***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: PURPOSE The impact of body mass index ( BMI ) on survival after colorectal cancer diagnosis is poorly understood . This study assessed the association of pre- and postdiagnosis BMI with all-cause and cause-specific survival among men and women diagnosed with colorectal cancer in a prospect i ve cohort . PATIENTS AND METHODS Participants in the Cancer Prevention Study -II Nutrition Cohort  reported weight and other risk factor information via a self-administered question naire at baseline in 1992 to 1993 . Up date d information on current weight and incident cancer was reported via periodic follow-up question naires . This analysis includes 2,303 cohort participants who were diagnosed with nonmetastatic colorectal cancer between baseline and mid 2007 and were observed for mortality from diagnosis through December 2008 . RESULTS A total of 851 participants with colorectal cancer  died during the 16-year follow-up period , including 380 as a result of colorectal cancer and 153 as a result of cardiovascular disease ( CVD ) . In analyses of prediagnosis BMI ( weight reported at baseline in 1992 to 1993 ; mean , 7 years before colorectal cancer diagnosis ) , obese BMI ( ≥ 30 kg/m(2 ) ) relative to normal BMI ( 18.5 to 24.9 kg/m(2 ) ) was associated with higher risk of mortality result ing from all causes ( relative risk [ RR ] , 1.30 ; 95 % CI , 1.06 to 1.58 ) , colorectal cancer ( RR , 1.35 ; 95 % CI , 1.01 to 1.80 ) , and CVD ( RR , 1.68 ; 95 % CI , 1.07 to 2.65 ) . Postdiagnosis BMI ( based on weight reported ; mean , 1.5 years after diagnosis ) was not associated with all-cause or cause-specific mortality . CONCLUSION This study suggests that prediagnosis BMI , but not postdiagnosis BMI , is an important predictor of survival among patients with nonmetastatic colorectal cancer 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 prospect i ve 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 Background : We hypothesized that precancer anthropometric variables are associated with mortality among women who developed colon cancer in a prospect i ve cohort , the Iowa Women 's Health Study ( IWHS ) . Methods : From 1986 to 2005 , 1,096 incident cases of colon cancer were identified ( mean age at diagnosis , 73 years ) .  Anthropometric characteristics were self-measured before colon cancer diagnosis ( in 1986 ) . Cox proportional hazards regression was used to estimate hazard ratios ( HR ) and 95 % confidence intervals ( 95 % CI ) for all-cause and colon-cancer mortality , adjusted for age at cancer diagnosis , stage , education , smoking status , and pack-years of smoking . Results : During the follow-up of up to 20 years , 493 women died ; 289 had colon cancer as the underlying cause . The HRs of all-cause death were increased for the highest versus lowest tertile for weight ( HR , 1.39 ; 95 % CI , 1.10 - 1.76 ; P trend = 0.005 ) ; waist to hip ratio ( WHR ; HR , 1.36 ; 95 % CI , 1.08 - 1.72 ; P trend = 0.008 ) , and waist ( HR , 1.45 ; 95 % CI , 1.15 - 1.82 ; P trend = 0.001 ) . Compared with that for body mass index ( BMI ) of 18.5 to 24.9 kg/m2 , HRs were increased for BMI ≥30 kg/m2 ( HR , 1.45 ; 95 % CI , 1.14 - 1.85 ) and for the few women with BMI < 18.5 kg/m2 ( HR , 1.89 ; 95 % CI , 1.01 - 3.53 ) . Colon cancer mortality was positively associated with WHR and waist : HR , 1.37 ( 95 % CI , 1.02;1.85 ; P trend = 0.04 ) and 1.34 ( 95 % CI , 1.01 - 1.80 ; P trend = 0.05 ) , respectively , for the highest versus lowest tertile . Conclusion : Greater precancer anthropometric measures and BMI < 18.5 kg/m2 predicted poorer survival among colon cancer patients .  Higher abdominal adiposity measured by WHR and waist was associated with increased risk of colon cancer death . Impact : Prediagnostic obesity may be a modifiable risk factor for death in colon cancer patients . Cancer Epidemiol Biomarkers Prev ; 19(9 ) ; 2229–37 . © 2010 AACR Background It remains unclear whether the increased risk of colorectal cancer ( CRC ) associated with obesity differs by gender , distribution of fat , tumour location and clinical ( TNM ) stage . The primary aim of this study was to examine these associations in 584 incident colorectal cancer cases from a Swedish prospect i ve population -based cohort including 28098 men and women . Methods Seven anthropometric factors ; height , weight , bodyfat percentage , hip circumference , waist circumference , BMI and waist-hip ratio ( WHR ) were categorized into quartiles of baseline anthropometric measurements . Relative risks of CRC , total risk as well as risk of different TNM stages , and risk of tumours located to the colon or rectum , were calculated for all cases , women and men , respectively , using multivariate Cox regression models . Results Obesity , as defined by all anthropometric variables , was significantly associated with an overall increased risk of CRC  in both women and men . While none of the anthropometric measures was significantly associated with risk of tumour (T)-stage 1 and 2 tumours , all anthropometric variables were significantly associated with an increased risk of T-stage 3 and 4 , in particular in men . In men , increasing quartiles of weight , hip , waist , BMI and WHR were significantly associated with an increased risk of lymph node positive ( N1 and N2 ) disease , and risk of both non-metastatic ( M0 ) and metastatic ( M1 ) disease . In women , there were no or weak associations between obesity and risk of node-positive disease , but statistically significant associations between increased weight , bodyfat percentage , hip , BMI and M0 disease . Interestingly , there was an increased risk of colon but not rectal cancer in men , and rectal but not colon cancer in women , by increased measures of weight , hip- , waist circumference and bodyfat percentage . Conclusions This study is the first to show a relationship between obesity , measured as several different anthropometric factors , and an increased risk of colorectal cancer of more advanced clinical stage , in particular in men . These findings suggest that risk of CRC differs according to the method of characterising obesity , and also according to gender , location , and tumour stage There are few reports on factors that determine survival in advanced gastrointestinal cancer with weight loss . In these patients ( n = 91 , median weight loss 16.6 % ) , we prospect ively examined the importance of metastatic spread , anthropometry , blood parameters , Karnofsky performance status , appetite , and the acute-phase response as predictors of survival . Survival was calculated from date of assessment to the most recent clinic attendance ( ≥30 mo ) or until death . On multivariate analysis , metastatic spread ( p < 0.05 ) , Karnofsky performance status ( p < 0.01 ) , and C-reactive protein concentration ( p < 0.001 ) had independent prognostic value . In locally advanced disease ( n = 64 ) , Karnofsky performance status and C-reactive protein concentration remained significant . There was a significantly lower survival in patients with an acute-phase response ( median 136 days ) than in patients with no response ( median 466 days ; p < 0.01 ) . Performance status and the acute-phase response are associated , independent of weight loss , with survival duration in advanced gastrointestinal cancer patients Summary Background Local recurrence rates in operable rectal cancer are improved by radiotherapy ( with or without chemotherapy ) and surgical techniques such as total mesorectal excision . However , the contributions of surgery and radiotherapy to outcomes are unclear . We assessed the effect of the involvement of the circumferential resection margin and the plane of surgery achieved . Methods In this prospect i ve study , the plane of surgery achieved and the involvement of the circumferential resection margin were assessed by local pathologists , using a st and ard pathological protocol in 1156 patients with operable rectal cancer from the CR07 and NCIC-CTG CO16 trial , which compared short-course ( 5 days ) preoperative radiotherapy and selective postoperative chemoradiotherapy , between March , 1998 , and August , 2005 . All analyses were by intention to treat . This trial is registered , number IS RCT N 28785842 . Findings 128 patients ( 11 % ) had involvement of the circumferential resection margin , and the plane of surgery achieved was classified as good ( mesorectal ) in 604 ( 52 % ) , intermediate ( intramesorectal ) in 398 ( 34 % ) , and poor ( muscularis propria plane ) in 154 ( 13 % ) . We found that both a negative circumferential resection margin and a superior plane of surgery achieved were associated with low local recurrence rates . Hazard ratio ( HR ) was 0·32 ( 95 % CI 0·16–0·63 , p=0·0011 ) with 3-year local recurrence rates of 6 % ( 5–8 % ) and 17 % ( 10–26 % ) for patients who were negative and positive for circumferential resection margin , respectively . For plane of surgery achieved , HRs for mesorectal and intramesorectal groups compared with the muscularis propria group were 0·32 ( 0·16–0·64 ) and 0·48 ( 0·25–0·93 ) , respectively . At 3 years , the estimated local recurrence rates were 4 % ( 3–6 % ) for mesorectal , 7 % ( 5–11 % ) for intramesorectal , and 13 % ( 8–21 % ) for muscularis propria groups . The benefit of short-course preoperative radiotherapy did not differ in the three plane of surgery groups ( p=0·30 for trend ) . Patients in the short-course preoperative radiotherapy group who had a resection in the mesorectal plane had a 3-year local recurrence rate of only 1 % . Interpretation In rectal cancer , the plane of surgery achieved is an important prognostic factor for local recurrence .  Short-course preoperative radiotherapy reduced the rate of local recurrence for all three plane of surgery groups , almost abolishing local recurrence in short-course preoperative radiotherapy patients who had a resection in the mesorectal plane . The plane of surgery achieved should therefore be assessed and reported routinely . Funding Medical Research Council ( UK ) and the National Cancer Institute of Canada Background and purpose Previous studies have shown that physical inactivity and obesity are risk factors for the development of colorectal cancer . However , controversy exists regarding the influence of these factors on survival in colorectal cancer patients . We evaluated the impact of recreational physical activity and body mass index ( BMI )  before and after colorectal cancer diagnosis on disease-specific mortality and all-cause mortality . Patients and methods This prospect i ve cohort study included 1,339 women enrolled in the Women ’s Health Initiative study who were diagnosed with colorectal cancer subsequent to study enrollment .  BMI and recreational physical activity  were measured before cancer diagnosis 
    Output:
    
Both obese and underweight patients with colorectal cancer have an increased risk of all-cause mortality , cancer-specific mortality , disease recurrence and worse disease-free survival compared to normal weight patients