonobese (body mass index <30 kg/m), and by response to CXRT: complete (pCR) or incomplete (pIR). Associations between obesity, tumor response, and sphincter preservation were evaluated using multivariate logistic regression analysis and survival outcomes by Cox regression.

RESULTS

A total of 753 patients met criteria and 28.7% (n=216) patients were obese. Obese and nonobese groups did not differ in age, sex, tumor location, grade, or number of examined lymph nodes. However, obesity was associated with a lower rate of pCR (ORmulti=0.60; 95% confidence interval, 0.38-0.94; P=0.04) and among mid to low rectal cancer patients, a lower rate of sphincter preservation (ORmulti=0.67; 95% confidence interval, 0.45-0.99). Among both obese and nonobese patients, CR was associated with more favorable recurrence-free survival than pIR.

CONCLUSIONS

Considering the increasing obesity prevalence and its association with CXRT response, oncologic outcomes, and sphincter preservation, further study is needed regarding the impact of obesity on neoadjuvant treatment response. Moreover, obesity should be targeted as a modifiable risk factor for adverse outcomes following multimodality treatment for rectal cancer.

Vitamin E Modifies High-Fat Diet-Induced Increase of DNA Strand Breaks, and Changes in Expression and DNA Methylation of Dnmt1 and MLH1 in C57BL/6J Male Mice

Obesity is associated with low-grade inflammation, increased ROS production and DNA damage. Supplementation with antioxidants might ameliorate DNA damage and support epigenetic regulation of DNA repair. C57BL/6J male mice were fed a high-fat (HFD) or a control diet (CD) with and without vitamin E supplementation (4.5 mg/kg body weight (b.w.)) for four months. DNA damage, DNA promoter methylation and gene expression of Dnmt1 and a DNA repair gene (MLH1) were assayed in liver and colon. The HFD resulted in organ specific changes in DNA damage, the epigenetically important Dnmt1 gene, and the DNA repair gene MLH1. Vitamin E reduced DNA damage and showed organ-specific effects on MLH1 and Dnmt1 gene expression and methylation. These results suggest that interventions with antioxidants and epigenetic active food ingredients should be developed as an effective prevention for obesity—and oxidative stress—induced health risks.

Is obesity an advantage in patients with colorectal cancer?

Obesity/higher BMI appears to be important determinants in the development of colon cancer as well as in predicting outcomes in the adjuvant setting in these patients. These associations seem to be stronger for men and tend to be 'J-shaped', with worse outcomes in both lower and upper BMI categories than in the middle categories. How this factors in the metastatic setting is less clear. A recent pooled analysis of patients with metastatic colorectal cancer receiving bevacizumab in the first-line setting observed that patients with the lowest BMI had the lowest median overall survival. An incremental BMI increase of 5 kg/m(2) led to actually a decrease in the risk of death (hazard ratio, 0.911 [95% CI, 0.879-0.944]). The observed association does not necessarily mean that obesity is an advantage for patients with metastatic colorectal cancer. More likely, it is conceivable that, in patients with metastatic colorectal cancer with a lower BMI, the effects of cancer-related cachexia may be more deleterious than the potential adverse events related to a higher BMI. In patients already diagnosed with metastatic disease, studying how body weight affects tumor biology and treatment-related decisions are important considerations.

Prognostic Role of Body Mass Index in Advanced Small Bowel Adenocarcinoma Patients Receiving Palliative Chemotherapy

As small bowel adenocarcinoma (SBA) is a rare cancer worldwide, prognostic factors have not been clearly defined. The purpose of this study is to assess the prognostic role of clinicopathologic features, including body mass index (BMI), in patients with advanced SBA. A total of 28 consecutive patients with advanced SBA treated with palliative chemotherapy were retrospectively enrolled and analyzed. Clinicopathologic features, progression-free survival (PFS), and overall survival (OS) were compared according to BMI level. Eighteen patients had BMI < 25 kg/m(2) (overweight/normal/underweight in Asian) and ten patients had BMI ≥ 25 kg/m(2) (obese in Asian). Baseline characteristics were similar regardless of patient's BMI. Compared to patients with BMI < 25 kg/m(2), patients with BMI ≥ 25 kg/m(2) had higher response rate to chemotherapy (40.0% vs. 0%, P = 0.010), longer OS (11.2 vs. 7.0 months, P = 0.018) and a tendency toward prolonged PFS (2.1 vs. 1.9 months, P = 0.085). Multivariate analysis revealed that BMI ≥ 25 kg/m(2) is an independent positive prognostic factor of OS (adjusted hazard ratio 0.35, P = 0.024). In conclusion, baseline BMI ≥ 25 kg/m(2) has a positive prognostic role in patients with advanced SBA.

Immunohistochemical detection of the BRAF V600E mutant protein in colorectal neoplasms

Reliable assessment of the BRAF mutation status is becoming increasingly important in the clinical management of colorectal carcinomas (CRC). The aim of this study was to investigate the use of a recently developed mutation-specific antibody (VE1; SpringBio, Pleasanton, CA) to detect the BRAF V600E protein in paraffin tissue. We analyzed by immunohistochemistry (IHC) 117 cases that had been evaluated for BRAF mutation using a MALDI-TOF mass spectrometry-based assay. Immunohistochemical staining was evaluated without the knowledge of the genetic data and was considered positive when there was distinct homogenous cytoplasmic staining in the tumor cells. The analyzed cases included 4 polyps, 63 primary CRC, and 50 metastatic CRC. Forty-five of the 46 (97.8%) cases that were positive by IHC had a BRAF V600E mutation by genetic analysis; the 1 discordant case was notably of signet ring cell type. Similarly, 66 of the 67 (98.5%) cases that were negative by IHC were also negative by genetic analysis. Four cases that showed weak cytoplasmic staining and/or nuclear staining in the tumor cells were considered to be IHC equivocal; by genetic analysis, 2 of the 4 were positive and 2 were negative. The overall sensitivity and specificity of IHC for the detection of a BRAF V600E mutant tumor was 93.7% and 95.6%, respectively. Our results support the use of VE1 IHC for identification of colorectal neoplasms harboring the BRAF V600E mutation. Difficulties in immunohistochemical interpretation may arise in a small number of cases and in those cases molecular testing is required.

Personalized treatment for patients with colorectal cancer: role of biomarkers

The systemic treatment of patients with colorectal cancer (CRC) has traditionally been based on clinical and tumor histological criteria. Recently however, several prognostic and predictive biomarkers have been proposed for patients with newly diagnosed CRC, including the subgroup with stage II disease. Among the best validated prognostic biomarkers for CRC are CEA levels, MS instability status and certain gene signatures. Although no biomarker currently exists for identifying patients likely to benefit from chemotherapy, the mutational status of KRAS and NRAS is used to predict response to cetuximab and panitumumab. For upfront identification of patients at high risk of suffering from severe therapy-related toxicity, specific variants of dihydropyrimidine dehydrogenase may be measured for predicting toxicity from fluoropyrimidines and uridine diphosphate glucuronosyltransferase*28 (UGT1A1*28) for predicting toxicity from irinotecan.

Surveillance and Survivorship after Treatment for Colon Cancer

Colorectal cancer is the third most common cancer diagnosed in the United States. Majority of patients have localized disease that is amenable to curative resection. Disease recurrence remains a major concern after resection. In addition, patients are at an increased risk for developing a second or metachronous colon cancer. The principal goal of surveillance following treatment of colon cancer is to improve disease-free and overall survival. Survivorship is a distinct phase following surveillance to help improve quality of life and promote longevity.

Obesity, Aspirin, and Risk of Colorectal Cancer in Carriers of Hereditary Colorectal Cancer: A Prospective Investigation in the CAPP2 Study

PURPOSE

In the general population, increased adiposity is a significant risk factor for colorectal cancer (CRC), but whether obesity has similar effects in those with hereditary CRC is uncertain. This prospective study investigated the association between body mass index and cancer risk in patients with Lynch syndrome (LS).

PATIENTS AND METHODS

Participants with LS were recruited to the CAPP2 study, in which they were randomly assigned to receive aspirin 600 mg per day or aspirin placebo, plus resistant starch 30 g per day or starch placebo (2 × 2 factorial design). Mean intervention period was 25.0 months, and mean follow-up was 55.7 months.

RESULTS

During follow-up, 55 of 937 participants developed CRC. For obese participants, CRC risk was 2.41× (95% CI, 1.22 to 4.85) greater than for underweight and normal-weight participants (reference group), and CRC risk increased by 7% for each 1-kg/m(2) increase in body mass index. The risk of all LS-related cancers in obese people was 1.77× (95% CI, 1.06 to 2.96; P = .03) greater than for the reference group. In subgroup analysis, obesity was associated with 3.72× (95% CI, 1.41 to 9.81) greater CRC risk in patients with LS with MLH1 mutation, but no excess risk was observed in those with MSH2 or MSH6 mutation (P = .5). The obesity-related excess CRC risk was confined to those randomly assigned to the aspirin placebo group (adjusted hazard ratio, 2.75; 95% CI, 1.12 to 6.79; P = .03).

CONCLUSION

Obesity is associated with substantially increased CRC risk in patients with LS, but this risk is abrogated in those taking aspirin. Such patients are likely to benefit from obesity prevention and/or regular aspirin.

Survivorship: nutrition and weight management, Version 2.2014. Clinical practice guidelines in oncology

Healthy lifestyle habits have been associated with improved health outcomes and quality of life and, for some cancers, a reduced risk of recurrence and death. The NCCN Guidelines for Survivorship therefore recommend that cancer survivors be encouraged to achieve and maintain a healthy lifestyle, including attention to weight management, physical activity, and dietary habits. This section of the NCCN Guidelines focuses on recommendations regarding nutrition, weight management, and supplement use in survivors. Weight management recommendations are based on the survivor's body mass index and include discussions of nutritional, weight management, and physical activity principles, with referral to community resources, dietitians, and/or weight management programs as needed.

Association between body mass index and mortality for colorectal cancer survivors: overall and by tumor molecular phenotype

BACKGROUND

Microsatellite instability (MSI) and BRAF mutation status are associated with colorectal cancer survival, whereas the role of body mass index (BMI) is less clear. We evaluated the association between BMI and colorectal cancer survival, overall and by strata of MSI, BRAF mutation, sex, and other factors.

METHODS

This study included 5,615 men and women diagnosed with invasive colorectal cancer who were followed for mortality (maximum: 14.7 years; mean: 5.9 years). Prediagnosis BMI was derived from self-reported weight approximately one year before diagnosis and height. Tumor MSI and BRAF mutation status were available for 4,131 and 4,414 persons, respectively. Multivariable hazard ratios (HR) and 95% confidence intervals (CI) were estimated from delayed-entry Cox proportional hazards models.

RESULTS

In multivariable models, high prediagnosis BMI was associated with higher risk of all-cause mortality in both sexes (per 5-kg/m(2); HR, 1.10; 95% CI, 1.06-1.15), with similar associations stratified by sex (Pinteraction: 0.41), colon versus rectum (Pinteraction: 0.86), MSI status (Pinteraction: 0.84), and BRAF mutation status (Pinteraction: 0.28). In joint models, with MS-stable/MSI-low and normal BMI as the reference group, risk of death was higher for MS-stable/MSI-low and obese BMI (HR, 1.32; P value: 0.0002), not statistically significantly lower for MSI-high and normal BMI (HR, 0.86; P value: 0.29), and approximately the same for MSI-high and obese BMI (HR, 1.00; P value: 0.98).

CONCLUSIONS

High prediagnosis BMI was associated with increased mortality; this association was consistent across participant subgroups, including strata of tumor molecular phenotype.

IMPACT

High BMI may attenuate the survival benefit otherwise observed with MSI-high tumors.

Obesity as a risk factor in cancer: A national consensus of the Spanish Society for the Study of Obesity and the Spanish Society of Medical Oncology

In the last few years, many prospective studies have demonstrated a clear association between obesity and cancers of the colon and rectum, breast in post-menopausal women, endometrium, kidney, oesophagus and pancreas. Obesity is also associated with a high risk of recurrence and cancer-related death. The pathophysiology of obesity involves various changes that may be implicated in the relationship between obesity and cancer, such as excess inflammatory cytokines and chronic inflammation, hyperinsulinaemia, insulin resistance, and raised leptin and oestrogens. The Spanish Society for the Study of Obesity and the Spanish Society of Medical Oncology have signed a cooperation agreement to work together towards reducing the impact of obesity in cancer. Preventing obesity prevents cancer.

Survivorship: healthy lifestyles, version 2.2014

Healthy lifestyle habits have been associated with improved health outcomes and quality of life and, for some cancers, a reduced risk of recurrence and death. The NCCN Guidelines for Survivorship therefore recommend that cancer survivors be encouraged to achieve and maintain a healthy lifestyle, with attention to weight management, physical activity, and dietary habits. This section of the NCCN Guidelines focuses on recommendations regarding physical activity in survivors, including assessment for the risk of exercise-induced adverse events, exercise prescriptions, guidance for resistance training, and considerations for specific populations (eg, survivors with lymphedema, ostomies, peripheral neuropathy). In addition, strategies to encourage health behavioral change in survivors are discussed.

KRAS and BRAF gene mutations and DNA mismatch repair status in Chinese colorectal carcinoma patients

AIM: To investigate gene mutations and DNA mismatch repair (MMR) protein abnormality in Chinese colorectal carcinoma (CRC) patients and their correlations with clinicopathologic features.

METHODS: Clinical and pathological information for 535 patients including 538 tumors was reviewed and recorded. Mutation analyses for exon 2 of KRAS gene and exon 15 of BRAF gene were performed by Sanger sequencing except that in 9 tumors amplification refractory mutation system PCR was used. Expression of MMR proteins including MHL1, MSH2, MSH6 and PMS2 was evaluated by immunohistochemistry. Correlations of KRAS and BRAF mutation status and the expression status of MMR proteins with age, gender, cancer stage, location, and histology were analyzed. Correlations between KRAS or BRAF mutations and MMR protein expression were also explored.

RESULTS: The overall frequencies of KRAS and BRAF mutations were 37.9% and 4.4%, respectively. KRAS mutations were more common in patients ≥ 50 years old (39.8% vs 22% in patients < 50 years old, P < 0.05). The frequencies of BRAF mutants were higher in tumors from females (6.6% vs males 2.8%, P < 0.05), located in the right colon (9.6% vs 2.1% in the left colon, 1.8% in the rectum, P < 0.01), with mucinous differentiation (9.8% vs 2.8% without mucinous differentiation, P < 0.01), or being poorly differentiated (9.5% vs 3.4% well/moderately differentiated, P < 0.05). MMR deficiency was strongly associated with proximal location (20.5% in the right colon vs 9.2% in the left colon and 5.1% in the rectum, P < 0.001), early cancer stage (15.0% in stages I-II vs 7.7% in stages III-IV, P < 0.05), and mucinous differentiation (20.2% vs 9.2% without mucin, P < 0.01). A higher frequency of MLH1/PMS2 loss was found in females (9.2% vs 4.4% in males, P < 0.05), and MSH2/MSH6 loss tended to be seen in younger (<50 years old) patients (12.0% vs 4.0% ≥ 50 years old, P < 0.05). MMR deficient tumors were less likely to have KRAS mutations (18.8% vs 41.7% in MMR proficient tumors, P < 0.05) and tumors with abnormal MLH1/PMS2 tended to harbor BRAF mutations (15.4% vs 4.2% in MMR proficient tumors, P < 0.05).

CONCLUSION: The frequency of sporadic CRCs having BRAF mutation, MLH1 deficiency and MSI in Chinese population may be lower than that in the Western population.

Etiologic field effect: reappraisal of the field effect concept in cancer predisposition and progression

The term 'field effect' (also known as field defect, field cancerization, or field carcinogenesis) has been used to describe a field of cellular and molecular alteration, which predisposes to the development of neoplasms within that territory. We explore an expanded, integrative concept, 'etiologic field effect', which asserts that various etiologic factors (the exposome including dietary, lifestyle, environmental, microbial, hormonal, and genetic factors) and their interactions (the interactome) contribute to a tissue microenvironmental milieu that constitutes a 'field of susceptibility' to neoplasia initiation, evolution, and progression. Importantly, etiological fields predate the acquisition of molecular aberrations commonly considered to indicate presence of filed effect. Inspired by molecular pathological epidemiology (MPE) research, which examines the influence of etiologic factors on cellular and molecular alterations during disease course, an etiologically focused approach to field effect can: (1) broaden the horizons of our inquiry into cancer susceptibility and progression at molecular, cellular, and environmental levels, during all stages of tumor evolution; (2) embrace host-environment-tumor interactions (including gene-environment interactions) occurring in the tumor microenvironment; and, (3) help explain intriguing observations, such as shared molecular features between bilateral primary breast carcinomas, and between synchronous colorectal cancers, where similar molecular changes are absent from intervening normal colon. MPE research has identified a number of endogenous and environmental exposures which can influence not only molecular signatures in the genome, epigenome, transcriptome, proteome, metabolome and interactome, but also host immunity and tumor behavior. We anticipate that future technological advances will allow the development of in vivo biosensors capable of detecting and quantifying 'etiologic field effect' as abnormal network pathology patterns of cellular and microenvironmental responses to endogenous and exogenous exposures. Through an 'etiologic field effect' paradigm, and holistic systems pathology (systems biology) approaches to cancer biology, we can improve personalized prevention and treatment strategies for precision medicine.

Tumor LINE-1 methylation level and microsatellite instability in relation to colorectal cancer prognosis

BACKGROUND

Hypomethylation in long interspersed nucleotide element-1 (LINE-1) and high-degree microsatellite instability (MSI-high) in colorectal cancer (CRC) have been associated with inferior and superior survival, respectively; however, it remains uncertain whether the prognostic association of LINE-1 hypomethylation differs by MSI status. We hypothesized that the adverse prognostic association of LINE-1 hypomethylation might be stronger in MSI-high CRCs than in microsatellite stable (MSS) CRCs.

METHODS

Utilizing 1211 CRCs in the Nurses' Health Study and the Health Professionals Follow-up Study, we examined patient survival according to LINE-1 hypomethylation status in strata of MSI status. A Cox proportional hazards model was used to compute multivariable CRC-specific mortality hazard ratios (HRs) for a 10% decrease in LINE-1 methylation level (range = 23.1-93.1%), adjusting for potential confounders, including CpG island methylator phenotype, and KRAS, BRAF, and PIK3CA mutations. Statistical tests (log-rank test, chi-square test, and likelihood ratio test) were two-sided.

RESULTS

In MSI-high cancers, the association of LINE-1 hypomethylation with higher mortality (HR = 2.45, 95% confidence interval [CI] = 1.64 to 3.66, P < .001) was stronger than that in MSS cancers (HR = 1.10, 95% CI = 0.98 to 1.24, P = .11) (P interaction < .001, between LINE-1 and MSI statuses). In MSI-high cases with CRC family history, the association of LINE-1 hypomethylation with higher mortality (HR = 5.13, 95% CI = 1.99 to 13.2; P < .001) was stronger than that in MSI-high cases without CRC family history (HR = 1.62, 95% CI = 0.89 to 2.94, P = .11) (P interaction = .02, between LINE-1 and CRC family history statuses).

CONCLUSIONS

The association of LINE-1 hypomethylation with inferior survival is stronger in MSI-high CRCs than in MSS CRCs. Tumor LINE-1 methylation level may be a useful prognostic biomarker to identify aggressive carcinomas among MSI-high CRCs.

Impact of obesity on the survival of patients with early-stage squamous cell carcinoma of the oral tongue

BACKGROUND

Although obesity increases risk and negatively affects survival for many malignancies, the prognostic implications in squamous cell carcinoma (SCC) of the oral tongue, a disease often associated with prediagnosis weight loss, are unknown.

METHODS

Patients with T1-T2 oral tongue SCC underwent curative-intent resection in this single-institution study. All patients underwent nutritional assessment prior to surgery. Body mass index (BMI) was calculated from measured height and weight and categorized as obese (≥ 30 kg/m(2) ), overweight (25-29.9 kg/m(2) ), or normal (18.5-24.9 kg/m(2) ). Clinical outcomes, including disease-specific survival, recurrence-free survival, and overall survival, were compared by BMI group using Cox regression.

RESULTS

From 2000 to 2009, 155 patients (90 men, 65 women) of median age 57 years (range, 18-86 years) were included. Baseline characteristics were similar by BMI group. Obesity was significantly associated with adverse disease-specific survival compared with normal weight in univariable (hazard ratio [HR] = 2.65, 95% confidence interval [CI] = 1.07-6.59; P = .04) and multivariable analyses (HR = 5.01; 95% CI = 1.69-14.81; P = .004). A consistent association was seen between obesity and worse recurrence-free survival (HR = 1.87; 95% CI = 0.90-3.88) and between obesity and worse overall survival (HR = 2.03; 95% CI = 0.88-4.65) though without reaching statistical significance (P = .09 and P = .10, respectively) in multivariable analyses.

CONCLUSIONS

In this retrospective study, obesity was an adverse independent prognostic variable. This association may not have been previously appreciated due to confounding by multiple factors including prediagnosis weight loss.

Microsatellite instability and BRAF mutation testing in colorectal cancer prognostication

BRAF mutation in colorectal cancer is associated with microsatellite instability (MSI) through its relationship with high-level CpG island methylator phenotype (CIMP) and MLH1 promoter methylation. MSI and BRAF mutation analyses are routinely used for familial cancer risk assessment. To clarify clinical outcome associations of combined MSI/BRAF subgroups, we investigated survival in 1253 rectal and colon cancer patients within the Nurses' Health Study and Health Professionals Follow-up Study with available data on clinical and other molecular features, including CIMP, LINE-1 hypomethylation, and KRAS and PIK3CA mutations. Compared with the majority subtype of microsatellite stable (MSS)/BRAF-wild-type, MSS/BRAF-mutant, MSI-high/BRAF-mutant, and MSI-high/BRAF-wild-type subtypes showed multivariable colorectal cancer-specific mortality hazard ratios of 1.60 (95% confidence interval [CI] =1.12 to 2.28; P = .009), 0.48 (95% CI = 0.27 to 0.87; P = .02), and 0.25 (95% CI = 0.12 to 0.52; P < .001), respectively. No evidence existed for a differential prognostic role of BRAF mutation by MSI status (P(interaction) > .50). Combined BRAF/MSI status in colorectal cancer is a tumor molecular biomarker for prognosic risk stratification.

Comparison of dietary and lifestyle habits among stage III and metastatic colorectal cancer patients: findings from CALGB 89803 and CALGB 80405

Self-administered questionnaires were completed by patients undergoing chemotherapy for stage III colon cancer (n=1095) and metastatic colorectal cancer (n=875). We describe the prevalence of a wide-range of health-related dietary patterns and lifestyle behaviors among colorectal cancer patients with stage III and metastatic disease and report notable similarities in these 2 cohorts.

BACKGROUND

Cancer patients often pursue lifestyle and dietary changes with the aim to improve outcomes. Using data from 2 large National Cancer Institute-sponsored clinical trials, we report on the dietary and lifestyle practices of patients receiving therapy for stage III colon or metastatic colorectal cancer.

PATIENTS AND METHODS

Self-administered questionnaires were completed by patients undergoing chemotherapy for stage III colon cancer (n=1095) and metastatic colorectal cancer (n=875). Descriptive statistical analyses were performed to evaluate anthropometrics, diet, and lifestyle in each cohort.

RESULTS

Median body mass index was comparable for stage III and metastatic patients (27.3 vs. 26.5 kg/m2). Stage III patients reported a modestly higher median level of physical activity than metastatic patients (4.6 vs. 3.4 metabolic equivalent task-hours per week). Ten percent of stage III and 9% of metastatic patients reported ongoing cigarette use. Avoidance of alcohol was reported by 47% of stage III and 43% of metastatic patients. Dietary patterns for both groups were comparable with more than 80% of stage III and metastatic patients failing to meet the recommended daily intake of vegetables, fruits, and milk products. Usage of at least 2 multivitamins per week was reported by 49% of stage III and 40% of metastatic patients. Two percent of stage III and 5% of metastatic patients reported vitamin D supplement use.

CONCLUSIONS

We observed notable similarities in dietary and lifestyle behaviors between stage III colon and metastatic colorectal cancer patients actively receiving chemotherapy. Future research should aim to elucidate the effect of these behaviors on patient outcomes.

Initial neutrophil lymphocyte ratio is superior to platelet lymphocyte ratio as an adverse prognostic and predictive factor in metastatic colorectal cancer

The prognostic, especially predictive, values of inflammation indexes in advanced colorectal cancer were not established. Therefore, the both values of neutrophil lymphocyte ratio (NLR) and platelet lymphocyte ratio (PLR) in patients with initially metastatic colorectal cancer (mCRC) were investigated and compared. Samples were collected from 243 patients who were initially diagnosed with mCRC between 2005 and 2010 in the Sun Yat-sen University Cancer Center. Elevated NLR (p < 0.001), PLR (p = 0.008), and CEA (p < 0.001) were identified as statistically significant poor prognostic factors for overall survival (OS), while only NLR (p = 0.029) and CEA (p < 0.001) were validated as independent predictors. Univariate analysis identified elevated NLR (p < 0.001), PLR (p = 0.023), and CEA (p < 0.001) as statistically significant poor predict factors for the progression-free survival (PFS) of first-line chemotherapy, while NLR (p = 0.013) and CEA (p = 0.001) were independent. In addition, we observed significantly different OS (p < 0.001) and PFS (p < 0.001) among patients who had elevations in both NLR and CEA levels and those having one elevation or neither elevation. NLR, PLR, and CEA were significant predictors of OS and PFS in mCRC. However, only NLR and CEA play as independent. When coupled with CEA, NLR may lead to improved prognostic predictors.

Short-term outcomes in obese patients after colectomy for adenocarcinoma at a bariatric center

INTRODUCTION

Obesity (body mass index ≥30) is associated with worse outcomes after colon cancer surgery. Most research, however, has been performed outside bariatric centers of excellence. We sought to determine the relationship between obesity and outcomes after colon cancer resection when performed at a center with bariatric expertise.

METHODS

We performed a retrospective review of 245 consecutive patients undergoing elective colectomy for adenocarcinoma at a single institution from 2008 to 2009. Body mass index, major and minor postoperative complications, tumor characteristics, lymph node yield, type of resection, and operating times were determined.

RESULTS

Complication rates, operative times, and lymph node counts were all similar between the two weight groups. Obese patients had similar tumor characteristics at all stages when compared with nonobese patients. On multivariate analysis, obesity did not correlate with tumor size, tumor differentiation, or presence of lymphovascular or perineural invasion.

CONCLUSION

We conclude that obese patients undergoing colon cancer resection at a bariatric center of excellence have similar tumor characteristics and equivalent short-term outcomes as do nonobese patients.

Association between body mass index and colorectal cancer: Recent research progress

Colorectal cancer (CRC) is a common digestive system disease posing a serious threat to people's health. There are about 1. 2 million new cases of CRC diagnosed worldwide each year, and the figure in China is 130 thousand. The socio-economic development and changes in diet and habits in China have led to a significant increase in both the incidence and mortality of CRC. The average age of onset of CRC in China is about 20 years old lower than that in Western countries, ranking second among all malignant tumors. The incidence and mortality of CRC in some developed regions of China, however, is close to those in Western developed countries. The development of CRC results from multiple factors, and nearly a quarter of patients with CRC could have avoided suffering from this disease by making favorable lifestyle habits. Nowadays, two-thirds of adults are fighting against overweight and obesity. Numerous recent studies indicate that high body mass index (BMI) is related with colorectal cancer. This article will review recent advances in understanding the relationship between BMI and CRC.