• Record: found
  • Abstract: found
  • Article: found
Is Open Access

Associations of Anthropometric Factors with KRAS and BRAF Mutation Status of Primary Colorectal Cancer in Men and Women: A Cohort Study

Read this article at

      There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


      Obesity is a well-established risk factor for colorectal cancer (CRC), and accumulating evidence suggests a differential influence of sex and anthropometric factors on the molecular carcinogenesis of the disease. The aim of the present study was to investigate the relationship between height, weight, bodyfat percentage, waist- and hip circumference, waist-hip ratio (WHR), body mass index (BMI) and CRC risk according to KRAS and BRAF mutation status of the tumours, with particular reference to potential sex differences. KRAS and BRAF mutations were analysed by pyrosequencing in tumours from 494 incident CRC cases in the Malmö Diet and Cancer Study. Hazard ratios of CRC risk according to anthropometric factors and mutation status were calculated using multivariate Cox regression models. While all anthropometric measures except height were associated with an increased risk of KRAS-mutated tumours, only BMI was associated with an increased risk of KRAS wild type tumours overall. High weight, hip, waist, WHR and BMI were associated with an increased risk of BRAF wild type tumours, but none of the anthropometric factors were associated with risk of BRAF-mutated CRC, neither in the overall nor in the sex-stratified analysis. In men, several anthropometric measures were associated with both KRAS-mutated and KRAS wild type tumours. In women, only a high WHR was significantly associated with an increased risk of KRAS-mutated CRC. A significant interaction was found between sex and BMI with respect to risk of KRAS-mutated tumours. In men, all anthropometric factors except height were associated with an increased risk of BRAF wild type tumours, whereas in women, only bodyfat percentage was associated with an increased risk of BRAF wild type tumours. The results from this prospective cohort study further support an influence of sex and lifestyle factors on different pathways of colorectal carcinogenesis, defined by KRAS and BRAF mutation status of the tumours.

      Related collections

      Most cited references 56

      • Record: found
      • Abstract: found
      • Article: not found

      Body-mass index and incidence of cancer: a systematic review and meta-analysis of prospective observational studies.

      Excess bodyweight, expressed as increased body-mass index (BMI), is associated with the risk of some common adult cancers. We did a systematic review and meta-analysis to assess the strength of associations between BMI and different sites of cancer and to investigate differences in these associations between sex and ethnic groups. We did electronic searches on Medline and Embase (1966 to November 2007), and searched reports to identify prospective studies of incident cases of 20 cancer types. We did random-effects meta-analyses and meta-regressions of study-specific incremental estimates to determine the risk of cancer associated with a 5 kg/m2 increase in BMI. We analysed 221 datasets (141 articles), including 282,137 incident cases. In men, a 5 kg/m2 increase in BMI was strongly associated with oesophageal adenocarcinoma (RR 1.52, p<0.0001) and with thyroid (1.33, p=0.02), colon (1.24, p<0.0001), and renal (1.24, p <0.0001) cancers. In women, we recorded strong associations between a 5 kg/m2 increase in BMI and endometrial (1.59, p<0.0001), gallbladder (1.59, p=0.04), oesophageal adenocarcinoma (1.51, p<0.0001), and renal (1.34, p<0.0001) cancers. We noted weaker positive associations (RR <1.20) between increased BMI and rectal cancer and malignant melanoma in men; postmenopausal breast, pancreatic, thyroid, and colon cancers in women; and leukaemia, multiple myeloma, and non-Hodgkin lymphoma in both sexes. Associations were stronger in men than in women for colon (p<0.0001) cancer. Associations were generally similar in studies from North America, Europe and Australia, and the Asia-Pacific region, but we recorded stronger associations in Asia-Pacific populations between increased BMI and premenopausal (p=0.009) and postmenopausal (p=0.06) breast cancers. Increased BMI is associated with increased risk of common and less common malignancies. For some cancer types, associations differ between sexes and populations of different ethnic origins. These epidemiological observations should inform the exploration of biological mechanisms that link obesity with cancer.
        • Record: found
        • Abstract: found
        • Article: not found

        Genetic alterations during colorectal-tumor development.

        Because most colorectal carcinomas appear to arise from adenomas, studies of different stages of colorectal neoplasia may shed light on the genetic alterations involved in tumor progression. We looked for four genetic alterations (ras-gene mutations and allelic deletions of chromosomes 5, 17, and 18) in 172 colorectal-tumor specimens representing various stages of neoplastic development. The specimens consisted of 40 predominantly early-stage adenomas from 7 patients with familial adenomatous polyposis, 40 adenomas (19 without associated foci of carcinoma and 21 with such foci) from 33 patients without familial polyposis, and 92 carcinomas resected from 89 patients. We found that ras-gene mutations occurred in 58 percent of adenomas larger than 1 cm and in 47 percent of carcinomas. However, ras mutations were found in only 9 percent of adenomas under 1 cm in size. Sequences on chromosome 5 that are linked to the gene for familial adenomatous polyposis were not lost in adenomas from the patients with polyposis but were lost in 29 to 35 percent of adenomas and carcinomas, respectively, from other patients. A specific region of chromosome 18 was deleted frequently in carcinomas (73 percent) and in advanced adenomas (47 percent) but only occasionally in earlier-stage adenomas (11 to 13 percent). Chromosome 17p sequences were usually lost only in carcinomas (75 percent). The four molecular alterations accumulated in a fashion that paralleled the clinical progression of tumors. These results are consistent with a model of colorectal tumorigenesis in which the steps required for the development of cancer often involve the mutational activation of an oncogene coupled with the loss of several genes that normally suppress tumorigenesis.
          • Record: found
          • Abstract: found
          • Article: not found

          Systematic review of microsatellite instability and colorectal cancer prognosis.

          A number of studies have investigated the relationship between microsatellite instability (MSI) and colorectal cancer (CRC) prognosis. Although many have reported a better survival with MSI, estimates of the hazard ratio (HR) among studies differ. To derive a more precise estimate of the prognostic significance of MSI, we have reviewed and pooled data from published studies. Studies stratifying survival in CRC patients by MSI status were eligible for analysis. The principal outcome measure was the HR. Data from eligible studies were pooled using standard techniques. Thirty-two eligible studies reported survival in a total of 7,642 cases, including 1,277 with MSI. There was no evidence of publication bias. The combined HR estimate for overall survival associated with MSI was 0.65 (95% CI, 0.59 to 0.71; heterogeneity P = .16; I(2) = 20%). This benefit was maintained restricting analyses to clinical trial patients (HR = 0.69; 95% CI, 0.56 to 0.85) and patients with locally advanced CRC (HR = 0.67; 95% CI, 0.58 to 0.78). In patients treated with adjuvant fluorouracil (FU) CRCs with MSI had a better prognosis (HR = 0.72; 95% CI, 0.61 to 0.84). However, while data are limited, tumors with MSI derived no benefit from adjuvant FU (HR = 1.24; 95% CI, 0.72 to 2.14). CRCs with MSI have a significantly better prognosis compared to those with intact mismatch repair. Additional studies are needed to further define the benefit of adjuvant chemotherapy in locally advanced tumors with MSI.

            Author and article information

            [1 ]Department of Clinical Sciences, Division of Oncology and Pathology, Lund University, Skåne University Hospital, Lund, Sweden
            [2 ]Department of Surgery, Skåne University Hospital, Malmö, Sweden
            [3 ]Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
            [4 ]Department of Clinical Sciences, Malmö, Lund University, Skåne University Hospital, Malmö, Sweden
            [5 ]Department of Plastic Surgery, Skåne University Hospital, Malmö, Sweden
            University of Bari & Consorzio Mario Negri Sud, Italy
            Author notes

            Competing Interests: The authors have declared that no competing interests exist.

            Conceived and designed the experiments: KJ. Performed the experiments: JB BN SW MS. Analyzed the data: JB SW JE JM KJ. Contributed reagents/materials/analysis tools: JB JE KJ JM. Wrote the paper: JB.

            Role: Editor
            PLoS One
            PLoS ONE
            PLoS ONE
            Public Library of Science (San Francisco, USA )
            11 June 2014
            : 9
            : 6
            24918610 4053324 PONE-D-13-48451 10.1371/journal.pone.0098964

            This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

            Pages: 11
            This study was supported by grants from the Knut and Alice Wallenberg Foundation, the Swedish Cancer Society, the Gunnar Nilsson Cancer Foundation, Region Skåne and the Research Funds of Skåne University Hospital. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
            Research Article
            Biology and Life Sciences
            Evolutionary Biology
            Population Genetics
            Medicine and Health Sciences
            Cancer Epidemiology
            Molecular Epidemiology
            Gastroenterology and Hepatology
            Gastrointestinal Cancers
            Cancer Risk Factors
            Lifestyle Causes of Cancer
            Basic Cancer Research
            People and Places
            Research and Analysis Methods
            Research Design
            Clinical Research Design
            Cohort Studies
            Prospective Studies



            Comment on this article