Impact of obesity on operation performed, complications, and long-term outcomes in terms of restoration of intestinal continuity for patients with mid and low rectal cancer

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.

The role of transanal compared to laparoscopic total mesorectal excision (taTME vs. lapTME) for the treatment of mid-low rectal cancer in obese patients: outcomes of a multicenter propensity-matched analysis

To compare the rate of sphincter-saving interventions between transanal and laparoscopic Total Mesorectal Excision in this particular group of patients. A multicentre observational study was conducted using a prospective database, including patients diagnosed with rectal cancer below the peritoneal reflection and BMI ≥ 30 kg/m2, who underwent minimally invasive elective surgery over a 5-year period. Exclusion criteria were (1) sphincter and/or puborectalis invasion; (2) multi-visceral resections; (3) palliative surgeries. The study population was divided into two groups according to the intervention: transanal or laparoscopic total mesorectal excision. The primary outcome was the rate of sphincter-saving surgery. Secondary outcomes included conversion, postoperative complications, quality of the specimen, and survival. A total of 93 patients were included; 40 (43%) transanal total mesorectal excision were compared to 53 (57%) laparoscopic. In addition, 35 cases of transanal approach were case-matched with an equal number of laparoscopic approaches, based on gender, tumor's height, and neoadjuvant therapy. In both groups, 43% of the patients had low rectal cancer; however, the rate of sphincter-saving surgery was significantly higher in the transanal group (97% vs. 71%, p = 0.003). There were no conversions to open surgery in the transanal group, compared to 2 cases in the laparoscopic group (6%) (p = 0.246). The percentage of major complications was similar, including the rate of anastomotic leakage (10% transanal vs. 19% laparoscopic, p = 0.835). In our experience, higher percentages of sphincter-saving procedures and lower conversion rates are potential benefits of using the transanal approach in a complex surgical setting population of obese patients with mid-low rectal tumors when compared to laparoscopic.

Impact of obesity on patients undergoing surgery for rectal cancer in Australia and New Zealand

PURPOSE

Patients with obesity undergoing rectal cancer surgery may have an increased risk of developing complications, though evidence is inconclusive. The aim of this study was to determine the direct impact of obesity on postoperative outcomes using data from a large clinical registry.

METHOD

The Binational Colorectal Cancer Audit registry was used to identify patients who underwent rectal cancer surgery in Australia and New Zealand from 2007-2021. Primary outcomes were inpatient surgical and medical complications. Logistic regression models were developed to describe the association between body-mass index (BMI) and outcomes.

RESULTS

Among 3,708 patients (median age 66 years [IQR 56.75-75], 65.0% male), 2.0% had a BMI < 18.5 kg/m2, 35.4% had a BMI of 18.5-24.9 kg/m2, 37.6% had a BMI of 25.0-29.9 kg/m2, 16.7% had a BMI of 30.0-34.9 kg/m2, and 8.2% had a BMI ≥ 35.0 kg/m2. Surgical complications occurred in 27.7% of patients with a BMI of 18.5-24.9 kg/m2, 26.6% of patients with a BMI of 25.0-29.9 kg/m2 (OR 0.91, 95% CI 0.76-1.10), 28.5% with a BMI of 30.0-34.9 kg/m2 (OR 0.96, 95% CI 0.76-1.21), and 33.2% with a BMI ≥ 35.0 kg/m2 (OR 1.27, 95% CI 0.94-1.71). Modelling BMI as a continuous variable confirmed a J-shaped relationship. The association between BMI and medical complications was more linear.

CONCLUSION

Risk of postoperative complications is increased in patients with obesity undergoing rectal cancer surgery.

Associations of muscle and adipose tissue parameters with long-term outcomes in middle and low rectal cancer: a retrospective cohort study

OBJECTIVE

To investigate the role of preoperative body composition analysis for muscle and adipose tissue distribution on long-term oncological outcomes in patients with middle and low rectal cancer (RC) who received curative intent surgery.

METHODS

A total of 155 patients with middle and low rectal cancer who underwent curative intent surgery between January 2014 and December 2016 were included for the final analysis. Skeletal muscle area (SMA), skeletal muscle radiodensity (SMD), visceral fat area (VFA) and mesorectal fat area (MFA) were retrospectively measured using preoperative CT images. To standardize the area according to patient stature, SMA was divided by the square of the height (m²) and the skeletal muscle mass index (SMI, cm²/m²) was obtained. Each median values of the distribution in male and female served as cut-off point for SMI, SMD, VFA, and MFA, respectively. Univariate and multivariate analysis were performed to evaluate the association between body composition and long-term oncological outcomes. Overall survival (OS) measured in months from the day of primary surgery until death for any cause. Disease-free survival (DFS) was defined as the interval between surgery and tumor recurrence. The Kaplan-Meier method with log-rank testing was used to validate prognostic biomarkers. Intraclass correlation coefficient (ICC) was used to evaluate interobserver and intraobserver reproducibility for SMA, SMD, MFA,VFA.

RESULTS

During the follow-up period, 42 (27.1%) patients had tumor recurrence; 21 (13.5%) patients died. The sex-specific median value of SMI was 28.6 cm²/m² for females and 48.2 cm²/m² for males. The sex-specific median value of SMD was 34.7 HU for females and 37.4 HU for males. The sex-specific median value of VFA was 123.1 cm² for females and 123.2 cm² for males. The sex-specific median value of MFA was 13.8 cm² for females and 16.0 cm² for males. In the Cox regression multivariate analysis, SMI (P = 0.036), SMD (P = 0.022), and postoperative complications grades (P = 0.042) were significantly different between death group and non-death group; SMD (P = 0.011) and MFA (P = 0.022) were significantly different between recurrence group and non-recurrence group. VFA did not show any significant differences. By the Kaplan-Meier method with log-rank testing, DFS was significantly longer in patients with high-MFA (P = 0.028) and shorter in patients with low-SMD (P = 0.010), OS was significantly shorter in patients with low-SMI (P = 0.034) and low-SMD (P = 0.029).

CONCLUSIONS

Quantitative evaluation of skeletal muscle mass and adipose tissue distributions at initial diagnosis were important predictors for long-term oncologic outcomes in RC patients. SMD and SMI were independent factors for predicting OS in patients with middle and low rectal cancer who had radical surgery. SMD and MFA were independent factors for predicting DFS in patients with middle and low rectal cancer who had radical surgery.

Impact of obesity on morbidity and oncologic outcomes after total mesorectal excision for mid and low rectal cancer

BACKGROUND

A recent meta-analysis showed that obesity increased the conversion rate and postoperative morbidity of rectal cancer surgery, but did not influence pathological results. However, this meta-analysis included patients with cancer of the upper rectum and had many biases. The aim of the present retrospective study was to investigate the impact of obesity, defined as a body mass index (BMI) ≥ 30 kg/m², on postoperative morbidity and short- and long-term oncologic outcomes of total mesorectal excision for mid and low rectal cancer in consecutive patients.

METHODS

This study included all eligible patients who were operated on for mid and lower rectal cancer between 1999 and 2018 in our hospital. We compared 90-day postoperative morbidity and mortality, and short- and long-term oncologic outcomes between obese and non-obese patients.

RESULTS

Three hundred and ninety patients [280 males, mean age 65.7 ± 11.3 years, 59 obese individuals (15.1%)] were included. There was no difference in the 90-day mortality rate between obese and non-obese groups (p = 0.068). There was a difference in the overall 90-day morbidity rate between the obese and non-obese groups that disappeared after propensity score matching of the patients. There was no difference in short-term oncological parameters, with a median follow-up of 43 (20-84) months, and there were no significant differences in disease-free and overall survival between obese and non-obese patients (p = 0.42 and p = 0.11, respectively).

CONCLUSIONS

Obesity does not affect the 90-day morbidity rate, or short- and long-term oncologic results in patients operated on for mid and lower rectal cancer.

Impact of preoperative body mass index and weight loss on morbidity and mortality following colorectal cancer-a retrospective cohort study

PURPOSE

Body weight and preoperative weight loss (WL) are controversially discussed as risk factors for postoperative morbidity and mortality in colorectal cancer surgery. The objective of this study is to determine whether body mass index (BMI) or WL is associated with a higher postoperative complication rate.

METHODS

In this retrospective cohort study, data analysis of 1241 consecutive patients undergoing colorectal cancer surgery in an 11-year period was performed. The main outcome measures were wound infections (WI), anastomotic leakages (AL), and in-house mortality.

RESULTS

A total of 697 (56%) patients with colon and 544 (44%) with rectum carcinoma underwent surgery. The rate of WI for each location increased with rising BMI. The threshold value was 28.8 kg/m2. Obese patients developed significantly more WI than normal-weight patients did following rectal resection (18.0% vs. 8.2%, p = 0.018). Patients with preoperative WL developed significantly more AL following colon resections than did patients without preoperative WL (6.2% vs. 2.5%, p = 0.046). In-house mortality was significantly higher in obese patients following colon resections than in overweight patients (4.3% vs. 0.4%, p = 0.012). Regression analysis with reference to postoperative in-house mortality revealed neither increased BMI nor WL as an independent risk factor.

CONCLUSIONS

Increased preoperative BMI is associated with a higher WI rate. AL rate after colon resection was significantly higher in patients showing preoperative WL. Preoperative BMI and WL are therefore risk factors for postoperative morbidity in this study. Nevertheless, this has to be further clarified by means of prospective studies. Trial registration DRKS00025359, 21.05.2021, retrospectively registered.

Visceral-to-Subcutaneous Fat Ratio Is a Potential Predictor of Postoperative Complications in Colorectal Cancer

Background

Colorectal cancer (CRC) is one of the most common malignant tumors. Surgery is the primary treatment for CRC. Recent studies have shown that visceral-to-subcutaneous fat ratio (VSR) may be a potential indicator of risk. The aim of the present study was to determine whether VSR is a suitable predictor of the impact of postoperative complications in CRC.

Material/Methods

Clinical data from 129 patients were analyzed retrospectively. All patients underwent laparoscopic surgery for CRC. Preoperative imaging was used to quantify VSR. The primary outcome was 30-day postoperative complications. Multivariate logistic regression was used to determine the association between obesity indexes and postoperative complications.

Results

There were 129 patients who underwent primary resections of colorectal cancer. At 30 days after surgery, postoperative complications had occurred in 33 (25.6%) patients. VSR was significantly associated with postoperative complications in multivariate analysis (P=0.032, OR 6.103, 95% CI 1.173–31.748). In ROC analysis, VSR was a potential predictor of complications (AUC 0.650). A cutoff value of VSR ≥0.707 was associated with 60% sensitivity and 29% specificity for postoperative complications. Patients with VSR ≥0.707 had 41.7% risk of morbidity, whereas those with <0.707 had 16.0% risk (P=0.001).

Conclusions

Our study shows that VSR is superior to VFA for prediction of the risk of complications following CRC laparoscopic surgery. We have also identified the optimal cutoff values for the use of VSR for this purpose. Measurement of VSR and identifying patients with increased risk of postoperative complications facilitate making perioperative decisions.

The impact of anthropometric parameters on colorectal cancer prognosis: A systematic review and meta-analysis

BACKGROUND & AIMS

Our study aims to clarify the relationship between weight parameters and colorectal cancer outcomes.

METHODS

NCBI, Embase, Cochrane, and Web of Science were searched from inception to December 2019. Studies reporting colorectal cancer (CRC) mortality, recurrence, disease-free survival, overall survival, overall mortality stratified by pre-diagnosis BMI or post-diagnosis weight change, were included in the analysis. Random effects analysis was performed for all outcomes, with heterogeneity assessed by the I² statistic.

RESULTS

Our meta-analysis included 45 studies encompassing 607,266 patients. Obesity was associated with increased odds of overall mortality and CRC-specific mortality compared to normal weight (p < 0.001). Patients with underweight BMI had increased odds of CRC-specific mortality compared to normal BMI but were not significantly different from obese BMI.

CONCLUSIONS

Obese and underweight BMI are associated with increased CRC-specific and overall mortality compared to normal BMI. Long term prognosis was similar for patients with obese and underweight BMI.

Oncologic evaluation of obesity as a factor in patients with rectal cancer undergoing laparoscopic surgery: a propensity-matched analysis using body mass index

Purpose

This study evaluated the oncologic impact of obesity, as determined by body mass index (BMI), in patients who underwent laparoscopic surgery for rectal cancer.

Methods

The records of 483 patients with stage I-III rectal cancer who underwent laparoscopic surgery between June 2003 and December 2011 were reviewed. A matching model based on BMI was constructed to balance obese and nonobese patients. Cox hazard regression models for overall survival (OS) and disease-free survival (DFS) were used for multivariate analyses. Additional analysis using visceral fat area (VFA) measurement was performed for matched patients. The threshold for obesity was BMI ≥ 25 kg/m² or VFA ≥ 130 cm².

Results

The score matching model yielded 119 patients with a BMI ≥ 25 kg/m² (the obese group) and 119 patients with a BMI < 25 kg/m² (the nonobese group). Surgical outcomes including operation time, estimated blood loss, nil per os periods, and length of hospital stay did not differ between the obese and the nonobese group. The retrieved lymph node numbers and pathologic CRM positive rate were also similar in between the 2 groups. After a median follow-up of 48 months (range, 3-126 months), OS and DFS rates were similar between the 2 groups. A tumor location-adjusted model for overall surgical complications showed that a BMI ≥ 25 kg/m² were not risk factors. Multivariable analyses for OS and DFS showed no significant association with a BMI ≥ 25 kg/m².

Conclusion

Obesity was not associated with long-term oncologic outcomes in patients undergoing laparoscopic surgery for rectal cancer in the Asian population.

Quantitative assessment of mesorectal fat: new prognostic biomarker in patients with mid-to-lower rectal cancer

OBJECTIVES

To investigate the impact of mesorectal fat area (MFA) on oncologic outcomes in patients with mid-to-lower rectal cancer who received curative-intent surgery.

METHODS

Patients with mid-to-lower rectal cancer who underwent preoperative abdominopelvic computed tomography (CT) and curative-intent surgery in 2011 were divided into two groups by tumour recurrence (group A) or no recurrence (group B) during a 5-year follow-up. Visceral fat area (VFA) and MFA were measured on preoperative CT and cutoff values were calculated using the Youden index. Univariate and multivariate regression analyses including BMI, VFA, and MFA were performed to investigate meaningful prognostic biomarkers. The Kaplan-Meier method with log-rank testing was used to validate prognostic biomarkers.

RESULTS

Group A contained 42 patients and group B had 155 patients. Cutoff values were 25 kg/m² for BMI, 130 cm² for VFA, and 10 cm² for MFA using the Youden index. On multivariate Cox regression analysis, MFA (odds ratio [OR] = 0.426, p = 0.010), TNM stage (p = 0.027), and perioperative complication grade (p = 0.028) were significantly different between groups. BMI and VFA did not show significant differences. By the Kaplan-Meier method with log-rank testing, disease-free survival (DFS) was significantly longer in patients with MFA ≥10 cm² compared to patients with MFA <10 cm² (p = 0.021), with no significant difference in overall survival (OS).

CONCLUSIONS

MFA was an independent biomarker for predicting DFS in patients who underwent curative-intent surgery for mid-to-lower rectal cancer.

KEY POINTS

• Mesorectal fat area is associated with the prognosis of rectal cancer patients. • Mesorectal fat area can be calculated easily in pre-operative CT scan. • Predicting prognosis of the cancer patient before operation is important.

Visceral fat area, not body mass index, predicts postoperative 30-day morbidity in patients undergoing colon resection for cancer

PURPOSE

Colectomy for cancer in obese patients is technically challenging and may be associated with worse outcomes. Whether visceral obesity, as measured on computed tomography, is a better predictor of complication than body mass index (BMI) or determines long-term oncologic outcomes has not been well characterized. This study examines the association between derived anthropometrics and postoperative complication and long-term oncologic outcomes.

METHODS

Retrospective review of patients undergoing elective colectomy for cancer at a single tertiary-care center from 2010 to 2016. Adipose tissue distribution measurements, including visceral fat area (VFA), were determined from preoperative imaging. The primary outcome was 30-day postoperative complication; secondary outcomes included overall and disease-free survival. Multivariable logistic regression was performed to determine association between obesity metrics and outcome.

RESULTS

Two hundred and sixty-four patients underwent 266 primary resections of colon cancer. Twenty-eight patients (10.5%) developed major morbidity (Clavien-Dindo grade ≥ III). VFA but not BMI was significantly associated with morbidity in multivariate analysis (p = 0.004, odds ratio 1.99, 95% confidence interval 1.25-3.19). No other imaging-derived anthropometric was associated with increased morbidity. In receiver operating characteristic analysis, VFA was predictive of major morbidity (area under curve 0.660). A cutoff value of VFA ≥ 191 cm² was associated with 50% sensitivity and 76% specificity for predicting major morbidity. Patients with VFA ≥ 191cm² had 19.4% risk of morbidity, whereas those with < 191 cm² had 7.2% risk (relative risk ratio 2.69, unadjusted p = 0.004). Neither VFA nor BMI was associated with overall or disease-free survival.

CONCLUSION

VFA but not BMI predicts morbidity following elective surgery for colon cancer.

Effect of continuity nursing on wound healing, complications, and self-care ability in patients after gastrointestinal surgery for colorectal cancer

AIM

To evaluate the influence of continuity nursing on self-care ability, complications, and wound healing in patients with colorectal stoma after gastrointestinal surgery.

METHODS

We selected 120 patients who were diagnosed with colorectal cancer and underwent Miles surgery from May 2016 to May 2017 at Traditional Chinese Medicine Hospital of Zhuji City. These patients were randomly divided into an observation group and a control group, with 60 cases in each group. Both groups were given routine nursing care, and the observation group was additionally given continuity nursing care. The ESCA self-care scale was used to evaluate the self-care ability of patients in the two groups, the QLO-C30 life scale was used to score the daily life, and postoperative complications and stoma healing were also evaluated.

RESULTS

The self-care ability scores were significantly better in male patients than in females (P < 0.05), and self-care ability did not correlate with living conditions (P > 0.05). The self-concept, self-care, responsibility, self-care skills, health knowledge, and ESCA score of the observation group were significantly better than those of the control group at 4.5 mo after the operation (P < 0.01). In the control group, the incidence of complications such as stoma edema, stoma stenosis, stoma loss, and dermatitis around the stoma was significantly higher in the control group than in the observation group (P < 0.05). The scores of cognitive function, role function, physical function, and social function of the observation group were significantly higher than those of the control group at 4.5 mo after the operation (P < 0.01).

CONCLUSION

Continuity nursing care can effectively improve the self-care ability, reduce the incidence of postoperative complications, and improve quality of daily life in patients after Miles colostomy for colorectal cancer.

Obesity does not affect peri- and postoperative outcomes of transabdominal laparoscopic adrenalectomy

Laparoscopic adrenalectomy is the gold standard procedure for most adrenal tumors. Obesity is considered as a risk factor for surgical complications. This study aimed to evaluate whether obesity affects peri- and postoperative outcomes of transabdominal laparoscopic adrenalectomy using body mass index (BMI). This retrospective study included 98 patients who underwent transabdominal laparoscopic adrenalectomy between January 2011 and December 2016. We divided the patients into 2 groups: non-obese group (BMI < 25 kg/m2) and obese group (BMI ≥ 25 kg/m2). We assessed perioperative outcomes and postoperative complications between the groups. A total of 98 patients were analyzed (70 without obesity and 28 with obesity). There were no significant differences between the non-obese and obese groups regarding operative time (111 vs 107 min; p = 0.795), blood loss (3.5 vs 3.5 ml; p = 0.740), rate of placement of additional trocars (14.3% vs 17.9%; p = 0.657), rate of open conversion (2.6% vs 3.6%; p = 0.853), and postoperative length of hospital stay (6 vs 5 days; p = 0.237). Furthermore, obesity was not a significant risk factor for postoperative complications (postoperative bleeding, wound infection, and pneumonia). There are no significant differences in peri- and postoperative outcomes of transabdominal laparoscopic adrenalectomy in patients with obesity compared with those without obesity. Transabdominal laparoscopic adrenalectomy is feasible and safe for patients with obesity.

Impact of Body Mass Index on Surgical and Oncological Outcomes in Laparoscopic Total Mesorectal Excision for Locally Advanced Rectal Cancer after Neoadjuvant 5-Fluorouracil-Based Chemoradiotherapy

Aims

To evaluate the impact of body mass index (BMI) on the surgical outcome of laparoscopic total mesorectal excision (laTME) for locally advanced rectal cancer (LARC, clinically staged as UICC stage II/III) after neoadjuvant chemoradiotherapy (nCRT).

Methods

312 LARC patients undergoing laTME after nCRT were divided into nonobese (BMI < 25.0 kg/m², n = 249) and obese (BMI ≥ 25.0 kg/m², n = 63) groups. Preoperative radiotherapy was delivered in 45–50.4 Gy/25f, 5 days/week, and concurrent chemotherapy using FOLFOX or CapeOX. Technical feasibility, postoperative and oncological outcome were compared between groups.

Results

Obese patients had significantly longer operative time (P = 0.004). There was no significant difference regarding estimated blood loss, conversion, postoperative recovery, and morbidities. Multivariate analysis demonstrated that higher ASA score and abdominoperineal resection were risk factors for postoperative complications and diverting stoma was a protective factor. The length of resection margin, circumferential resection margin involvement, and number of lymph node retrieved were comparable. With a median follow-up time of 55 months (ranging 20–102 months), oncological outcome was comparable in terms of overall survival, local recurrence, and distant metastasis.

Conclusions

Obesity does not affect surgical or oncological outcome of laTME after nCRT. LaTME may be feasible and safe to obese LARC patients after nCRT in a specialized center.

Impact of Body Mass Index on Early Postoperative and Long-Term Outcome after Rectal Cancer Surgery

Background

The aim of this study was to investigate the impact of obesity and underweight onto early postoperative and long-term oncological outcome after surgery for rectal cancer.

Methods

Data from 2008 until 2011 was gathered by a German prospective multicenter observational study. 62 items were reported by the physicians in charge, and a consecutive follow-up was performed if the patient had signed a consent form. Patients were subclassified into: underweight, normal weight, overweight, and obese - using the definitions of the World Health Organization.

Results

In total, 9,920 patients were included, of whom 2.1% were underweight and 19.4% obese. The mean age was 68 years (range 21-99 years). Postoperative morbidity (mean 38.0%) was significantly increased in underweight and obese patients (p < 0.001). In-hospital mortality was 3.1% on average with no significant differences among patient groups (p = 0.176). The 5-year overall survival ranged between 36.9 and 61.3% and was worse in underweight and prolonged in overweight and obese patients compared to those with normal weight (p < 0.001 each). While the 5-year disease-free survival was increased in overweight and obese patients (p < 0.05 each), the 5-year local recurrence rate showed no correlation (p > 0.05 each). Multivariate analysis revealed that advanced age, higher ASA scoring, postoperative morbidity, and advanced tumor growth worsened the long-term survival independently.

Conclusions

Underweight patients had a worse early and long-term outcome after rectal cancer surgery. Overweight and obesity were associated with a significantly better long-term survival.

Meta-analysis of the clinicopathological characteristics and peri-operative outcomes of colorectal cancer in obese patients

BACKGROUND

The effect of obesity on the clinicopathological characteristics of colorectal cancer (CRC) has not been clearly characterized. This meta-analysis assesses the pathological and perioperative outcomes of obese patients undergoing surgical resection for CRC.

METHODS

Meta-analysis was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Databases were searched for studies reporting outcomes for obese and non-obese patients undergoing primary CRC resection, based on body-mass index measurement. Results were reported as mean differences or pooled odds ratios (OR) with 95% confidence intervals (95% CI).

RESULTS

A total of 2183 citations were reviewed; 29 studies comprising 56,293 patients were ultimately included in the analysis, with an obesity rate of 19.3%. Obese patients with colorectal cancer were more often female (OR 1.2, 95% CI 1.1-1.2, p<0.001) but there was no difference in the proportion of rectal cancers, T4 tumours, tumour differentiation or margin positivity. Obese patients were significantly more likely to have lymph node metastases (OR 1.2, 95% CI 1.1-1.2, p<0.001), have a lower nodal yield, were associated with a longer duration of surgery, more blood loss and conversions to open surgery (OR 2.6, 95% CI 1.6-4.0, p<0.001) but with no difference in length of stay or post-operative mortality.

CONCLUSION

This meta-analysis demonstrates that obese patients undergoing resection for CRC are more likely to have node positive disease, longer surgery and higher failure rates of minimally invasive approaches. The challenges of colorectal cancer resection in obese patients are emphasized.

[Enhanced recovery after preserving the left colonic artery during laparoscopic anterior resection for rectal cancer]

OBJECTIVE

To evaluate the postoperative outcomes of preserving the left colonic artery during laparoscopic anterior resection for rectal cancer.

METHODS

The clinicopathologic data of 91 rectal cancer patients (pathologic Stage II) undergoing laparoscopic anterior resection was retrospectively analyzed. During the surgeries, the left colonic artery was preserved in 40 patients (preserved group) and ligated in 51 patients (unpreserved group). The operating time, intraoperative blood loss, time to first flatus and defecation, duration of postoperative abdominal distension and pain, number of retrieved lymph nodes, ileum fistulation and anatomical leakage rate were compared between the two groups.

RESULTS

The surgeries were completed in all the 91 patients laparoscopically without conversion. There was no intraoperative complications including rectal perforation, injury to vessel or ureter in either group. The operating time, blood loss and number of retrieved lymph nodes were similar between the groups (P>0.05). Three patients in preserved group and 5 in ligation group received preventive ileum fistulation due to low rectal cancer. Anatomical leakage occurred in three patients of unpreserved group. The average duration of postoperative abdominal distension and pain was 2.14∓0.35 days in preserved group and 3.15∓0.42 days in ligation group. The time to first flatus and defecation was 37.15∓12.62 h and 3.16∓0.52 days in preserved group and 62.25∓11.75 h and 4.25∓0.75 days in ligation group. Postoperative hospital stay was 4.54∓0.42 days in preserved group and 6.23∓0.51 days in ligation group. Total hospitalization cost in the two groups was 34 525.32∓1206.36 Yuan and 41 215∓1051.32 Yuan, respectively. Significant differences were found the in duration of postoperative abdominal distension and pain, postoperative hospital stay, and total cost between the two groups (P<0.05).

CONCLUSION

During laparoscopic anterior resection for rectal cancer, preserving the left colonic artery effectively ensures the blood supply to the anastomosis and the remaining descending colon to promote the recovery of the patients after surgery.

Outcome of rectal cancer surgery in obese and nonobese patients: a meta-analysis

Background

The escalating global epidemic of obesity is of worldwide concern because of its association with serious negative effects on health. The technical difficulty of rectal cancer surgery is exacerbated in obese patients, which may compromise outcomes. High-quality, relevant evidence is limited. This meta-analysis aims to assess the outcomes of rectal cancer surgery in obese and nonobese patients.

Methods

The electronic databases Pubmed, Medline, Embase, Web of Science, and the Cochrane Library were used to search for articles that evaluated the outcomes of rectal cancer surgery in obese and nonobese patients. Fixed-effects and random-effects models were used to calculate the combined overall effect sizes of pooled data. Data are presented as odds ratios (OR) or weighted mean differences (WMD) with 95 % confidence intervals (CIs).

Results

Ten appropriate observational studies were identified from 290 published articles. In the obese group, conversion rates (OR 2.78; 95 % CI 1.67–4.61), overall morbidity (OR 1.36; 95 % CI 1.25–1.47), anastomotic leak (OR 3.94; 95 % CI 1.88–8.24), wound infection (OR 2.22; 95 % CI 1.47, 3.36), and pulmonary events (OR 2.10; 95 % CI 1.18, 3.74) were all significantly increased. For pathological results, no statistical differences in the number of harvested lymph nodes and the positive margin were noted between the two groups.

Conclusions

Based on a meta-analysis, obesity increases the conversion rate and postoperative morbidity of rectal cancer surgery but does not influence pathological results.

Outcome of rectal cancer surgery in obese and nonobese patients: a meta-analysis

BACKGROUND

The escalating global epidemic of obesity is of worldwide concern because of its association with serious negative effects on health. The technical difficulty of rectal cancer surgery is exacerbated in obese patients, which may compromise outcomes. High-quality, relevant evidence is limited. This meta-analysis aims to assess the outcomes of rectal cancer surgery in obese and nonobese patients.

METHODS

The electronic databases Pubmed, Medline, Embase, Web of Science, and the Cochrane Library were used to search for articles that evaluated the outcomes of rectal cancer surgery in obese and nonobese patients. Fixed-effects and random-effects models were used to calculate the combined overall effect sizes of pooled data. Data are presented as odds ratios (OR) or weighted mean differences (WMD) with 95% confidence intervals (CIs).

RESULTS

Ten appropriate observational studies were identified from 290 published articles. In the obese group, conversion rates (OR 2.78; 95% CI 1.67-4.61), overall morbidity (OR 1.36; 95% CI 1.25-1.47), anastomotic leak (OR 3.94; 95% CI 1.88-8.24), wound infection (OR 2.22; 95% CI 1.47, 3.36), and pulmonary events (OR 2.10; 95% CI 1.18, 3.74) were all significantly increased. For pathological results, no statistical differences in the number of harvested lymph nodes and the positive margin were noted between the two groups.

CONCLUSIONS

Based on a meta-analysis, obesity increases the conversion rate and postoperative morbidity of rectal cancer surgery but does not influence pathological results.

Hand-Assisted versus Straight-Laparoscopic versus Open Proctosigmoidectomy for Treatment of Sigmoid and Rectal Cancer: A Case-Matched Study of 100 Patients

To assess the efficacy of laparoscopic proctosigmoidectomy for cancer treatment, 25 patients who underwent hand-assisted laparoscopic resection during the study period (9/2006 - 7/2012) were matched to 25 straight-laparoscopic and 50 open-surgery cases. The patients who underwent hand-assisted resection had higher rates of preoperative cardiac disease and hypertension than did the straight-laparoscopy and open-surgery groups. Straight-laparoscopic surgery seems to provide faster convalescence compared with open surgery and hand-assisted laparoscopic surgery.

Obesity and Colorectal Cancer

There is strong evidence that modifiable lifestyle factors such as obesity play a key role in colorectal carcinogenesis. Epidemiologic data have consistently reported a positive association between obesity and colorectal cancer. The relative risk associated with general obesity (as assessed by BMI) is higher in men than in women and for cancer of the colon than for cancer of the rectum. Abdominal obesity (as assessed by waist circumference (WC) or waist-to-hip ratio) is associated with an increased risk of colorectal cancer in both sexes, with stronger associations for cancer of the colon than for cancer of the rectum. Plausible biological mechanisms include insulin resistance, hyperinsulinemia, chronic inflammation, altered levels of growth factors, adipocytokines and steroid hormones. In addition to its effect on colorectal cancer incidence, obesity may play a role in colorectal cancer recurrence, treatment outcomes and survival. Understanding the effects of childhood and adolescent obesity and weight change over the life course in relation to future risk of colorectal cancer is incomplete but essential for targeted preventive recommendations. This chapter summarizes the current evidence on the relationship between obesity and colorectal cancer and colorectal adenoma, a common precursor lesion.

Factors affecting sphincter-preserving resection treatment for patients with low rectal cancer

The aim of the present study was to identify the factors associated with the use of sphincter-preserving resection (SPR) surgery for the treatment of low rectal cancer. A total of 330 patients with histopathologically confirmed low rectal cancer were divided into two groups, namely the abdominoperineal resection (APR) and sphincter-preserving (SP) groups. For SPR factor analysis, the χ² test was performed as the univariate analysis, while a logistic regression test was conducted as the multivariate analysis. Of the 330 patients, 192 cases (58.18%) received SPR surgery and 138 cases (41.82%) underwent an APR. Univariate analysis results revealed that the sphincter-preserving factor was significantly associated with age, gender, ethnicity, body mass index (BMI), total infiltrated circumference, distance of the tumor from the anal verge (DTAV), depth of invasion and tumor grade (P<0.05). However, there were no statistically significant associations with family medical history, diabetes history, venous tumor embolism, growth type, tumor length, lymphatic metastasis and level of preoperative carcinoembryonic antigen (P>0.05). Multivariate analysis indicated that the sphincter-preserving factor was strongly associated with DTAV and the depth of invasion, with significant statistical difference (P<0.05). Therefore, selecting SPR surgery for patients with low rectal cancer is dependent on age, gender, ethnicity, BMI, the total infiltrated circumference, DTAV, depth of invasion and tumor grade. In addition, DTAV and the depth of invasion are independent risk factors for the selection of SPR surgery.

The impact of obesity on patient survival in liver transplant recipients: a meta-analysis

BACKGROUND & AIMS

It is controversial if obesity has an impact on overall survival after liver transplantation (LT). The goal of this study was to determine if obesity impacts liver transplant recipient survival. Through subgroup analysis, we also evaluated different body mass index (BMI) thresholds and the confounding effect of ascites on survival.

METHODS

A systematic literature search from 1990 until July 2013. The main outcome was to evaluate the impact of obesity on survival in adult LT recipients. Dochotomous outcomes were reported as relative risk (RR) with 95% confidence intervals (CI).

RESULTS

Thirteen studies with a total 2275 obese and 72 212 non obese patients were included in the analysis. The combined analysis showed no difference in mortality between control and increased weight patients (RR = 0.97, 95% CI [0.82, 1.13], P = 0.66) at last follow-up. Moreover, no differences in mortality were noted in subgroup analysis comparing different BMI thresholds. There was also no differences in survival when BMI was adjusted for ascites or in studies where the liver disease severity was similar. Obese patients had worse survival than nonobese patients in pooled analysis of studies which had similar causes of liver disease (RR = 0.69, 95% CI [0.52, 0.92], P = 0.01).

CONCLUSION

The results of our pools analysis suggest that BMI does not specifically impact patient survival. However, obese patients have worse survival when analysis was performed in studies whose cohorts of obese and nonobese patients had similar causes of liver disease.

Pre-operative granulocyte/lymphocyte ratio as a predictive marker of post-operative complications in patients with colorectal cancer

The aim of the present study was to assess the clinical relevance of the pre-operative granulocyte/lymphocyte (G/L) ratio as a predictive marker of post-operative complications in patients with colorectal cancer. In total, 85 patients (59 males and 26 females; mean age, 68.9 years) underwent surgery for colorectal cancer at the Department of Surgery, Ibraki Medical Center, Tokyo Medical University (Ami, Japan), and were divided into post-operative complication and non-complication groups. Clinical data, including age, gender, body mass index, tumor localization, tumor pathological type, cancer staging, surgery time, volume of surgical bleeding, pre-operative G/L ratio and further pre-operative laboratory data, including levels of albumin and C-reactive protein, Glasgow Prognostic Score, white blood cell count and levels of hemoglobin, creatine kinase, lactate dehydrogenase, carcinoembryonic antigen and carbohydrate antigen 19-9 were analyzed between these groups. The total post-operative complication rate was 18.8%. On univariate analysis, the amount of surgical bleeding and the pre-operative G/L ratio were significantly higher in the complication group than in the non-complication group (299.8±361.7 vs. 155.6±268.6 ml, P<0.05; and 6.73±10.38 vs. 3.49±2.78, P<0.05, respectively). Multivariate logistic regression analysis for the risk factors of post-operative complications, determined using univariate analysis, demonstrated that the amount of surgical bleeding and the pre-operative G/L ratio were independent risk factors of post-operative complications in patients with colorectal cancer. In conclusion, the G/L ratio may be a clinically relevant pre-operative predictive marker for post-operative complications.

Impact of obesity on complications after resection for rectal cancer

AIM

The prevalence of obesity in Australia is high and increasing, with associated serious negative effects on health. The technical complexity of rectal cancer surgery is exacerbated in obese patients, which may compromise outcomes. The aim of this study was to examine the association between obesity and complications after resection of rectal cancer.

METHOD

Data were drawn from a comprehensive prospective registry of rectal cancer resections performed from 2007 to 2011 by members of the colorectal surgical unit in a tertiary referral hospital and in a single private hospital with which they were affiliated.

RESULTS

Of 255 patients who had a resection for rectal cancer during the study period, 95 (37%) were classified as obese on the basis of a body mass index (BMI) ≥ 30 kg/m(2) . Among 24 postoperative complications the only significant differences for obese patients were higher rates of wound complications (16% vs 8%, P = 0.038), small bowel obstruction (4% vs 0%, P = 0.019) and prolonged ileus (18% vs 8%, P = 0.011). The total number of complications did not differ significantly between obese and nonobese patients, and there was no difference between obese and nonobese patients in the rates of reoperation and postoperative death.

CONCLUSION

This study did not support an association between obesity and early postoperative complications after resection of rectal cancer.

Association of obesity and overweight with overall survival in colorectal cancer patients: a meta-analysis of 29 studies

PURPOSE

Previous studies that assessed the relationship between obesity, overweight, and survival in colorectal cancer (CRC) have provided conflicting results. Therefore, we quantitatively summarized existing evidence to estimate the association between obesity/overweight and overall survival (OS) in CRC patients and explored potentially important sources of variability.

METHODS

Eligible studies were identified via PubMed and EMBASE searches. The summary hazard ratio (sHR) was estimated using a fixed-effects or random-effects model according to the heterogeneity between the studies. Meta-regression and subgroup analyses were performed to explore potential sources of heterogeneity.

RESULTS

A total of 29 eligible studies, with 51,303 CRC patients, were finally included. The overall analysis showed worse OS among obese patients [sHR 1.10, 95 % confidence intervals (CI) 1.06-1.15], but not among overweight patients (sHR 0.92, 95 % CI 0.86-1.00), than in normal-weight patients. Considerable heterogeneity was observed across studies, which was primarily attributed to the timing of body mass index (BMI) assessment (meta-regression p < 0.05). The association between obesity and worse OS was strengthened when BMI was assessed before diagnosis (sHR 1.30, 95 % CI, 1.17-1.44). Conversely, post-diagnostic, in particular post-treatment, overweight was associated with a better OS (sHR 0.79, 95 % CI 0.70-0.91). Other factors, including gender, geographic location, and stage, may also modify the prognostic value of obesity or overweight.

CONCLUSIONS

Obese but not overweight patients appear to have worse OS than normal-weight patients with CRC. The associations of obesity and overweight with OS in CRC patients majorly depend upon the timing of BMI assessment.

Impact of BMI on postoperative outcomes in patients undergoing proctectomy for rectal cancer: a national surgical quality improvement program analysis

BACKGROUND

There is a mounting body of evidence that suggests worsened postoperative outcomes at the extremes of BMI, yet few studies investigate this relationship in patients undergoing proctectomy for rectal cancer.

OBJECTIVE

We aimed to examine the relationship between BMI and short-term outcomes after proctectomy for cancer.

DESIGN

This was a retrospective study comparing the outcomes of patients undergoing proctectomy for rectal cancer as they relate to BMI.

SETTINGS

The American College of Surgeons-National Surgical Quality Improvement Program database was queried for this study.

PATIENTS

Patients included were those who underwent proctectomy for rectal neoplasm between 2005 and 2011.

MAIN OUTCOME MEASURES

Study end points included 30-day mortality and overall morbidity, including the receipt of blood transfusion, venous thromboembolic disease, wound dehiscence, renal failure, reintubation, cardiac complications, readmission, reoperation, and infectious complications (surgical site infection, intra-abdominal abscess, pneumonia, and urinary tract infection). Univariate logistic regression was used to analyze differences among patients of varying BMI ranges (kg/m; ≤20, 20-24, 25-29, 30-34, and ≥35). When significant differences were found, multivariable logistic regression, adjusting for preoperative demographic and clinical variables, was performed.

RESULTS

A total of 11,995 patients were analyzed in this study. The incidences of overall morbidity, wound infection, urinary tract infection, venous thromboembolic event, and sepsis were highest in those patients with a BMI of ≥35 kg/m (OR, 1.63, 3.42, 1.47, 1.64, and 1.50). Wound dehiscence was also significantly more common in heavier patients. Patients with a BMI <20 kg/m had significantly increased rates of mortality (OR, 1.72) and sepsis (OR, 1.30).

LIMITATIONS

This study was limited by its retrospective design. Furthermore, it only includes patients from the American College of Surgeons-National Surgical Quality Improvement Program database, limiting its generalizability to nonparticipating hospitals.

CONCLUSIONS

Obese and underweight patients undergoing proctectomy for neoplasm are at a higher risk for postoperative complications and death.

Effect of BMI on outcomes in proctectomy

BACKGROUND

The unique surgical challenges of proctectomy may be amplified in obese patients. We examined surgical outcomes of a large, diverse sample of obese patients undergoing proctectomy.

OBJECTIVE

The purpose of this work was to determine whether increased BMI is associated with increased complications in proctectomy.

DESIGN

This was a retrospective review.

SETTINGS

The study uses the American College of Surgeons National Surgical Quality Improvement Program database (2010 and 2011).

PATIENTS

Patients included were those undergoing nonemergent proctectomy, excluding rectal prolapse cases. Patients were grouped by BMI using the World Health Organization classifications of underweight (BMI <18.5); normal (18.5-24.9); overweight (25.0-29.9); and class I (30.0-34.9), class II (35.0-39.9), and class III (≥40.0) obesity.

MAIN OUTCOME MEASURES

We analyzed the effect of preoperative and intraoperative factors on 30-day outcomes. Continuous variables were compared with Wilcoxon rank-sum tests and proportions with the Fisher exact or χ tests. Logistic regression controlled for the effects of multiple risk factors.

RESULTS

Among 5570 patients, class I, II, and III obesity were significantly associated with higher rates of overall complications (44.0%, 50.8%, and 46.6% vs 38.1% for normal-weight patients; p < 0.05). Superficial wound infection was significantly higher in classes I, II, and III (11.6%, 17.8%, and 13.0% vs 8.0% for normal-weight patients; p < 0.05). Operative times for patients in all obesity classes were significantly longer than for normal-weight patients. On multivariate analysis, an obese BMI independently predicted complications; ORs (95% CIs) were 1.36 (1.14-1.62) for class I obesity, 1.99 (1.54-2.54) for class II, and 1.42 (1.02-1.96) for class III.

LIMITATIONS

This study was a retrospective design with limited follow-up.

CONCLUSIONS

Class I, II, and III obese patients were at significantly increased risk for morbidity compared with normal BMI patients. Class II obese patients had the highest rate of complications, a finding that deserves further investigation.

Long term outcomes of neuroendocrine carcinomas (high-grade neuroendocrine tumors) of the colon, rectum, and anal canal

INTRODUCTION AND AIM

Neuroendocrine carcinomas (NEC) of the large intestine are rare and aggressive neoplasms. This study was designed to review the experience at a single institution and analyze the outcomes to improve our understanding of these tumors.

METHODS

The patients with NEC (high-grade neuroendocrine tumor) of the colon, rectum, and anal canal were identified from June 1993 to April 2011. Clinical features studied were patient demographics, presenting symptoms, tumor location, tumor stage, treatment status and length of follow-up.

RESULTS

Twenty-five patients were identified. Stages of the diseases were I (n=5), II (n=1), III (n=10) and IV (n=9). Locations of the tumors were: colon (36%); rectum (28%) and anal canal (36%). Rectal bleeding (36%) and pain (32%) were the most common symptoms but 16% of patients were asymptomatic. Among the patients with local or locally advanced disease, only five patients had surgery alone. The remainder of the patients underwent chemotherapy with/without radiation. Mean follow-up was 33.7 ± 8.4 months after diagnosis. NEC of the large bowel and anal canal has very distinctive pathologic features and a very poor prognosis. More than one third of the patients with NEC had metastatic disease at the time of diagnosis. When these tumors are in an advanced stage none of the treatment modalities impact on survival.

CONCLUSION

The present study showed the poor prognosis of these rare tumors.

Anus-preserving rectectomy via telescopic colorectal mucosal anastomosis for low rectal cancer: Experience from a Chinese cohort

AIM: To investigate the safety and efficacy of anus-preserving rectectomy via telescopic colorectal mucosal anastomosis (TCMA) for low rectal cancer.

METHODS: From August 1993 to October 2012, 420 patients including 253 males and 167 females with low rectal cancer underwent transabdominal and transanal anterior resection, followed by TCMA. The distance between the anus and inferior margin of the tumor ranged from 5 to 7 cm, and was 5 cm in 6 patients, 6 cm in 127, and 7 cm in 287 patients. Tumor-node-metastasis staging showed that 136 patients had stage I, 252 had stage II and 32 had stage III. Fifty-six patients with T3 or over received preoperative neoadjuvant chemoradiotherapy.

RESULTS: The postoperative follow-up rate was 91.9% (386/420) with a median time of 6.4 years. All 420 patients underwent radical resection. No postoperative death occurred. Postoperative complications included anastomotic leakage in 13 (3.1%) patients and anastomotic stenosis in 7 (1.6%). The local recurrence rate after surgery was 6.2%, the hepatic metastasis rate was 13.2% and the pulmonary metastasis rate was 2.3%. The 5-year survival rate was 74.0% and the disease-free survival rate was 71.0%. Kirwan classification showed that continence was good in 94.4% of patients with stage I when scored 12 mo after resection.

CONCLUSION: TCMA for patients with low rectal cancer leads to better quality of life and satisfactory defecation function, and lowers anastomotic leakage occurrence, and might be one of the safe operative procedures in anus-preserving rectectomy.