The impact of visceral obesity on surgical outcomes of laparoscopic surgery for colon cancer

Effect of preoperative asymptomatic renal dysfunction on the clinical course after colectomy for colon cancer

PURPOSE

To evaluate the effect of mild renal dysfunction on the clinical course after colectomy in patients with colon cancer.

METHODS

The subjects of this retrospective study were 263 patients who underwent surgical resection for colon cancer at our hospital between 2011 and 2015. Renal function was assessed based on preoperative estimated glomerular filtration rate (eGFR) values. Patients were divided into groups based on their eGFR value of 55 ml/min/1.73 m². The Mann-Whitney U test, chi-square or Fisher exact test, and log-rank test were used in the data analysis.

RESULTS

There were 59 patients (22.4%) in the low eGFR group and 204 patients in the normal eGFR group. There were differences between the groups in age, comorbidities, and the levels of hemoglobin, albumin, and serum creatinine. The overall postoperative complication rate, frequency of severe complications, and length of stay were significantly higher in the low eGFR group than in the normal eGFR group. Multivariate analysis revealed that low eGFR was the only independent risk factor for severe complications (Clavien-Dindo classification III/IV). There were no differences in survival between the groups.

CONCLUSION

Preoperative asymptomatic renal dysfunction may be correlated with the development of postoperative complications and a possible significant risk factor for severe complications after colon cancer surgery.

Body Composition, Inflammation, and 5-Year Outcomes in Colon Cancer

IMPORTANCE

Obesity, particularly visceral obesity and sarcopenia, are poor prognostic indicators in colon cancer.

OBJECTIVES

To explore the association between body composition profiles and 5-year colon cancer outcomes and delineate the associated underlying inflammatory processes.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter translational cohort study included patients with nonmetastatic colon cancer who did not have underlying chronic inflammatory disorders and were not receiving anti-inflammatory drugs referred to tertiary cancer centers from 2009 to 2015. Preoperative acute phase proteins (white cell count, C-reactive protein, and albumin), cytokines (interleukin [IL]-1b, IL-2, IL-6, IL-10, interferon γ, and tumor necrosis factor α), vascular endothelial growth factor (VEGF), and cell surface receptor expression levels (CD11b and CD14) were measured. All patients underwent follow-up for at least 5 years. Data were analyzed in December 2020.

EXPOSURE

Nonmetastatic colon cancer.

MAIN OUTCOMES AND MEASURES

The associations of body composition profiles with 5-year cancer recurrence and disease-specific mortality were analyzed using Mantel Cox log-rank test and Kaplan-Meier curves.

RESULTS

A total of 28 patients were included (median [interquartile range] age, 67 [58-72] years; 22 [78.6%] men). Low skeletal muscle area (SMA) and high visceral to total fat ratio were associated with poor clinical and oncological outcomes, including increased 5-year recurrence (low SMA: hazard ratio [HR], 2.30 [95% CI, 1.41-2.89]; P = .04; high visceral to total fat ratio: HR, 5.78 [95% CI, 3.66-7.95]; P = .02). High visceral to total fat ratio was associated with increased 5-year disease-specific mortality (HR, 5.92 [95% CI, 4.04-8.00]; P = .02). Patients with low SMA who developed a cancer recurrence, compared with those who did not, had higher C-reactive protein (mean [SD], 31.24 [6.95] mg/dL vs 8.11 [0.58] mg/dL; P = .003), IL-6 (mean [SD], 1.93 [1.16] ng/mL vs 0.88 [0.14] ng/mL; P = .004), VEGF (mean [SD], 310.03 [122.66] ng/mL vs 176.12 [22.94] ng/mL; P = .007), and CD14 (mean [SD], 521.23 [302.02] ng/mL vs 322.07 [98.35] ng/mL; P = .03) expression and lower albumin (mean [SD], 3.8 [0.6] g/dL vs 43.50 [3.69] g/dL; P = .01), IL-2 (mean [SD], 0.45 [0.25] ng/mL vs 0.94 [0.43] ng/mL; P < .001), IL-10 (mean [SD], 8.15 [1.09] ng/mL vs 16.32 [4.43] ng/mL; P = .004), and interferon γ (mean [SD], 2.61 [1.36] ng/mL vs 14.87 [3.43] ng/mL; P = .02) levels. Patients with high visceral to total fat ratio who developed recurrence had higher levels of IL-6 (mean [SD], 5.26 [7.05] ng/mL vs 2.76 [3.11] ng/mL; P = .03) and tumor necrosis factor α (mean [SD], 5.74 [4.53] ng/mL vs 4.50 [1.99] ng/mL; P = .03).

CONCLUSIONS AND RELEVANCE

These findings suggest that low SMA and high visceral to total fat ratio were associated with worse colon cancer outcomes and with increased expression of proinflammatory cytokines and VEGF and inhibition of anti-inflammatory cytokines.

Laparoscopic vs. Open Surgery for Stage II/III Colon Cancer Patients With Body Mass Index >25 kg/m2

AIM

To compare long- and short-term outcomes of laparoscopic surgery with those of open surgery for patients with colorectal cancer and body mass index over 25 kg/m² Patients and Methods: This multicentre, retrospective study analysed clinical records and identified 178 patients with body mass index over 25 kg/m² who underwent surgery for colon and rectosigmoid cancer between 2000 and 2016. After applying propensity score matching, 96 patients were finally included. The primary outcome was the 3-year recurrence-free survival rate, and the secondary outcomes were short-term results during and after surgery.

RESULTS

The 3-year recurrence-free survival rates were similar for the laparoscopic and open surgery groups. The laparoscopic surgery group had longer operative times but less blood loss and shorter periods of hospital stay. There were no differences in incidence of postoperative complications.

CONCLUSION

Laparoscopic and open surgeries had similar long-term outcomes for obese patients. Laparoscopic surgery is an effective option for this population.

The Role of Visceral Obesity, Sarcopenia and Sarcopenic Obesity on Surgical Outcomes After Liver Resections for Colorectal Metastases

Background

The impact of body compositions on surgical results is controversially discussed. This study examined whether visceral obesity, sarcopenia or sarcopenic obesity influence the outcome after hepatic resections of synchronous colorectal liver metastases.

Methods

Ninety-four consecutive patients with primary hepatic resections of synchronous colorectal metastases were identified from a single center database between January 2013 and August 2018. Patient characteristics and 30-day morbidity were retrospectively analyzed. Body fat and skeletal muscle were calculated by planimetry from single-slice CT images at the level of L3.

Results

Fifty-nine patients (62.8%) underwent minor hepatectomies, and 35 patients underwent major resections (37.2%). Postoperative complications occurred in 60 patients (62.8%) including 35 patients with major complications (Clavien–Dindo grade III–V). The mortality was nil at 30 days and 2.1% at 90 days. The body mass index showed no influence on postoperative outcomes (p = 1.0). Visceral obesity was found in 66 patients (70.2%) and was significantly associated with overall and major complication rates (p = .002, p = .012, respectively). Sarcopenia was observed in 34 patients (36.2%) without a significant impact on morbidity (p = .461), however, with longer hospital stay. Sarcopenic obesity was found in 18 patients (19.1%) and was significantly associated with postoperative complications (p = .014). Visceral obesity, sarcopenia and sarcopenic obesity were all identified as significant risk factors for overall postoperative complications.

Conclusion

Visceral obesity, sarcopenic obesity and sarcopenia are independent risk factors for overall complications after resections of CRLM. Early recognition of extremes in body compositions could prompt to perioperative interventions and thus improve postoperative outcomes.

Laparoscopic gastrectomy reduces adverse postoperative outcomes and decreases morbidity for gastric cancer patients with visceral obesity: a propensity score-matched analysis

Background: Laparoscopic gastrectomy for gastric cancer shortens the recovery period without decreasing long-term survival. However, clinical evidence on whether laparoscopic radical gastrectomy reduces the surgical stress and improves the short- and long-term outcomes of obese patients with gastric cancer is lacking. We compared the short- and long-term outcomes of gastric cancer patients with visceral obesity (VO) who underwent laparoscopic gastrectomy (LG) or open gastrectomy (OG).

Methods: We prospectively collected data from 578 patients who underwent radical gastrectomy in two centers between January 2014 and December 2016. The visceral fat area (VFA) was measured on the umbilicus level, and VFA ≥100 cm² was defined as VO. The section bias was reduced by conducting a propensity score matching analysis. The short- and long-term outcomes were further compared between patients who underwent OG and those who underwent LG.

Results: Overall, 245 patients (42.61%) were classified as having VO, of whom 102 were included for further analysis after matching. There were no significant differences in clinical characteristics between the two groups in the matched cohort. The LG group had significantly fewer overall complications (P<0.001) and shorter postoperative hospital stays (P<0.001). Subgroup analysis of postoperative complications also showed that the incidence of surgical complications was lower in the LG group (P=0.002). Further survival analysis showed the LG group had significantly better long-term overall survival (P=0.017).

Conclusions: Compared with open radical gastrectomy, laparoscopy would reduce the rate of postoperative complications in patients with VO, as well as prolong their overall survival.

Visceral Fat and Anastomotic Leakage After Colon Cancer Resection

BACKGROUND

Visceral fat is considered a risk for postoperative complications in colon cancer surgery. However, the association with anastomotic leakage as the most worrisome complication is not clear mainly because of underpowered studies.

OBJECTIVE

The purpose of this study was to analyze the effect of visceral fat as a continuous variable on anastomotic leakage in a large cohort of colon cancer resections.

DESIGN

This was a retrospective, multicenter cohort study.

SETTINGS

This study used data of the Dutch Surgical Colorectal Audit of the years 2011 through 2014 from 8 Dutch teaching hospitals. Visceral fat was assessed on the routine preoperative abdominal CT scan.

PATIENTS

A total of 2370 patients underwent colon cancer resection with primary anastomosis. There were 2011 patients operated electively and 359 in an emergency setting.

MAIN OUTCOME MEASURES

The effect of visceral fat on anastomotic leakage after multivariable analysis was measured.

RESULTS

Visceral fat was associated with anastomotic leakage in the elective colon resection group (n = 2011) but not in emergency colon resections (n = 359). Significant confounding was found for type of resection, BMI, and sex. The association of male sex and BMI as previously reported risk factors for anastomotic leakage was explained by visceral fat.

LIMITATIONS

The study was limited by its retrospective character and missing clinical data of known risk factors for anastomotic leakage, like smoking history and certain medication.

CONCLUSIONS

The independent association of visceral fat with anastomotic leakage was confined to the elective colon cancer resection group. The previously reported associations of male sex and BMI with anastomotic leakage were explained by visceral fat. Visceral fat-associated comorbidities did not influence anastomotic leakage, suggesting that its effect on colon anastomotic healing is local rather than systemic. Future risk analysis for anastomotic leakage in colon cancer surgery should contain visceral fat values and consider subgroup differences. See Video Abstract at http://links.lww.com/DCR/B396.

ADIPOSIDAD VISCERAL Y FUGA ANASTOMTICA EN CASOS DE RESECCIN DE CNCER DE COLON

ANTECEDENTES:La acumulación de grasa visceral se considera como un factor de riesgo en caso de complicaciones postoperatorias de cirugía de cáncer de colon. Sin embargo, la asociación con la fuga anastomótica como la complicación más preocupante no está clara principalmente debido a los estudios de bajo impacto disponibles.OBJETIVO:Analizar el efecto de la adiposidad visceral como una variable contínua sobre la fuga anastomótica en una gran cohorte de resecciones de cáncer de colon.DISEÑO:Estudio de cohorte multicéntrico retrospectivo.AJUSTES:Se utilizaron los datos de la Auditoría Colorrectal Quirúrgica Holandesa entre los años 2011 y 2014 en 8 hospitales de enseñanza de los Paises bajos. La grasa visceral fué evaluada por medio de la tomografía computada abdominal preoperatoria de rutina.PACIENTES:Un total de 2370 pacientes fueron sometidos a resección de cáncer de colon con anastomosis primaria. 2011 pacientes fueron operados electivamente y 359 en situación de emergencia.PRINCIPALES MEDIDAS DE RESULTADO:El efecto de la adiposidad visceral en la fuga anastomótica después del análisis multivariable.RESULTADOS:La grasa visceral se asoció con la fuga anastomótica en el grupo de resección electiva de colon (n = 2011) pero no en las resecciones de emergencia (n = 359). Se encontraron factores de confusión significativos para el tipo de resección, el índice de masa corporal y el género. La adiposidad visceral explica la asociación del género masculino y el índice de masa corporal como factores de riesgo reportados previamente en los casos de fugas anastomóticas.LIMITACIONES:Carácter retrospectivo del estudio y la falta de datos clínicos de factores de riesgo conocidos para la fuga anastomótica, como los antecedentes de tabaquismo y el consumo de ciertos medicamentos.CONCLUSIONES:La asociación independiente de la adiposidad visceral con la fuga anastomótica se limitó al grupo de resección electiva por cáncer de colon. Las asociaciones previamente reportadas de género masculino e índice de masa corporal con fuga anastomótica se explicaron por la grasa visceral. Las comorbilidades asociadas a la grasa visceral no influyeron en la fuga anastomótica, lo que sugiere que la cicatrisación anastomótica obedece más a un factor local que a un factor sistémico. Un análisis de riesgos previsibles para fugas anastomóticas en casos de resección de cáncer de colon deben involucrar los valores de la adiposidad visceral y considerar las diferencias entre subgrupos. Consulte Video Resumen en http://links.lww.com/DCR/B396. (Traducción-Dr Xavier Delgadillo).

Perirenal Fat Surface Area and Oncologic Outcome in Elective Colon Cancer Surgery

BACKGROUND

Central obesity is associated with surgical difficulties, but few studies explore the relationship with long-term results after colon cancer surgery.

OBJECTIVE

The purpose of this study was to investigate the association between perirenal fat surface area, a proxy for total visceral fat, and oncologic outcome after intestinal resection for colon cancer.

DESIGN

We investigated the association between perirenal fat surface area (exposure) on recurrence and death (outcome) in patients undergoing surgery with curative intent for colon cancer.

SETTINGS

The study was conducted at Stockholm South General Hospital, serving a population of 600,000.

PATIENTS

Patients (N = 733) without metastases at diagnosis who had a preoperative CT and had undergone elective colon resection between 2006 and 2016 were included.

MAIN OUTCOME MEASURES

We compared overall survival, recurrence-free survival, and cause-specific survival by perirenal fat surface area.

RESULTS

Patients with high perirenal fat surface area (fourth quartile) had more often left-sided tumors (45% vs 32% in the first quartile) and experienced more postoperative complications (29% vs 13%), but there were no differences in pathologic T and N stage, radicality of surgery, or adjuvant chemotherapy treatment. Overall survival decreased by increasing cancer stage but was not different between perirenal fat surface area categories. The HR for recurrence-free survival per centimeter squared increase in perirenal fat surface area was 1.00 (95% CI, 0.99-1.01) adjusted for age, sex, ASA category, tumor location, and postoperative complication Clavien-Dindo ≥2. The cumulative incidence of recurrence with death as a competing risk was not statistically different between perirenal fat surface area categories (p = 0.06). Subgroup analyses showed a nonsignificant tendency for men with low perirenal fat surface area to have a lower risk of recurrence and women a higher risk.

LIMITATIONS

In all register-based studies there can be randomly distributed errors. The results can only be generalized to colon resections. Our cohort ranged over a large year span.

CONCLUSIONS

We found no association between perirenal fat surface area and overall survival, recurrence-free survival, or cause-specific cumulative incidence of recurrence in patients undergoing colon resection for cancer. See Video Abstract at http://links.lww.com/DCR/B326.

LA SUPERFICIE DE GRASA PERIRRENAL Y EL RESULTADO ONCOLGICO EN CIRUGA ELECTIVA DE CNCER DE COLON

ANTECEDENTES:La obesidad central está asociada con dificultades quirúrgicas, pero pocos estudios exploran la relación de los resultados a largo plazo después de cirugía de cáncer de colon.OBJETIVO:Investigar la asociación entre la superficie de la grasa perirrenal, como un indicador de la grasa visceral total y el resultado oncológico después de una resección intestinal por cáncer de colon.DISEÑO:Se estudió la asociación entre el área de la superficie de la grasa perirrenal (expuesta) con la recurrencia y la muerte (resultado) de pacientes sometidos a cirugía con intención curativa por cáncer de colon.AJUSTES:Atención brindada por el Hospital General del Sur de Estocolmo a una población de 600,000 habitantes.PACIENTES:Aquellos pacientes sin metástasis (n = 733) en el momento del diagnóstico que tuvieron una tomografía computada preoperatoria y que se sometieron a una resección electiva de colon entre 2006-2016.PRINCIPALES MEDIDAS DE RESULTADO:Comparamos la sobrevida general, la sobrevida libre de recurrencia y la sobrevida específica de la causa, por área de superficie de grasa perirrenal.RESULTADOS:Los pacientes con una mayor área de superficie de grasa perirrenal (cuarto cuartil) tuvieron más frecuentemente tumores del lado izquierdo (45% frente a 32% en el primer cuartil) y sufrieron más complicaciones postoperatorias (29% frente a 13%), pero no hubieron diferencias en el Estadío patológico T y N, ni en lo radical de la cirugía o del tratamiento de quimioterapia adyuvante. La supervivencia general disminuyó al aumentar el estadio del cáncer, pero no fue diferente entre las categorías de área de superficie grasa perirrenal. La razón de riesgo para la sobrevida libre de recurrencia por aumento de cm2 en el área de la superficie grasa perirrenal fue de 1.00 (intervalo de confianza del 95%: 0.99-1.01) ajustada por edad, sexo, categoría de la Sociedad Americana de Anestesiólogos, ubicación del tumor y complicación postoperatoria según Clavien-Dindo ≥ 2) La incidencia acumulada de recurrencia con muerte como un riesgo competitivo no fue estadísticamente diferente entre las categorías de área de superficie grasa perirrenal (p = 0.06). Los análisis de subgrupos mostraron una tendencia no significativa para que los hombres con un área de superficie menor en grasa perirrenal tengan un menor riesgo de recurrencia y las mujeres un mayor riesgo.LIMITACIONES:En todos los estudios basados en registros puede haber errores distribuidos aleatoriamente. Los resultados solo pueden generalizarse a resecciones de colon. Nuestra cohorte osciló durante un gran lapso de años.CONCLUSIONES:No se encontró asociación entre el área de superficie de la grasa perirrenal y la sobrevida general, ni con la sobrevida libre de recurrencia o la incidencia acumulada de recurrencia específica de la causa en pacientes sometidos a resección de colon por cáncer. Consulte Video Resumen en http://links.lww.com/DCR/B326. (Traducción-Dr Xavier Delgadillo).

Robotic rectal cancer surgery: comparative study of the impact of obesity on early outcomes

The aim of this study was to compare the outcomes of robotic total mesorectal excision (TME) in obese versus non-obese patients. A total of 533 patients, of whom 161 were obese (30·2 per cent) underwent robotic proctectomy during the study interval. Patient obesity was not associated with adverse short-term clinical outcomes after robotic rectal cancer surgery. Indicated in the obese perhaps?

Obese patients and robotic colorectal surgery: systematic review and meta-analysis

BACKGROUND

Obesity is a major health problem, demonstrated to double the risk of colorectal cancer. The benefits of robotic colorectal surgery in obese patients remain largely unknown. This meta-analysis evaluated the clinical and pathological outcomes of robotic colorectal surgery in obese and non-obese patients.

METHODS

MEDLINE, Embase, Global Health, Healthcare Management Information Consortium (HMIC) and Midwives Information and Resources Service (MIDIRS) databases were searched on 1 August 2018 with no language restriction. Meta-analysis was performed according to PRISMA guidelines. Obese patients (BMI 30 kg/m2 or above) undergoing robotic colorectal cancer resections were compared with non-obese patients. Included outcome measures were: operative outcomes (duration of surgery, conversion to laparotomy, blood loss), postoperative complications, hospital length of stay and pathological outcomes (number of retrieved lymph nodes, positive circumferential resection margins and length of distal margin in rectal surgery).

RESULTS

A total of 131 full-text articles were reviewed, of which 12 met the inclusion criteria and were included in the final analysis. There were 3166 non-obese and 1420 obese patients. A longer duration of surgery was documented in obese compared with non-obese patients (weighted mean difference -21·99 (95 per cent c.i. -31·52 to -12·46) min; P < 0·001). Obese patients had a higher rate of conversion to laparotomy than non-obese patients (odds ratio 1·99, 95 per cent c.i. 1·54 to 2·56; P < 0·001). Blood loss, postoperative complications, length of hospital stay and pathological outcomes were not significantly different in obese and non-obese patients.

CONCLUSION

Robotic surgery in obese patients results in a significantly longer duration of surgery and higher conversion rates than in non-obese patients. Further studies should focus on better stratification of the obese population with colorectal disease as candidates for robotic procedures.

Association between specific presurgical anthropometric indexes and morbidity in patients undergoing rectal cancer resection

OBJECTIVES

Baseline body composition has been associated with dismal outcomes in patients undergoing a variety of major abdominal operations. Whether specific anthropometric indexes can predict morbidity after rectal resection has been poorly investigated. The aims of this study were to assess whether there is a relationship between body mass index and the different computed tomography-assessed body composition indexes, and whether the analysis of different body compartments could be predictive of short-term outcomes in patients undergoing curative surgery for rectal cancer.

METHODS

Computed tomography-derived measures of skeletal muscle and adipose tissue areas of patients undergoing surgery for rectal cancer between January 2009 and December 2016 were used to calculate population-specific thresholds of sarcopenia, subcutaneous adiposity, visceral adiposity, visceral obesity, sarcopenic obesity, and myosteatosis. Association between the aforementioned body composition features were related with overall complication, infection, and anastomotic leak.

RESULTS

During the study period, 311 patients received surgery and 173 were eligible for an accessible preoperative computed tomography imaging. After surgery, 59 (34.1%) patients experienced a complication, 29 an infection, and 10 an anastomotic failure. The overall morbidity rate was observed more frequently in patients with sarcopenia than in those without sarcopenia (39% versus 17.5%; P = 0.002) and infections (41.4% versus 21.5% respectively; P = 0.024). The presence of myosteatosis also was associated with a higher incidence of overall morbidity (33.9% versus 20.2% in patients without myoteatosis; P = 0.048). Anastomotic failure occurred in 6 of 10 patients with visceral obesity and in 24 of 112 (21.4%) patients without this condition (P = 0.007).

CONCLUSIONS

Some anthropometric indexes are accurate predictors of specific types of morbidity. These findings may allow a more accurate preoperative risk stratification.

Visceral Fat Area (VFA) Superior to BMI for Predicting Postoperative Complications After Radical Gastrectomy: a Prospective Cohort Study

BACKGROUND

Obesity may impact surgical outcomes of gastrectomy. Whether visceral fat area (VFA) is a better obesity parameter than body mass index (BMI) is still controversial. The aim of this study is to compare the accuracy and effectiveness of VFA and BMI in predicting the short-term surgical outcomes of gastrectomy.

METHODS

Patients who were diagnosed with gastric cancer were measured for BMI and VFA preoperatively and then divided into a VFA-H (VFA-high) group and VFA-L (VFA-low) group, at the cutoff point of 100 cm2, and a BMI-H (BMI-high) group and BMI-L (BMI-low) group, at the cutoff point of 25 kg/m2. The short-term surgical outcomes were compared between the different groups.

RESULTS

In total, 276 patients were enrolled in this study; 55 (19.9%) patients were classified into the BMI-H group, and 122 (44.2%) patients were classified into the VFA-H group. There was a significant correlation between BMI and VFA (r = 0.652, p < 0.001). Compared with the VFA-L group, the VFA-H group had a higher incidence of postoperative complications (31.1% vs. 13.0%; p < 0.001), longer operation duration (270.0 (235.0-305.0) vs. 255.0 (223.8-295.0), p = 0.046), and more blood loss (100.0 (100.0-150.0) vs. 80.0 (80.0-100.0), p < 0.001), while the BMI-H group had more blood loss than the BMI-L group (100.0 (100.0-120.0) vs. 100.0(80.0-100.0), p = 0.006). Logistic regression showed that VFA was an independent risk factor for postoperative complications (odds ratio 2.813, 95% CI 1.523-5.194; p = 0.001).

CONCLUSION

For gastric cancer patients, VFA is superior to BMI in accurately and effectively illuminating the impact of obesity on short-term surgical outcomes.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT02800005.

Impact of visceral obesity and sarcobesity on surgical outcomes and recovery after laparoscopic resection for colorectal cancer

BACKGROUND & AIMS

Studies analyzing the impact of visceral fat excess on surgical outcomes after resection for colorectal cancer (CRC) have yielded conflicting results. Visceral obesity (VO) and sarcobesity (SO) have been recently addressed as risk factors for poor short-term results while no data are available for recovery goals after surgery. No data are available on the protective effect of ERAS in VO and SO patients. The aim of this study was to assess clinical implications of computed tomography (CT) assessed VO and SO on surgical and recovery outcomes after minimally invasive resection for CRC before and after ERAS protocol implementation.

METHODS

Visceral adipose tissue (VAT) and skeletal muscle area (SMA) were retrospectively assessed using pre-operative CT studies of 261 patients who underwent laparoscopic resection for CRC between January 2012 and April 2019; ERAS protocol was adopted in 160 patients operated on after March 2014. Patients' surgical and recovery outcomes were compared according to BMI categories, VO and SO which was defined using the VAT/SMA ratio (Sarcobesity Index). Predictive factors for poor surgical and recovery outcomes were evaluated by univariate and multivariate analyses.

RESULTS

Of the 261 patients, 12.6% were BMI obese while 68.6% presented visceral obesity. BMI was not associated to any of the outcomes considered. No differences in intra-operative results were found except for a lower number of retrieved lymph nodes both in VO and SO patients. While VO showed no impact on post-operative course, SO resulted an independent risk factor for cardiac complications and prolonged post-operative ileus (PPOI) at logistic regression analysis. Furthermore, sarcobese patients showed delayed recovery after surgery. Patients enrolled in the ERAS protocol showed improved recovery outcomes for both VO and SO groups, although ERAS did not result to be a protective factor for cardiac complications and PPOI.

CONCLUSIONS

A high Sarcobesity Index is a risk factor for developing cardiac complications and PPOI after laparoscopic resection for CRC. A reduced number of lymph nodes retrieved is associated to VO and SO. These conditions should then be considered in clinical practice for the risk of down staging the N stage. Effect of VO and SO on recovery items after surgery should be further investigated. ERAS protocol application should be implemented to improve recovery outcomes in VO and SO patients undergoing laparoscopic colorectal resection.

The Role of CT-Quantified Body Composition on Longitudinal Health-Related Quality of Life in Colorectal Cancer Patients: The Colocare Study

BACKGROUND

Obesity, defined by body mass index (BMI), measured at colorectal cancer (CRC) diagnosis has been associated with postoperative complications and survival outcomes. However, BMI does not allow for a differentiation between fat and muscle mass. Computed tomography (CT)-defined body composition more accurately reflects different types of tissue and their associations with health-related quality of life (HRQoL) during the first year of disease, but this has not been investigated yet. We studied the role of visceral and subcutaneous fat area (VFA and SFA) and skeletal muscle mass (SMM) on longitudinally assessed HRQoL in CRC patients.

METHODS

A total of 138 newly diagnosed CRC patients underwent CT scans at diagnosis and completed questionnaires prior to and six and twelve months post-surgery. We investigated the associations of VFA, SFA, and SMM with HRQoL at multiple time points.

RESULTS

A higher VFA was associated with increased pain six and twelve months post-surgery (β = 0.06, p = 0.04 and β = 0.07, p = 0.01) and with worse social functioning six months post-surgery (β = -0.08, p = 0.01). Higher SMM was associated with increased pain twelve months post-surgery (β = 1.03, p < 0.01).

CONCLUSIONS

CT-quantified body composition is associated with HRQoL scales post-surgery. Intervention strategies targeting a reduction in VFA and maintaining SMM might improve HRQoL in CRC patients during the first year post-surgery.

The BMI Paradox and Robotic Assisted Partial Nephrectomy

Introduction: Partial nephrectomy (PN), has become the gold standard for the surgical management of small renal masses, due to excellent oncologic control with concomitant preservation of nephron units. However, data regarding the association of obesity with perioperative outcomes following PN are mixed. Therefore, the association between obesity (using BMI) and post-operative complications (POC) rate following Robotic assisted laparoscopic PN (RPNx) was tested.

Methods: Two hundred and fifty-one adult patients who underwent RPNx from 1/2011 to 5/2017 at a single institution, with at least 90 days follow-up were identified and included. No patients were excluded. Electronic medical records were reviewed to record all POC within 90 days of surgery. A piecewise generalized linear model for binary outcomes (logistic) was used to model the proportion of subjects with POC by their BMI. The slope of the line is adjusted to a BMI of 30 Kg/m².

Results: BMI is significantly associated with POC rate. POC rate decreased with increasing BMI below the inflection point of 30 Kg/m² (0.848[0.756, 0.952]) (OR [95% CI], p = 0.005). POC rate was found to increase with increasing BMI above the BMI inflection of 30 Kg/m² (1.102 [1.027, 1.182], p = 0.0071).

Conclusions: In this cohort study, BMI showed an association with PC. It may be important to take BMI into account in surgical and clinical management considerations of RPNx, since higher rates of POC are associated with patients who are underweight, morbidly obese, and even with normal BMI. Further research is required on larger cohorts of RPNx patients to provide better description of this phenomenon and elucidate the role of BMI in development of POC.

Impact of adiposity on staging and prognosis of colorectal cancer

Abdominal visceral fat is a well-recognized a risk for colorectal cancer (CRC). In contrast to the risk for CRC, the impact of adiposity in disease staging and patient survival is less well-established. Our aim was to critically review the literature on the influence of adiposity assessed by different methods routinely used in clinical settings, on CRC staging and prognosis. In the 32 studies reviewed, overweight was initially identified as a survival advantage, an evidence that was later challenged by studies suggesting that body adiposity is likely to have a deleterious effect in CRC outcomes, particularly in males. Hence, whether obesity has a negative impact in CRC staging or prognosis remains controversial. In sum, addressing the impact of body fat in CRC biological behavior is still an unmet need. Understanding how adiposity influences CRC staging and prognosis could allow further patient risk stratification for devising targeted interventions and improve clinical outcomes.

Usefulness of blood flow evaluation by indocyanine green fluorescence system in laparoscopic anterior resection

BACKGROUND

One of the major cause of anastomotic leakage (AL) in anterior resection of the rectum is insufficient blood flow of the remnant colon. The indocyanine green fluorescence system (ICG-FS) can visualize the blood flow of organs intra-operatively. The aim of this study is to investigate the usefulness of ICG-FS for evaluating the blood flow of the remnant colon in laparoscopic anterior resection.

MATERIALS AND METHODS

Rectal cancer patients (n=24) who underwent laparoscopic anterior resection were included in this study. After resection of the rectum, 7.5mg of ICG was administered intravenously, and the blood flow of the oral stump was evaluated by the ICG-FS. The relationship between the fluorescence time (FT) of the oral stump and AL was investigated retrospectively.

RESULT

Two of twenty-four patients (8.3%) suffered AL. The FT of these two cases were over 60 seconds. In the case with the FT was over 80 seconds, we performed additional resection of the late fluorescence portion of the remnant colon and could avoid AL. In patients whose FT was under 60 seconds, no patients suffered AL.

CONCLUSION

ICG-FS may be useful for evaluating the blood flow of the remnant colon to avoid AL in laparoscopic anterior resection. J. Med. Invest. 66 : 65-69, February, 2019.

Computed Tomography-Based Body Composition Is Not Consistently Associated with Outcome in Older Patients with Colorectal Cancer

Background

Current literature is inconsistent in the associations between computed tomography (CT)‐based body composition measures and adverse outcomes in older patients with colorectal cancer (CRC). Moreover, the associations with consecutive treatment modalities have not been studied. This study compared the associations of CT‐based body composition measures with surgery‐ and chemotherapy‐related complications and survival in older patients with CRC.

Materials and Methods

A retrospective single‐center cohort study was conducted in patients with CRC aged ≥65 years who underwent elective surgery between 2010 and 2014. Gender‐specific standardized scores of preoperative CT‐based skeletal muscle (SM), muscle density, intermuscular adipose tissue (IMAT), visceral adipose tissue (VAT), subcutaneous adipose tissue, IMAT percentage, SM/VAT, and body mass index (BMI) were tested for their associations with severe postoperative complications, prolonged length of stay (LOS), readmission, and dose‐limiting toxicity using logistic regression and 1‐year and long‐term survival (range 3.7–6.6 years) using Cox regression. Bonferroni correction was applied to account for multiple testing.

Results

The study population consisted of 378 patients with CRC with a median age of 73.4 (interquartile range 69.5–78.4) years. Severe postoperative complications occurred in 13.0%, and 39.4% of patients died during follow‐up. Dose‐limiting toxicity occurred in 77.4% of patients receiving chemotherapy (n = 53). SM, muscle density, VAT, SM/VAT, and BMI were associated with surgery‐related complications, and muscle density, IMAT, IMAT percentage, and SM/VAT were associated with long‐term survival. After Bonferroni correction, no CT‐based body composition measure was significantly associated with adverse outcomes. Higher BMI was associated with prolonged LOS.

Conclusion

The associations between CT‐based body composition measures and adverse outcomes of consecutive treatment modalities in older patients with CRC were not consistent or statistically significant.

Implications for Practice

Computed tomography (CT)‐based body composition, including muscle mass, muscle density, and intermuscular, visceral, and subcutaneous adipose tissue, showed inconsistent and nonsignificant associations with surgery‐related complications, dose‐limiting toxicity, and overall survival in older adults with colorectal cancer. This study underscores the need to verify whether CT‐based body composition measures are worth implementing in clinical practice.

Colorectal cancer is prevalent in older individuals. This article compares the associations of computed tomography‐based body composition measures with surgery‐ and chemotherapy‐related complications and survival in older patients with colorectal cancer.

Visceral obesity is a preoperative risk factor for postoperative ileus after surgery for colorectal cancer: Single-institution retrospective analysis

AIM

Visceral obesity (VO) reportedly has a stronger association with complications after colorectal surgery than does body mass index. Here, we retrospectively assessed VO as a risk factor for postoperative ileus (POI) after colorectal resection in patients with colorectal cancer.

METHODS

This study included 417 consecutive patients with colorectal cancer who underwent elective surgery at our institute from January 2010 to December 2012. Visceral fat area (VFA) was calculated by image analysis software. VO was defined as VFA ≥100 cm2. We assessed 49 factors, including VO, comorbidities, surgical procedure, and postoperative complications. Data were analyzed using a propensity score-matching strategy.

RESULTS

Postoperative ileus occurred in 18 patients (4.3%) from the entire cohort, and in 14 (5.5%) of the 256 matched patients. Multivariate analysis (n = 417 patients) showed that significant risk factors for POI included VO (OR 7.9, 95% confidence interval [CI] 1.9-32.1, P = .004), open surgery (OR 6.4, 95% CI 1.6-26.7, P = .010), and pelvic/intra-abdominal abscess (OR 11.0, 95% CI 1.1-110.2, P = .041). Propensity score matching showed two independent risk factors in the multivariate analysis: VO (OR 6.2, 95% CI 1.3-30.4, P = .025) and open surgery (OR 9.1, 95% CI 2.0-40.5, P = .004).

CONCLUSION

Visceral obesity may be an independent risk factor for POI in patients with colorectal cancer.

Laparoscopic-assisted colorectal surgery benefits visceral obesity patients: a propensity-matched analysis

BACKGROUND

We aimed to determine the safety and effectiveness of laparoscopic-assisted surgery (LAS) in visceral obesity patients with colorectal cancer (CRC).

PATIENTS AND METHODS

We retrospectively collected the clinical data of consecutive patients who underwent colorectal surgery for CRC between August 2014 and July 2018. The third lumbar vertebra visceral fat area was measured to diagnose visceral obesity. One-to-one propensity score matching was performed to compare the short-term outcomes between the open surgery (OS) and LAS in visceral obesity patients. Univariate and multivariate analyses were performed to evaluate the risk factors of postoperative complications.

RESULTS

A total of 280 visceral obesity patients were included in this study with 140 patients for each group. Compared with the OS group, the LAS group had more lymph nodes harvested, longer surgical duration, and shorter postoperative hospital stay. The overall incidence of complications in OS was significantly higher than LAS (32.1 vs. 20.0%, P=0.021). Multivariate analysis revealed that age of at least 65 years (odds ratio: 1.950, 95% confidence interval: 1.118-3.403; P=0.019) was an independent risk factor for postoperative complications, whereas LAS (odds ratio: 0.523, 95% confidence interval: 0.302-0.908; P=0.021) was a protective factor.

CONCLUSION

LAS in visceral obesity patients with CRC was a safer and less invasive alternative than open surgery, with fewer complications within the first 30 days postoperatively.

Impact of Body Composition on Surgical Outcome in Rectal Cancer Patients, a Retrospective Cohort Study

BACKGROUND

Obesity is becoming a bigger health problem every year. Current research shows that the obesity-related metabolic problems are strongly associated with visceral fat and not subcutaneous fat. Visceral obesity (VO) is associated with a worse postoperative outcome in multiple fields of abdominal surgery. On the other hand, muscle mass is related to better postoperative outcome. In rectal cancer patients, we studied the influence of visceral obesity and muscle mass on postoperative complications.

METHODS

The visceral fat area (VFA) and skeletal muscle area (SMA) were determined on preoperative CT scans in 406 patients. The preoperative comorbidity, per-operative outcome and postoperative complications were extracted retrospectively from the patient files. VO was defined as a VFA > 100 cm². Correlations between body composition, postoperative complications and LOS were studied.

RESULTS

In our study, 67% of the patients were classified as visceral obese. Mean body mass index (BMI) was higher in the VO group (26.6 ± 3.5 vs 23.5 ± 2.8; p < 0.001). Visceral obese patients had a higher prevalence of cardiac comorbidity (29% vs 13% p = 0.001), hypertension (36% vs 20% p = 0.002) and diabetes mellitus (16% vs 5% p = 0.002). In addition, VO patients had more operative blood loss (431 vs 310 mL; p = 0.008), longer operating time (166 vs 149 min p = 0.003) and more wound infections (14% vs 8% p = 0.048). Visceral obesity was associated with more complications (OR: 1.63 p = 0.043) and longer LOS (risk estimate: 1.18 p = 0.009).

CONCLUSION

VO patients more often had a history of cardiac disease, hypertension and diabetes mellitus. Visceral obesity correlated with a worse outcome after surgery for rectal cancer.

Risk factors for early postoperative complications after D3 dissection for stage II or III colon cancer: Supplementary analysis of a multicenter randomized controlled trial in Japan (JCOG0404)

OBJECTIVE

To determine risk factors for early postoperative complications after D3 dissection for stage II/III colon cancer.

BACKGROUND

Identification of risk factors for postoperative complications is essential in patients surgically treated for colon cancer. The Japan Clinical Oncology Group (JCOG) conducted a randomized controlled trial, JCOG0404, to confirm the non-inferiority of laparoscopic surgery (LAP) to open surgery (OP) with D3 dissection for stage II/III colon cancer. This supplementary analysis was made to assess risk factors for surgery requiring D3 dissection using data from JCOG0404.

METHODS

Proportion of postoperative complications of any grade (CTCAE ver. 3.0) until first discharge and risk factors for the most frequent complications were analyzed by univariable and multivariable analysis.

RESULTS

Among 1057 randomized patients treated between October 2004 and March 2009, 520 patients with OP and 525 patients with LAP were analyzed. Overall postoperative complications of all grades occurred in 190 patients (18.2%). Multivariable analysis showed that the risk factors for overall early postoperative complications were OP itself (odds ratio [OR] 2.01, 95% confidence interval [CI]: 1.38-2.91, P = 0.0003) and operation time of >240 minutes (OR 1.94, 95% CI: 1.24-3.02, P = 0.0036). The most frequent adverse event was wound complication (50/1045, 4.8%). In the univariable analysis, reconstruction, greater blood loss, OP, and higher body mass index were significantly associated with wound complication.

CONCLUSION

Open surgery and longer operation time of >240 minutes were significant risk factors for postoperative complications. LAP surgery and shorter operation time could contribute to fewer postoperative complications in patients undergoing colectomy with D3 dissection. (Japan Clinical Oncology Group study JCOG 0404: NCT00147134/UMIN-CTR: C000000105.).

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.

External validation of anastomotic leakage risk analysis system in patients who underwent colorectal resection

BACKGROUND/AIM

One of the most feared complications after colon resection for carcinoma is anastomotic leakage. Prediction of anastomotic leakage can alter pre- and perioperative management of patients. This study validates an anastomotic leakage prediction system.

MATERIALS AND METHODS

Ninety-five patients who underwent colonic resection between 1 January 2016 and 30 January 2017 were included in the study. Patient records and electronic charting system data were used to calculate anastomotic leakage risk on the http://www.anastomoticleak.com/ website.

RESULTS

Fifty-six (58.9%) patients were male and thirty-nine (41.1%) were female. The mean age was 61.7 (min: 33, max: 90). Six (6.3%) patients had anastomotic leakage. According to the ROC analysis, the area under curve for the prediction system was 0.767.

CONCLUSION

The prediction system for anastomotic leakage produced significant results for our patient population. It can be effectively utilized in preoperative and perioperative measures to prevent anastomotic leakage.

Perirenal fat surface area as a risk factor for perioperative difficulties and 30-day postoperative complications in elective colon cancer surgery

AIM

Visceral obesity is associated with perioperative and postoperative complications in colorectal surgery. We aimed to investigate the association between the perirenal fat surface area (PRF) and postoperative complications.

METHOD

Data on 610 patients undergoing curative, elective colon cancer resection between 2006 and 2016 at Stockholm South General Hospital were retrieved from a local quality register. We assessed perioperative and postoperative outcomes using a multinomial regression model adjusted for age, sex, American Society of Anesthesiologists classification and surgical approach (open/laparoscopy) in relation to PRF.

RESULTS

PRF could be measured in 605 patients; the median area was 24 cm² . Patients with PRF ≥ 40 cm² had longer operation time (median 223 vs 184 min), more intra-operative bleeding (250 vs 125 ml), reoperations (11% vs 6%), surgical complications (27% vs 13%) and nonsurgical infectious complications (16% vs 9%) than patients with PRF < 40 cm² , but there were no differences in the need for intensive care or duration of hospital stay. The multivariate analyses revealed an increased risk of any complication [OR 1.68 (95% CI 1.1-2.6)], which was even more pronounced for moderate complications [Clavien-Dindo II, OR 2.14 (CI 1.2-2.4]; Clavien-Dindo III, OR 2.35 (CI 1.0-5.5)] in patients with PRF ≥ 40 vs < 40 cm² . The absolute risk of complications was similar in men and women with PRF ≥ 40 cm² .

CONCLUSION

PRF, an easily measured indirect marker of visceral obesity, was associated with overall and moderate complications in men and women and could serve as a useful tool in the assessment of preoperative risk.

Visceral obesity is a significant risk factor for incisional hernia after laparoscopic colorectal surgery: A single-center review

INTRODUCTION

Although laparoscopic surgery uses relatively small incisions, incisional hernia after surgery is not uncommon. However, the incidence of incisional hernia and its risk factors are not well known. The purpose of our study was to investigate risk factors for incisional hernia after laparoscopic colorectal cancer surgery.

METHODS

The study group consisted of 212 patients who underwent laparoscopic colorectal cancer surgery at Hiroshima Prefectural Hospital between November 2008 and October 2013. Diagnosis of incisional hernia was performed by postoperative CT. The visceral fat area (VFA) and subcutaneous fat area at the level of the umbilicus were calculated using an image analysis system. For statistical analysis, Fisher's exact test or Student's t-test were used for univariate analysis, and logistic regression analysis was used for multivariate analysis. The cut-off value for risk factors was calculated from the receiver-operator curve.

RESULTS

Incisional hernia was observed in 18 patients (8.5%). On univariate analysis, female sex (P = 0.04), older age (P = 0.02), subcutaneous fat area (P < 0.01), VFA (P = 0.02), and BMI >25 kg/m² (P < 0.01) were significant risk factors for incisional hernia. The predictive cut-off values were as follows: age, 72 years; subcutaneous fat area, 110 cm² ; VFA, 110 cm² ; and albumin concentration, 3.9 g/dL. On multivariate analysis, a VFA >110 cm² (P < 0.01) and female sex (P = 0.01) were retained as independent risk factors for incisional hernia.

CONCLUSION

After laparoscopic colorectal cancer surgery, a higher VFA and female sex are independent risk factors for incisional hernia.

Body Fatness, Adipose Tissue Compartments, and Biomarkers of Inflammation and Angiogenesis in Colorectal Cancer: The ColoCare Study

BACKGROUND

Adiposity has been linked to both risk and prognosis of colorectal cancer; however, the impact of different fat areas [visceral (VFA) vs. subcutaneous fat area (SFA)] is unclear. We investigated associations between adiposity and biomarkers of inflammation and angiogenesis among patients with colorectal cancer.

METHODS

Preoperative serum samples and computed tomography scans were obtained from 188 patients diagnosed with primary invasive stage I-IV colorectal cancer enrolled in the ColoCare Study. Adiposity was assessed by area-based quantification of VFA, SFA, and VFA:SFA ratio on spinal levels L3/L4 and L4/L5. Circulating levels of inflammation (CRP, SAA, sICAM-1, and sVCAM-1) and angiogenesis (VEGF-A and VEGF-D) were assessed from patient sera on the Meso Scale Discovery platform. Partial correlations and regression analyses, adjusted for age, sex, and tumor stage, were performed.

RESULTS

VFA was moderately correlated with CRP and SAA (CRP: L3/L4 and L4/L5:r = 0.21, P = 0.01; SAA: L3/L4:r = 0.17, P = 0.04). The correlation between SFA and the measured biomarkers were weak (r ≤ 0.13, not significant). The ratio of VFA:SFA at L3/L4 was moderately correlated with VEGF-A (r = 0.28, P = 0.0008) and SAA (r = 0.24, P = 0.006), and less so with CRP (r = 0.18, P = 0.04) and sICAM-1 (r = 0.18, P = 0.04). Similar correlations were found for the VFA:SFA ratio at L4/L5.

CONCLUSIONS

We observed an association between visceral adiposity and biomarkers of inflammation and angiogenesis in colorectal cancer. In particular, the VFA:SFA ratio was correlated with circulating levels of the proangiogenic biomarker VEGF-A.

IMPACT

Our findings support a direct association of visceral adipose tissue with inflammatory and angiogenic processes, which play fundamental roles in the development and progression of colorectal cancer.

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.

Higher visceral fat area/subcutaneous fat area ratio measured by computed tomography is associated with recurrence and poor survival in patients with mid and low rectal cancers

PURPOSE

Obesity is thought to influence postoperative complications and recurrence of mid and low rectal cancer (MLRC) because of intraoperative technical difficulties. However, few reports have described the relationship between obesity indices and the clinical outcomes of MLRC. This study aimed to investigate the association between visceral obesity on computed tomography (CT) and oncolofical outcomes after surgery for MLRC and identify the obesity index that most accurately reflects clinical outcomes.

METHODS

We investigated 125 patients who underwent curative resection for MLRC between 2004 and 2010. Visceral fat area (VFA) was defined as the umbilicus-level intra-abdominal adipose tissue area measured by CT. Body mass index (BMI), total fat area, VFA, subcutaneous fat area (SFA) and VFA/SFA ratio (V/S ratio) were analysed.

RESULTS

The median follow-up time was 60.3 months (range, 38.2-122.6 months). Recurrence was detected in 28 (22.4%) patients. Among the various obesity indices, recurrence was significantly associated with V/S ratio only (1.02 ± 0.45 versus 0.86 ± 0.34; P = 0.046). Stage, preoperative carcinoembryonic antigen level, V/S ratio, lymphatic invasion and perineural invasion were significantly associated with recurrence on univariate analysis, while only V/S ratio (P = 0.019; 95% confidence interval, 1.22 to 9.09) was significantly associated with recurrence on multivariate analysis. Disease-free and overall survival of the obese group (V/S ratio > 1.0) were shorter than those of the non-obese group.

CONCLUSIONS

V/S ratio is the optimal obesity index for predicting stage I-III MLRC recurrence.

Visceral fat area measured with computed tomography does not predict postoperative course in Crohn´s disease patients

The role of visceral fat measured by computer tomography is yet not well defined in patients with Crohn's disease. Therefore, the present study was designed to assess the impact of visceral fat area on postoperative short-term outcome and surgical characteristics. We analyzed 95 patients, who underwent intestinal resection for symptomatic Crohn's disease at an academic tertiary referral center between 2003 and 2008. Visceral fat area was measured on preoperative computed tomography scans. Postoperative morbidity was graded according to the Clavien-Dindo classification. Visceral fat area was correlated with baseline characteristics, disease phenotype and 30-day morbidity. Body mass index and age were significantly associated with a higher visceral fat area (p = 0.001). Overall 19 (20.0%) postoperative complications were observed, of whom 7 (7.4%) patients required surgical re-intervention. No significant difference was found with regard to visceral fat area between patients with an uneventful and eventful postoperative course (no complications: median visceral fat area 52.0 cm² SD 59.7, complications: 41.3 cm² SD 42.8; p = 0.465). In contrast to current literature, we cannot support the role of visceral fat area for predicting postoperative course in Crohn's disease. In addition, no correlation of the visceral fat area and disease behavior was detected.

Does obesity impact postoperative outcomes following robotic-assisted surgery for rectal cancer?

INTRODUCTION

Obesity has been identified as a risk factor for both conversion and severe postoperative morbidity in patients undergoing laparoscopic rectal resection. Robotic-assisted surgery (RAS) is proposed to overcome some of the technical limitations associated with laparoscopic surgery for rectal cancer. The aim of our study was to determine if obesity remains a risk factor for severe morbidity in patients undergoing robotic-assisted rectal resection.

PATIENTS

This study was a retrospective review of a prospective database. A total of 183 patients undergoing restorative RAS for rectal cancer between 2007 and 2016 were divided into 2 groups: control (BMI < 30 kg/m²; n = 125) and obese (BMI ≥ 30 kg/m²; n = 58). Clinicopathologic data, 30-day postoperative morbidity, and perioperative outcomes were compared between groups. The main outcome was severe postoperative morbidity defined as any complication graded Clavien-Dindo ≥ 3.

RESULTS

Control and obese groups had similar clinicopathologic characteristics. Severe complications were observed in 9 (7%) and 4 (7%) patients, respectively (p > 0.99). Obesity did not impact conversion, anastomotic leak rate, length of stay, or readmission but was significantly associated with increased postoperative morbidity (29 vs. 45%; p = 0.04) and especially more postoperative ileus (11 vs. 26%; p = 0.01). Obesity and male gender were the two independent risk factors for postoperative overall morbidity (OR 1.97; 95% CI 1.02-3.94; p = 0.04 and OR 2.23; 95% CI 1.10-4.76; p = 0.03, respectively).

CONCLUSION

‎Obesity did not impact severe morbidity or conversion rate following RAS for rectal cancer but remained a risk factor for overall morbidity and especially postoperative ileus.

Impact of Visceral Obesity and Sarcopenia on Short-Term Outcomes After Colorectal Cancer Surgery

BACKGROUND

With the increased prevalence of obesity and sarcopenia, those patients with both visceral obesity and sarcopenia were at higher risk of adverse outcomes.

AIM

The aim of this study was to ascertain the combined impact of visceral obesity and sarcopenia on short-term outcomes in patients undergoing colorectal cancer surgery.

METHODS

We conducted a prospective study from July 2014 to February 2017. Patients' demographic, clinical characteristics, physical performance, and postoperative short-term outcomes were collected. Patients were classified into four groups according to the presence of sarcopenia or visceral obesity. Clinical variables were compared. Univariate and multivariate analyses evaluating the risk factors for postoperative complications were performed.

RESULTS

A total of 376 patients were included; 50.8 and 24.5% of the patients were identified as having "visceral obesity" and "sarcopenia," respectively. Patients with sarcopenia and visceral obesity had the highest incidence of total, surgical, and medical complications. Patients with sarcopenia or/and visceral obesity all had longer hospital stays and higher hospitalization costs. Age ≥ 65 years, visceral obesity, and sarcopenia were independent risk factors for total complications. Rectal cancer and visceral obesity were independent risk factors for surgical complications. Age ≥ 65 years and sarcopenia were independent risk factors for medical complications. Laparoscopy-assisted operation was a protective factor for total and medical complications.

CONCLUSION

Patients with both visceral obesity and sarcopenia had a higher complication rate after colorectal cancer surgery. Age ≥ 65 years, visceral obesity, and sarcopenia were independent risk factors for total complications. Laparoscopy-assisted operation was a protective factor.

Influence of Visceral Fat in the Outcomes of Colorectal Cancer

AIM

To determine the relationship of visceral fat (VF) with the surgical outcome of the patients with colorectal cancer (CRC) submitted to curative surgery.

METHODS

Retrospective analysis of all patients submitted to CRC surgery during 3 years with a minimum of 5 years of follow-up. We assessed the length of hospital stay, complications, pathologic reports, surgical re-interventions and hospital re-admissions, relapses, survival time and disease-free time. VF was calculated based on patients' pre-operative CT-scan. The patients were divided into quartiles according to the VF area. Linear regression models and logistic regression models were used to establish a relationship between VF and all data collected.

RESULTS

The study included 199 patients (129 with colon cancer [CC] and 70 with rectal cancer). The average area of VF was 115.7 cm2. Patients with CRC revealed a direct relationship between VF and postoperative complications (p = 0.043), anastomotic leakage (p = 0.009) and re-operation (p = 0.005). The subgroup of patients with CC had an inverse association between VF and lymph nodes harvested (p = 0.027). Survival analyses did not reveal significant differences.

CONCLUSION

VF has an influence on postoperative complications, anastomotic leakage and re-operation. A negative influence of VF on lymph nodes harvested was observed on CC patients.

Sarcopenia is negatively associated with long-term outcomes in locally advanced rectal cancer

BACKGROUND

The association of sarcopenia and visceral obesity to treatment outcome is not clear for locally advanced rectal cancer. This study evaluates the influence of skeletal muscle and visceral fat on short-term and long-term outcomes in locally advanced rectal cancer patients treated with neoadjuvant chemoradiation therapy followed by curative resection.

METHODS

A total of 188 patients with locally advanced cancer were included between January 2009 and December 2013. Neoadjuvant chemoradiotherapy was followed by curative resection. Sarcopenia and visceral obesity were identified in initial staging CT by measuring the muscle and visceral fat area at the third lumbar vertebra level.

RESULTS

Among the 188 included patients, 74 (39.4%) patients were sarcopenic and 97 (51.6%) patients were viscerally obese. Sarcopenia and high levels of preoperative carcinoembryonic antigen were significant prognostic factors for overall survival (P = 0.013, 0.014, respectively) in the Cox regression multivariate analysis. Visceral obesity was not associated with overall survival; however, it did tend to shorten disease-free survival (P = 0.079).

CONCLUSIONS

Sarcopenia is negatively associated with overall survival in locally advanced rectal cancer patients who underwent neoadjuvant chemoradiation therapy and curative resection. Visceral obesity tended to shorten disease-free survival. Future studies should be directed to optimize patient conditions according to body composition status.

The relationship between body mass index and short term postoperative outcomes in patients undergoing potentially curative surgery for colorectal cancer: A systematic review and meta-analysis

BACKGROUND

The prevalence of obesity has increased worldwide over the last few decades, and is a well-recognized risk factor for colorectal cancer. Surgical site infection is the most frequent complication following surgery for colorectal cancer, and the main cause of postoperative morbidity. The aim of the present systematic review and meta-analysis was to examine the relationship between increasing BMI and postoperative surgical site infection following surgery for colorectal cancer.

METHODS

A systemic literature search was conducted using Medline, PubMed, Embase (Ovid) and Web of Science databases from inception to the end of August 2016. Studies examining the relationship between obesity and surgical site infection following surgery for colorectal cancer were included. Analysis of the data was performed using Review Manager version 5.3(The Nordic Cochrane Centre, The Cochrane Collaboration, Copen-hagen, Denmark,) RESULTS: In this meta-analysis, a total of 9535 patients from 16 studies were included. BMI <30 vs ≥30kg/m² was used to examine the association of obesity and surgical site infection in patients from Western countries. The estimated pooled OR demonstrated that obesity increased the risk of surgical site infection by approximately 100% (OR=2.13; 95% CI 1.66-2.72, p<0.001).BMI <25 vs ≥25kg/m² was used to examine the association of obesity and surgical site infection from Asian countries. The estimated pooled OR demonstrated that obesity increased the risk of surgical site infection by approximately 60% (OR=1.63; 95% CI 1.29-2.06, p<0.001). There was little evidence of publication bias in the meta-analysis.

CONCLUSION

From this systematic review and meta-analysis there was good evidence that obesity was associated with a significantly higher risk of developing surgical site infection following surgery for colorectal cancer in both ethnic groups. The magnitude of the effect warrants further investigation.

Laparoscopic colectomy in the obese, morbidly obese, and super morbidly obese: when does weight matter?

PURPOSE

Previous studies have demonstrated that obese patients (BMI >30) undergoing laparoscopic colectomy have longer operative times and increased complications when compared to non-obese cohorts. However, there is little data that specifically evaluates the outcomes of obese patients based on the degree of their obesity. The aim of this study was to evaluate the impact of increasing severity of obesity on patients undergoing laparoscopic colectomy.

METHODS

A retrospective review was performed of all patients undergoing laparoscopic colectomy between 1996 and 2013. Patients were classified according to their BMI as obese (BMI 30.0-39.9), morbidly obese (BMI 40.0-49.9), and super obese (BMI >50). Main outcome measures included conversion rate, operative time, estimated blood loss, post-operative complications, and length of stay.

RESULTS

There were 923 patients who met inclusion criteria. Overall, 604 (65.4%), 257 (27.9%), and 62 (6.7%) were classified as obese (O), morbidly obese (MO), and super obese (SO), respectively. Clinicopathologic characteristics were similar among the three groups. The SO group had significantly higher conversion rates (17.7 vs. 7 vs. 4.8%; P = 0.031), longer average hospital stays (7.1 days vs. 4.9 vs. 3.4; P = 0.001), higher morbidity (40.3 vs. 16.3 vs. 12.4%; P = 0.001), and longer operative times (206 min vs. 184 vs. 163; P = 0.04) compared to the MO and O groups, respectively. The anastomotic leak rate in the SO (4.8%; P = 0.027) and MO males (4.1%; P = 0.033) was significantly higher than MO females (2.2%) and all obese patients (1.8%).

CONCLUSION

Increasing severity of obesity is associated with worse perioperative outcomes following laparoscopic colectomy.

Obesity as predictor of postoperative outcomes in liver transplant candidates: Review of the literature and future perspectives

BACKGROUND

Current American and European guidelines consider a pre-transplant BMI ≥40kg/m2 as a relative contraindication for liver transplantation but this recommendation is graded as uncertain and requires further research. Moreover, conflicting results are reported on the predictive value of BMI 30-39.9kg/m2 on post-transplant complication and mortality risk.

AIM

This study analyzed the data of the literature on the effect of all three BMI classes of obesity on postoperative outcomes in liver transplantation.

MATERIALS AND METHODS

A PubMed and Cochrane Library search was conducted from inception to October 2015.

RESULTS

Analysis of the literature demonstrates that discrepancies among studies are mainly either due to limitations of BMI per se, the different BMI cut-offs used to select patients with obesity or reference group and the different outcomes considered. Moreover, the evaluation of visceral adipose tissue and the detrimental effect of muscle mass reduction in presence of obesity are never considered.

CONCLUSIONS

BMI assessment should be used as a preliminary method to evaluate obesity. Subsequently, the assessment of visceral adipose tissue and muscle mass should complete the preoperative evaluation of liver transplant candidates. This innovative approach could represent a new field of research in liver transplantation.

A quantified risk-scoring system and rating model for postsurgical gastroparesis syndrome in gastric cancer patients

BACKGROUND AND OBJECTIVES

The study aimed to investigate the relationship between obesity and postsurgical gastroparesis syndrome (PGS), and to construct a scoring system and a risk model to identify patients at high risk.

METHODS

A total of 634 patients were retrospectively analyzed. Clinical characteristics were evaluated via receiver operating characteristic (ROC) curve analysis. Logistic analysis was performed to determine the independent predictive indicators of PGS. A scoring system consisting of these indicators and a risk-rating model were constructed and evaluated via ROC curve analysis.

RESULTS

Based on the ROC curves, the visceral fat area (VFA) cutoff value for PGS was 94.00. Logistic analysis showed that visceral obesity (VFA ≥ 94.00 cm² ), the reconstruction technique, and tumor size were independent prognostic factors for PGS. The scoring system could predict PGS reliably with a high area under the ROC curve ([AUC] = 0.769). A high-risk rating had a high AUC (AUC I = 0.56, AUC II = 0.65, and AUC III = 0.77), indicating that the risk-rating model could effectively screen patients at high risk of PGS.

CONCLUSIONS

Visceral obesity defined by VFA effectively predicted PGS. Our scoring system may be a reliable instrument for identifying patients most at risk of PGS.

Associations of adipose and muscle tissue parameters at colorectal cancer diagnosis with long-term health-related quality of life

PURPOSE

Increased visceral adiposity (visceral obesity) and muscle wasting (sarcopenia) at colorectal cancer (CRC) diagnosis, quantified by computed tomography (CT) image analysis, have been unfavorably associated with short-term clinical outcomes and survival, but associations with long-term health-related quality of life (HRQoL) have not been investigated. We studied associations of visceral adiposity, muscle fat infiltration, muscle mass, and sarcopenia at CRC diagnosis with HRQoL 2-10 years post-diagnosis.

METHODS

A cross-sectional study was conducted in 104 stage I‒III CRC survivors, diagnosed at Maastricht University Medical Center+, the Netherlands (2002-2010). Diagnostic CT images at the level of the third lumbar vertebra were analyzed to retrospectively determine visceral adipose tissue area (cm2); intermuscular adipose tissue area (cm2) and mean muscle attenuation (Hounsfield units) as measures of muscle fat infiltration; and skeletal muscle index (SMI, cm2/m2) as measure of muscle mass and for determining sarcopenia.

RESULTS

Participants showed a large variation in body composition parameters at CRC diagnosis with a mean visceral adipose tissue area of 136.1 cm2 (standard deviation: 93.4) and SMI of 47.8 cm2/m2 (7.2); 47% was classified as being viscerally obese, and 32% as sarcopenic. In multivariable linear regression models, associations of the body composition parameters with long-term global quality of life, physical, role and social functioning, disability, fatigue, and distress were not significant, and observed mean differences were below predefined minimal important differences.

CONCLUSIONS

Although visceral obesity and sarcopenia are relatively common at CRC diagnosis, we found no significant associations of these parameters with long-term HRQoL in stage I-III CRC survivors.

BMI as a Predictor for Perioperative Outcome of Laparoscopic Colorectal Surgery: a Pooled Analysis of Comparative Studies

BACKGROUND

There has been a long-lasting controversy about whether higher BMI is associated with worse perioperative outcomes of laparoscopic colorectal surgery. Recently, a number of newly published investigations have made it possible to draw a quantitative conclusion.

OBJECTIVE

We conducted this comprehensive meta-analysis to clarify the exact effect that BMI imposes on perioperative outcome of laparoscopic colorectal surgery.

DATA SOURCES

We systematically searched MEDLINE, Embase, and Cochrane Library databases to identify all relevant studies.

STUDY SELECTION

Comparative studies in English that investigated perioperative outcome of laparoscopic colorectal surgery for patients with different BMIs were included. Quality of studies was evaluated by using the Newcastle-Ottawa Scale.

INTERVENTION

The risk factor of interest was BMI.

MAIN OUTCOME MEASURES

Effective sizes were pooled under a random-effects model to evaluate preoperative, intraoperative, and postoperative outcomes.

RESULTS

A total of 43 studies were included. We found that higher BMI was associated with significantly longer operative time (p < 0.001), greater blood loss (p = 0.01), and higher incidence of conversion to open surgery (p < 0.001). Moreover, BMI was a risk factor for overall complication rates (p < 0.001), especially for ileus (p = 0.02) and events of the urinary system (p = 0.03). Significant association was identified between higher BMI and risk of surgical site infection (p < 0.001) and anastomotic leakage (p = 0.02). Higher BMI might also led to a reduced number of harvest lymph nodes for patients with colorectal cancer (p = 0.02). The heterogeneity test identified no significant cross-study heterogeneity, and the results of cumulative meta-analysis, sensitivity analysis, and the publication bias test verified the reliability of our study.

LIMITATIONS

Most studies included were retrospectively designed.

CONCLUSIONS

Body mass index is a practical and valuable measurement for the prediction of the perioperative outcome of laparoscopic colorectal surgery. Higher BMI is associated with worse perioperative outcome. More accurate conclusions, with more precise cutoff values, can be achieved by future well-designed prospective investigations.

Prognostic Value of Computed Tomography: Measured Parameters of Body Composition in Primary Operable Gastrointestinal Cancers

Background

Previous reports suggest that body composition parameters can be used to predict outcomes for patients with gastrointestinal (GI) cancers. However, evidence for an association with long-term survival is conflicting, with much of the data derived from patients with advanced disease. This study examined the effect of body composition on survival in primary operable GI cancer.

Methods

Patients with resectable adenocarcinoma of the GI tract (esophagus, stomach, colon, rectum) between 2006 and 2014 were identified from a prospective database. Computed tomography (CT) scans were analyzed using a transverse section at L3 to calculate sex-specific body composition indices for skeletal muscle, visceral fat, and subcutaneous fat. Kaplan–Meier and log-rank analysis were used to compare unadjusted survival. Multivariate survival analyses were performed using a proportional hazards model.

Results

The study enrolled 447 patients (191 woman and 256 men) with esophagogastric (OG) (n = 108) and colorectal (CR) (n = 339) cancer. Body composition did not predict survival for the OG cancer patients. Among the CR cancer patients, survival was shorter for those with sarcopenia (p = 0.017) or low levels of subcutaneous fat (p = 0.005). Older age (p = 0.046) and neutrophilia (p = 0.013) were associated with sarcopenia in patients with CR. Tumor stage (p = 0.033), neutrophil count (p = 0.011), and hypoalbuminemia (p = 0.023) were associated with sarcopenia in OG cancer patients. In the multivariate analysis, no single measure of body composition was an independent predictor of reduced survival.

Conclusion

Sarcopenia and reduced subcutaneous adiposity are associated with reduced survival for patients with primary operable CR cancer. However, in this study, no parameter of body composition was an independent prognostic marker when considered with age, tumor stage, and systemic inflammation.

Risk factors for anastomotic leakage after laparoscopic surgery with the double stapling technique for stage 0/I rectal carcinoma: a subgroup analysis of a multicenter, single-arm phase II trial

PURPOSE

The aim of this study was to determine the risk factors for anastomotic leakage after laparoscopic rectal surgery.

METHODS

We conducted a prospective trial involving 395 patients with stage 0/I rectal carcinoma who underwent laparoscopic low anterior resection using a double stapling technique. Data concerning variables related to patient background, tumors and surgical factors were evaluated. The outcomes with respect to anastomotic leakage were recorded, and univariate and multivariate analyses were performed to identify relevant risk factors.

RESULTS

The overall anastomotic leakage rate was 8.4%. A univariate analysis showed male gender (P = 0.006) and preoperative blood sugar level (P = 0.0034) to be significantly associated with anastomotic leakage. The variables of gender, preoperative blood sugar level, American Society of Anesthesiologists (ASA) classification (P = 0.15), transanal decompression tube (P = 0.06) and number of stapler cartridges used for rectal transection (P = 0.18) were selected for the multivariate analysis because of their P values being <0.2. The multivariate analysis identified male gender (odds ratio 4.12, P = 0.006) and the absence of a transanal decompression tube (odds ratio 3.11, P = 0.0484) as independent risk factors predicting anastomotic leakage.

CONCLUSIONS

Male gender and the absence of a transanal decompression tube appeared to be independent risk factors for anastomotic leakage. Insertion of a transanal decompression tube may help prevent anastomotic leakage after low anterior resection, particularly in male patients.

Quantitative Assessment of Visceral Obesity and Postoperative Colon Cancer Outcomes

BACKGROUND

Quantitative computed tomography (CT) assessment of visceral adiposity may be superior to body mass index (BMI) as a predictor of surgical morbidity. We sought to examine the association of CT measures of obesity and BMI with short-term postoperative outcomes in colon cancer patients.

METHODS

In this retrospective study, 110 patients treated with colectomy for stage I-III colon cancer were classified as obese or non-obese by preoperative CT-based measures of adiposity or BMI [obese: BMI ≥ 30 kg/m², visceral fat area (VFA) to subcutaneous fat area ratio (V/S) ≥0.4, and VFA > 100 cm²]. Postoperative morbidity and mortality rates were compared.

RESULTS

Obese patients, by V/S and VFA but not BMI, were more likely to be male and have preexisting hypertension and diabetes. The overall complication rate was 25.5%, and there were no mortalities. Obese patients by VFA (with a trend for V/S but not BMI) were more likely to develop postoperative complications as compared to patients classified as non-obese: VFA (30.5 vs.10.7%, p = 0.03), V/S (29.2 vs. 9.5%, p = 0.05), and BMI (32.4 vs. 21.9%, p = 0.23).

CONCLUSIONS

Elevated visceral obesity quantified by CT is associated with the presence of key metabolic comorbidities and increased postoperative morbidity and may be superior to BMI for risk stratification.

Survival outcomes following laparoscopic versus open D3 dissection for stage II or III colon cancer (JCOG0404): a phase 3, randomised controlled trial

BACKGROUND

Although benefits of laparoscopic surgery compared with open surgery have been suggested, the long-term survival of patients undergoing laparoscopic surgery for colon cancer requiring Japanese D3 dissection remains unclear. We did a randomised controlled trial to establish non-inferiority of laparoscopic surgery to open surgery.

METHODS

We did an open-label, multi-institutional, randomised, two-arm phase 3 trial in 30 hospitals in Japan. Patients aged 20-75 years who had histologically proven colon cancer; tumours located in the caecum or ascending, sigmoid, or rectosigmoid colon; T3 or deeper lesions without involvement of other organs, node stages N0-2, and metastasis stage M0; and tumour size of 8 cm or smaller were included. Only accredited surgeons did surgery as an operator or instructor. Patients were randomly assigned (1:1) preoperatively to undergo D3 resection either by an open route or a laparoscopic route, via phone call or fax to the Japan Clinical Oncology Group (JCOG) Data Center. Randomisation used a minimisation method with a biased-coin assignment according to tumour location (caecum, ascending vs sigmoid, rectosigmoid) and institution. The primary endpoint was overall survival and was analysed by intention to treat. The non-inferiority margin for the hazard ratio (HR) was set at 1·366. This study is registered with UMIN Clinical Trials Registry, number C000000105, and ClinicalTrials.gov, number NCT00147134.

FINDINGS

Between Oct 1, 2004, and March 27, 2009, 1057 patients were randomly assigned to either open surgery (n=528) or laparoscopic surgery (n=529). 5-year overall survival was 90·4% (95% CI 87·5-92·6) for open surgery and 91·8% (89·1-93·8) for laparoscopic surgery. Laparoscopic D3 surgery was not non-inferior to open surgery for overall survival (HR 1·06, 90% CI 0·79-1·41; p_{non-inferiority}=0·073). 65 (13%) patients in the open surgery group and 53 (10%) patients in the laparoscopic surgery group had grade 2-4 adverse events. Grade 2-4 adverse events included diarrhoea (15 [3%] in the open surgery group vs 14 [3%] in the laparoscopic surgery group), paralytic ileus (six [1%] vs nine [2%]), and small intestine bowel obstruction (16 [3%] vs 11 [2%]). Two treatment-related deaths occurred in the open surgery group: one patient died 7 days after surgery (probably due to myocardial infarction), and one patient died from febrile neutropenia, pneumonia, diarrhoea, and gastrointestinal haemorrhage during postoperative chemotherapy.

INTERPRETATION

Laparoscopic D3 surgery was not non-inferior to open D3 surgery in terms of overall survival for patients with stage II or III colon cancer. However, because overall survival in both groups was similar and better than expected, laparoscopic D3 surgery could be an acceptable treatment option for patients with stage II or III colon cancer.

FUNDING

National Cancer Center Research and Development Fund, Grant-in-Aid for Cancer Research, and Health and Labour Sciences Research Grant for Clinical Cancer Research from the Ministry of Health, Labour and Welfare of Japan.

Computed Tomography Morphometrics and Pulmonary Intolerance in Endometrial Cancer Robotic Surgery

STUDY OBJECTIVES

To identify morphometric characteristics of obese patients that best predict pulmonary intolerance to robotic pelvic surgery using a novel method for quantifying adipose distribution.

DESIGN

Retrospective study (Canadian Task Force classification II-2).

SETTING

University hospital.

PATIENTS

Fifty-nine patients with endometrial cancer who underwent robotic hysterectomy and lymphadenectomy between April 2008 and May 2014 and also underwent perioperative computed tomography (CT) imaging within 1 year.

INTERVENTION

Visceral fat volume (VFV) and subcutaneous fat volume (SFV) were quantified through waist circumference measurements along with average volume estimation of slices taken at 3 levels: mid-waist, L2-L3, and L4-L5. Mean and maximum values were obtained for intraoperative physiological data.

MEASUREMENTS AND MAIN RESULTS

The patients' mean body mass index (BMI) was 34 (range, 20-59). Along with waist circumference, VFV and SFV quantified by CT at the mid-waist, L2-L3, and L4-L5 levels were all significant independent predictors for peak airway pressure (PAP; average and maximum) and plateau airway pressure (Pplat; average and maximum) on multivariate regression analysis after adjustment for age, ethnicity, diabetes, hypertension, pulmonary disease, smoking, obstructive sleep apnea, American Society of Anesthesiologists classification, and duration of anesthesia. Compared with the other CT parameters, L2-L3 VFV was the best predictor of average PAP (β = 0.398; p = .002), maximum PAP (β = 0.493; p < .001), average Pplat (β = 0.536; p < .001), and maximum Pplat (β = 0.573; p < .001).

CONCLUSION

These novel CT morphometric measurements represent valid predictors of pulmonary intolerance to robotic surgery in obese patients. Of the measures analyzed, VFV at L2-L3 best predicts pulmonary tolerance in obese patients.

The influence of obesity and body mass index on the outcome of laparoscopic colorectal surgery: a systematic literature review

AIM

The relationship between obesity, body mass index (BMI) and laparoscopic colorectal resection is unclear. Our object was to assess systematically the available evidence to establish the influence of obesity and BMI on the outcome of laparoscopic colorectal resection.

METHOD

A search of PubMed/Medline databases was performed in May 2015 to identify all studies investigating the impact of BMI and obesity on elective laparoscopic colorectal resection performed for benign or malignant bowel disease. Clinical end-points examined included operation time, conversion rate to open surgery, postoperative complications including anastomotic leakage, length of hospital stay, readmission rate, reoperation rate and mortality. For patients who underwent an operation for cancer, the harvested number of lymph nodes and long-term oncological data were also examined.

RESULTS

Forty-five studies were analysed, the majority of which were level IV with only four level III (Oxford Centre for Evidence-based Medicine 2011) case-controlled studies. Thirty comparative studies containing 23 649 patients including 17 895 non-obese and 5754 obese showed no significant differences between the two groups with respect to intra-operative blood loss, overall postoperative morbidity, anastomotic leakage, reoperation rate, mortality and the number of retrieved lymph nodes in patients operated on for malignancy. Most studies, including 15 non-comparative studies, reported a longer operation time in patients who underwent a laparoscopic procedure with the BMI being an independent predictor in multivariate analyses for the operation time.

CONCLUSION

Laparoscopic colorectal resection is safe and technically and oncologically feasible in obese patients. These results, however, may vary outside of high volume centres of expertise.

Robot-assisted versus laparoscopic surgery for lower rectal cancer: the impact of visceral obesity on surgical outcomes

PURPOSE

The purpose of this study was to evaluate the advantages of robot-assisted laparoscopic surgery (RALS) for lower rectal cancer and for visceral obesity cases, which have been regarded as challenging situations in rectal cancer surgery, comparing their surgical outcomes with those of conventional laparoscopic surgery (CLS).

METHODS

Patients who underwent robotic or laparoscopic total mesorectal excision for rectal cancer were included in this retrospective study. Surgical outcomes including perioperative, postoperative, and pathological data were compared between the RALS and CLS groups. Patients were stratified into obese and non-obese groups according to visceral fat area (VFA). Obesity was defined by VFA ≥130 cm(2).

RESULTS

Two hundred thirty-six patients were enrolled, including 127 cases in the RALS group and 109 cases in the CLA group. A total of 82 (34.7 %) cases were categorized as VFA obese, including 52 cases in the RALS and 30 cases in the CLS groups. RALS for lower rectal cancer was associated with less blood loss (p = 0.007), a lower overall complication rate (9.4 % in RALS vs 23.9 % in CLS, p = 0.003), and shorter postoperative stay (p < 0.01) than CLS, with similar operative time and pathological results. The overall complication rate was significantly lower in the RALS group with VFA obesity; blood loss was significantly less and the postoperative stay was shorter in the RALS group with visceral obesity.

CONCLUSIONS

The present study demonstrated that RALS has some advantages in terms of surgical outcomes over CLS in challenging situations of rectal cancer surgery, such as lower rectal cancer cases and visceral obesity cases.