Variaciones anatómicas en la vascularización del colon derecho y su implicancia en la escisión completa del mesocolon con linfadenectomía D3. Estudio de corte transversal / Anatomical variations in right colon vascularization: its implication in complete mesocolic excision with D3 lymphadenectomy. A cross-sectional study

Introducción: La escisión completa del mesocolon con linfadenectomía D3 (CME-D3) mejora los resultados de los pacientes operados por cáncer del colon. Reconocer adecuadamente la anatomía vascular es fundamental para evitar complicaciones. Objetivo: El objetivo primario fue determinar la prevalencia de las variaciones anatómicas de la arteria mesentérica superior (AMS) y sus ramas en relación a la vena mesentérica superior (VMS). El objetivo secundario fue evaluar la asociación entre las distintas variantes anatómicas y el sexo y la etnia de lo pacientes. Diseño: Estudio de corte transversal. Material y métodos: Se incluyeron 225 pacientes con cáncer del colon derecho diagnosticados entre enero 2017 y diciembre de 2020. Dos radiólogos independientes describieron la anatomía vascular observada en las tomografías computadas. Según la relación de las ramas de la AMS con la VMS, la población fue dividida en 2 grupos y subdividida en 6 (1a-c, 2a-c). Resultados: La arteria ileocólica fue constante, transcurriendo en el 58,7% de los casos por la cara posterior de la VMS. La arteria cólica derecha, presente en el 39,6% de los pacientes, cruzó la VMS por su cara anterior en el 95,5% de los casos. La variante de subgrupo más frecuente fue la 2a seguida por la 1a (36,4 y 24%, respectivamente). No se encontró asociación entre las variantes anatómicas y el sexo u origen étnico. Conclusión: Las variaciones anatómicas de la AMS y sus ramas son frecuentes y no presentan un patrón predominante. No hubo asociación entre las mismas y el sexo u origen étnico en nuestra cohorte. El reconocimiento preoperatorio de estas variantes mediante angiotomografía resulta útil para evitar lesiones vasculares durante la CME-D3. (AU)

Background: Complete mesocolic excision with D3 lymphadenectomy (CME-D3) improves the outcomes of patients operated on for colon cancer. Proper recognition of vascular anatomy is essential to avoid complications. Aim: Primary outcome was to determine the prevalence of anatomical variations of the superior mesenteric artery (SMA) and its branches in relation to the superior mesenteric vein (SMV). Secondary outcome was to evaluate the association between these anatomical variations and sex and ethnicity of the patients. Design: Cross-sectional study. Material and methods: Two hundred twenty-fivepatients with right colon cancer diagnosed between January 2017 and December 2020 were included. Two independent radiologists described the vascular anatomy of computed tomography scans. The population was divided into 2 groups and subdivided into 6 groups (1a-c, 2a-c), according to the relationship of the SMA and its branches with the SMV. Results: The ileocolic artery was constant, crossing the SMV posteriorly in 58.7% of the cases. The right colic artery, present in 39.6% of the patients, crossed the SMV on its anterior aspect in 95.5% of the cases. The most frequent subgroup variant was 2a followed by 1a (36.4 and 24%, respectively). No association was found between anatomical variants and gender or ethnic origin. Conclusions: The anatomical variations of the SMA and its branches are common, with no predominant pattern. There was no association between anatomical variations and gender or ethnic origin in our cohort. Preoperative evaluation of these variations by computed tomography angi-ography is useful to avoid vascular injuries during CME-D3. (AU)

A multi-centre randomized controlled trial investigating Consolidation Chemotherapy with and without oxaliplatin in distal rectal cancer and Watch & Wait.

BACKGROUND: Neoadjuvant chemoradiation(nCRT) has been considered the preferred initial treatment strategy for distal rectal cancer. Advantages of this approach include improved local control after radical surgery but also the opportunity for organ preserving strategies (Watch and Wait-WW). Consolidation chemotherapy(cCT) regimens using fluoropyrimidine-based with or without oxalipatin following nCRT have demonstrated to increase complete response and organ preservation rates among these patients. However, the benefit of adding oxaliplatin to cCT compared to fluoropirimidine alone regimens in terms of primary tumor response remains unclear. Since oxalipatin-treatment may be associated with considerable toxicity, it becomes imperative to understand the benefit of its incorporation into standard cCT regimens in terms of primary tumor response. The aim of the present trial is to compare the outcomes of 2 different cCT regimens following nCRT (fluoropyrimidine-alone versus fluoropyrimidine + oxaliplatin) for patients with distal rectal cancer. METHODS: In this multi-centre study, patients with magnetic resonance-defined distal rectal tumors will be randomized on a 1:1 ratio to receive long-course chemoradiation (54 Gy) followed by cCT with fluoropyrimidine alone versus fluoropyrimidine + oxaliplatin. Magnetic resonance(MR) will be analyzed centrally prior to patient inclusion and randomization. mrT2-3N0-1 tumor located no more than 1 cm above the anorectal ring determined by sagittal views on MR will be eligible for the study. Tumor response will be assessed after 12 weeks from radiotherapy(RT) completion. Patients with clinical complete response (clinical, endoscopic and radiological) may be enrolled in an organ-preservation program(WW). The primary endpoint of this trial is decision to organ-preservation surveillance (WW) at 18 weeks from RT completion. Secondary endpoints are 3-year surgery-free survival, TME-free survival, distant metastases-free survival, local regrowth-free survival and colostomy-free survival. DISCUSSION: Long-course nCRT with cCT is associated with improved complete response rates and may be a very attractive alternative to increase the chances for organ-preservation strategies. Fluoropyrimidine-based cCT with or without oxaliplatin has never been investigated in the setting of a randomized trial to compare clinical response rates and the possibility of organ-preservation. The outcomes of this study may significantly impact clinical practice of patients with distal rectal cancer interested in organ-preservation. TRIAL REGISTRATION: www. CLINICALTRIALS: gov NCT05000697; registered on August 11th, 2021.

Long-term outcomes and risk factors for diverticulitis recurrence after a successful laparoscopic peritoneal lavage in Hinchey III peritonitis.

PURPOSE: Recently, treatment of Hinchey III diverticulitis by laparoscopic peritoneal lavage has been questioned. Moreover, long-term outcomes have been scarcely reported. Primary outcome was to determine the recurrence rate of diverticulitis after a successful laparoscopic peritoneal lavage in Hinchey III diverticulitis. Secondary outcomes were identification of associated risk factors for recurrence and elective sigmoidectomy rate. METHODS: A retrospective cohort study in a tertiary referral center was performed. Patients with Hinchey III diverticulitis who underwent a successful laparoscopic peritoneal lavage between June 2006 and December 2019 were eligible. Diverticulitis recurrence was analyzed according to the Kaplan-Meier and log-rank test, censoring for death, loss of follow-up, or elective sigmoid resection in the absence of recurrence. Risk factors for recurrence were identified using Cox regression analysis. RESULTS: Sixty-nine patients had a successful laparoscopic peritoneal lavage (mean age: 63 years; 53.6% women). Four patients had an elective sigmoid resection without recurrences. Recurrence rate was 42% (n = 29) after a median follow-up of 63 months. The cumulative global recurrence at 1, 3, and 5 years was 30% (95% CI, 20-43%), 37.5% (95% CI, 27-51%), and 48.9% (95% CI, 36-64%), respectively. Smoking (HR, 2.87; 95% CI, 1.22-6.5; p = 0.016) and episodes of diverticulitis prior to laparoscopic peritoneal lavage (HR, 5.2; 95% CI, 2.11-12.81; p < 0.001) were independently associated with an increased risk of recurrence. CONCLUSIONS: Diverticulitis recurrence after a successful laparoscopic peritoneal lavage is high, decreasing after the first year of follow-up. Smoking and previous episodes of acute diverticulitis independently increase the risk of new episodes of diverticulitis.

Factors affecting local regrowth after watch and wait for patients with a clinical complete response following chemoradiotherapy in rectal cancer (InterCoRe consortium): an individual participant data meta-analysis.

BACKGROUND: In patients with rectal cancer who achieve clinical complete response after neoadjuvant chemoradiotherapy, watch and wait is a novel management strategy with potential to avoid major surgery. Study-level meta-analyses have reported wide variation in the proportion of patients with local regrowth. We did an individual participant data meta-analysis to investigate factors affecting occurrence of local regrowth. METHODS: We updated search results of a recent systematic review by searching MEDLINE and Embase from Jan 1, 2016, to May 5, 2017, and used expert knowledge to identify published studies reporting on local regrowth in patients with rectal cancer managed by watch and wait after clinical complete response to neoadjuvant chemoradiotherapy. We restricted studies to those that defined clinical complete response using criteria equivalent to São Paulo benchmarks (ie, absence of residual ulceration, stenosis, or mass within the rectum on clinical and endoscopic examination). The primary outcome was 2-year cumulative incidence of local regrowth, estimated with a two-stage random-effects individual participant data meta-analysis. We assessed the effects of clinical and treatment factors using Cox frailty models, expressed as hazard ratios (HRs). From these models, we derived percentage differences in mean θ as an approximation of the effect of measured covariates on between-centre heterogeneity. This study is registered with PROSPERO, number CRD42017070934. FINDINGS: We obtained individual participant data from 11 studies, including 602 patients enrolled between March 11, 1990, and Feb 13, 2017, with a median follow-up of 37·6 months (IQR 25·0-58·7). Ten of the 11 datasets were judged to be at low risk of bias. 2-year cumulative incidence of local regrowth was 21·4% (random-effects 95% CI 15·3-27·6), with high levels of between-study heterogeneity (I2=61%). We noted wide between-centre variation in patient, tumour, and treatment characteristics. We found some evidence that increasing cT stage was associated with increased risk of local regrowth (random-effects HR per cT stage 1·40, 95% CI 1·00-1·94; ptrend=0·048). In a subgroup of 459 patients managed after 2008 (when pretreatment staging by MRI became standard), 2-year cumulative incidence of local regrowth was 19% (95% CI 13-28) for stage cT1 and cT2 tumours, 31% (26-37) for cT3, and 37% (21-60) for cT4 (random-effects HR per cT stage 1·50, random-effects 95% CI 1·03-2·17; ptrend=0·0330). We estimated that measured factors contributed 4·8-45·3% of observed between-centre heterogeneity. INTERPRETATION: In patients with rectal cancer and clinical complete response after chemoradiotherapy managed by watch and wait, we found some evidence that increasing cT stage predicts for local regrowth. These data will inform clinician-patient decision making in this setting. Research is needed to determine other predictors of a sustained clinical complete response. FUNDING: None.

Right versus left laparoscopic colectomy for colon cancer: does side make any difference?

PURPOSE: To compare the intraoperative and postoperative outcomes between right laparoscopic colectomy (RLC) and left laparoscopic colectomy (LLC) for colon cancer. METHOD: Patients who underwent elective RLC or LLC for colon cancer between January 2004 and December 2014 were identified and elected for a retrospective analysis. Primary outcomes were technical difficulty (including operative time, intraoperative complications, and conversion rate) and postoperative outcome (including postoperative complications, length of hospital stay, reinterventions, readmissions, and mortality). RESULTS: A total of 547 patients (mean age: 68.5 years old; 48.4% males) were analyzed. The RLC group had a higher mean age (71 vs 65; p < 0.001), ASA 3/4 grade (36 vs 26%; p = 0.02), and comorbidity rate (61 vs 48%, p = 0.003). Regarding technical difficulty, no difference was found between the groups in intraoperative complications (4.1 vs 5.9%; p = 0.34) or conversion rate (6.2 vs 3.9%, p = 0.24). Mean operative time was significantly shorter for RLC (162 vs 185 min, p < 0.001). Regarding postoperative outcome, the RLC group had a higher overall morbidity (20.5 vs 13.3%, p = 0.03), ileus (10.6 vs 2.4%, p < 0.001), and a longer hospital stay (4.7 vs 3.9 days, p = 0.003), with no differences regarding reoperations, readmissions, or mortality. The multivariate analysis showed that RLC were independently associated with a longer operative time and postoperative ileus. CONCLUSIONS: RLC for colon cancer was independently associated with a shorter operative time, an increased risk of ileus, and a longer hospital stay than left laparoscopic colectomy in high-volume centers.

Laparoscopic peritoneal lavage for Hinchey III diverticulitis: is it as effective as it is applicable?

BACKGROUND: Over the past few years, the laparoscopic peritoneal lavage has emerged as a therapeutic alternative to standard resection procedures. However, its effectiveness and applicability remain debatable. OBJECTIVE: The aim of this study was to assess laparoscopic lavage in controlling abdominal sepsis secondary to purulent peritonitis. DESIGN: This study was conducted as a retrospective analysis of prospectively collected data. SETTING: This study was conducted at a single tertiary care institution. PATIENTS: Patients requiring emergency surgery for perforated diverticulitis and generalized peritonitis between June 2006 and June 2013 were identified from a prospective database. Laparoscopic assessment was considered in all of the hemodynamically stable patients, and laparoscopic lavage was performed according to intraoperative strict criteria. MAIN OUTCOME MEASURES: Primary outcomes were the effectiveness and applicability of laparoscopic lavage. Secondarily, feasibility, morbidity, and mortality were also assessed. RESULTS: Seventy-five patients required emergency surgery for generalized peritonitis secondary to perforated diverticulitis. Forty-six patients who underwent laparoscopy presented a purulent generalized (Hinchey III) peritonitis and were examined under the intention-to-treat basis to perform a laparoscopic lavage. Thirty-two patients (70.0%; 95% CI 56.2-82.7) had no previous episodes of diverticulitis. Thirty-six patients (78.0%; 95% CI 66.3-90.1) had free air on a CT scan. The conversion rate was 4% (95% CI 0-10). The feasibility of the method was 96.0% (95% CI 90.4-100), and its applicability was 59.0% (95% CI 44.8-73.2). Median operative time was 89 minutes (range, 40-200 minutes). Postoperative morbidity was 24.0% (95% CI 11.7-36.3), and the mortality rate was 0%. We registered 5 failures, and all of them underwent reoperation. The effectiveness of the procedure was 85% (95% CI 76-93). LIMITATIONS: This was a single-institution retrospective study. CONCLUSIONS: The effectiveness of laparoscopic lavage seems to be high. Although its applicability is lower, it could be applied in more than half of patients requiring emergency surgery. This alternative strategy should be considered when laparoscopic assessment reveals Hinchey III diverticulitis.

Laparoscopic colorectal resections: a simple predictor model and a stratification risk for conversion to open surgery.

BACKGROUND: The advantages associated with the laparoscopic approach are lost when conversion is required. Available predictive models have failed to show external validation. Body surface area is a recently described risk factor not included in these models. OBJECTIVE: The aim of this study was to develop a clinical rule including body surface area for predicting conversion in patients undergoing elective laparoscopic colorectal surgery. DESIGN: This was a prospective cohort study. SETTING: This study was conducted at a single large tertiary care institution. PATIENTS: Nine hundred sixteen patients (mean age, 63.9; range, 14-91 years; 53.2% female) who underwent surgery between January 2004 and August 2011 were identified from a prospective database. MAIN OUTCOME MEASURES: Conversion rate was analyzed related to age, sex, obesity, disease location (colon vs rectum), type of disease (neoplastic vs nonneoplastic), history of previous surgery, and body surface area. A predictive model for conversion was developed with the use of logistic regression to identify independently associated variables, and a simple clinical prediction rule was derived. Internal validation of the model was performed by using bootstrapping. RESULTS: The conversion rate was 9.9% (91/916). Rectal disease, large patient size, and male sex were independently associated with higher odds of conversion (OR, 2.28 95%CI, 1.47-3.46]), 1.88 [1.1-3.44], and 1.87 [1.04-3.24]). The prediction rule identified 3 risk groups: low risk (women and nonlarge males), average risk (large males with colon disease), and high risk (large males with rectal disease). Conversion rates among these groups were 5.7%, 11.3%, and 27.8% (p < 0.001). Compared with the low-risk group, ORs for average- and high-risk groups were 2.17 (1.30-3.62, p = 0.004) and 6.38 (3.57-11.4, p < 0.0001). LIMITATIONS: The study was limited by the lack of external validation. CONCLUSION: This predictive model, including body surface area, stratifies patients with different conversion risks and may help to inform patients, to select cases in the early learning curve, and to evaluate the standard of care. However, this prediction rule needs to be externally validated in other samples (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A137).

El área de superficie corporal: un factor predictor de conversión en cirugía colorrectal laparoscópica

Antecedentes: El área de superficie corporal es una medida usada en el entorno clínico. Su impacto en la cirugía colorrectal laparoscópica no ha sido estudiado previamente. Objetivo: Evaluar el impacto de la superficie corporal sobre la tasa de conversión y el tiempo operatorio en cirugía laparoscópica. Diseño: Análisis retrospectivo de datos recogidos prospectivamente. Marco: Una sola institución de atención terciaria. Pacientes: Fueron identificados 916 pacientes consecutivos operados entre enero de 2004 y agosto de 2011, incluidos en una base de datos completada en forma prospectiva. Principales medidas de resultado: Se analizaron la tasa de conversión y el tiempo operatorio laparoscópico en relación a la edad, el género, la obesidad, la localización de la enfermedad (colon vs recto), el tipo de enfermedad (neoplásica vs no neoplásica), el antecedente de cirugías previas, y la superficie corporal; el área de superficie corporal se calculó mediante la fórmula de Mosteller. El área de superficie corporal se analizó utilizando la mediana, y cuartilos con valores de corte de 1.6; 1.8 y 2.0. Se utilizó la regresión logística para analizar la asociación entre el área de superficie corporal y la tasa de conversión, ajustada por diferentes factores. Se investigó la interacción entre la superficie corporal y el índice de masa corporal, pero no fue constatada. Resultados: La tasa de conversión global fue del 10%. La mediana del área de superficie corporal fue de 1.84 m² (rango: 1.14- 2.53). Las tasas de conversión de los cuartiles 1, 2, 3 y 4 fueron: 4.4%, 8.3%, 12.7% y 14.8%, respectivamente, p=0.001. Los pacientes con superficie corporal > 1.8 m²(N = 503) tuvieron una tasa de conversión más alta que los de superficie corporal < 1.8 m²(N=413) [13.8% vs 6.3%, respectivamente, OR: 2.35 (IC 95%: 1.45-3.86, p=0.0001)]. El análisis multivariado mostró que el área de superficie corporal > 1.8m² se asoció a la conversión (OR: 2, 95% Cl: 1.1-3.7, p=0.023) después de ajustar por sexo, edad, obesidad, localización de la patología (recto vs colon), tipo de abordaje laparoscópico y antecedente de cirugías previas. Limitación: se trata de un estudio retrospectivo realizado en una sola institución. Conclusión: El área de superficie corporal es un buen predictor de la conversión; debe ser incluido como parte de los futuros estudios sobre los resultados de la cirugía colorrectal laparoscópica, como información a los pacientes, cuando se seleccionan casos al inicio de la curva de aprendizaje, y al determinar el estándar de calidad de atención.

Background: Body surface área is a measurement used in clinical settings. Its impact on laparoscopic colorectal surgery has not been previously studied. Objective:To assess the impact of body surface área on conversión rate. Design: Retrospective analysis of prospectively collected data. Setting: Single tertiary care institution. Patients: 916 consecutive patients operated on between January 2004 and August 2011 were identified from a prospectively datábase. Main outcome measures: Conversión rate was analyzed related to age, gender, obesity, disease location (colon vs. rectum), type of disease (neoplastic vs. non-neoplastic), history of previous surgery, and body surface área; body surface área was calculated by Mosteller formula. Body surface área was analyzed using median and quartiles cut off valúes (1.6, 1.8 and 2.0). Logistic regression was used to analyze the association between body surface área and conversión, adjusting for different confounders. Interaction between body surface área and body mass Índex was checked and not found. Results: Overall conversión rate was 10%. Median body surface área was 1.84 (range: 1.14-2.53).Conversión rates for quartiles 1, 2, 3 and 4 were: 4.4%, 8.3%, 12.7%, and 14.8%, respectively, p = 0.001. Patients with body surface área > 1.8 (N=503) had a higher conversión rate than those with body surface área < 1.8 (N=413) [13.8% vs 6.3%, respectively, OR: 2.35 (95% Cl: 1.45-3.86; p=0.0001)j. Multivariate analysis showed that body surface área > 1.8 was associated with conversión (OR: 2, 95% Cl: 1.1-3.7, p=0.023) after adjusting for gender, age, and previous surgery. ROC analysis of body surface área showed an área under the curve of 0.62. Body surface área > 1.8 had a sensitivity and specificity of 76% and 48% respectively. Limitation: This was a single institution retrospective study. Conclusión: Body surface área is a good predictor for conversión and should be included as part of future studies on outcomes for laparoscopic colorectal surgery.

El área de superficie corporal: un factor predictor de conversión en cirugía colorrectal laparoscópica

Antecedentes: El área de superficie corporal es una medida usada en el entorno clínico. Su impacto en la cirugía colorrectal laparoscópica no ha sido estudiado previamente. Objetivo: Evaluar el impacto de la superficie corporal sobre la tasa de conversión y el tiempo operatorio en cirugía laparoscópica. Diseño: Análisis retrospectivo de datos recogidos prospectivamente. Marco: Una sola institución de atención terciaria. Pacientes: Fueron identificados 916 pacientes consecutivos operados entre enero de 2004 y agosto de 2011, incluidos en una base de datos completada en forma prospectiva. Principales medidas de resultado: Se analizaron la tasa de conversión y el tiempo operatorio laparoscópico en relación a la edad, el género, la obesidad, la localización de la enfermedad (colon vs recto), el tipo de enfermedad (neoplásica vs no neoplásica), el antecedente de cirugías previas, y la superficie corporal; el área de superficie corporal se calculó mediante la fórmula de Mosteller. El área de superficie corporal se analizó utilizando la mediana, y cuartilos con valores de corte de 1.6; 1.8 y 2.0. Se utilizó la regresión logística para analizar la asociación entre el área de superficie corporal y la tasa de conversión, ajustada por diferentes factores. Se investigó la interacción entre la superficie corporal y el índice de masa corporal, pero no fue constatada. Resultados: La tasa de conversión global fue del 10%. La mediana del área de superficie corporal fue de 1.84 m² (rango: 1.14- 2.53). Las tasas de conversión de los cuartiles 1, 2, 3 y 4 fueron: 4.4%, 8.3%, 12.7% y 14.8%, respectivamente, p=0.001. Los pacientes con superficie corporal > 1.8 m²(N = 503) tuvieron una tasa de conversión más alta que los de superficie corporal < 1.8 m²(N=413) [13.8% vs 6.3%, respectivamente, OR: 2.35 (IC 95%: 1.45-3.86, p=0.0001)]. El análisis multivariado mostró que el área de superficie corporal > 1.8m² se asoció a la conversión (OR: 2, 95% Cl: 1.1-3.7, p=0.023) después de ajustar por sexo, edad, obesidad, localización de la patología (recto vs colon), tipo de abordaje laparoscópico y antecedente de cirugías previas. Limitación: se trata de un estudio retrospectivo realizado en una sola institución. Conclusión: El área de superficie corporal es un buen predictor de la conversión; debe ser incluido como parte de los futuros estudios sobre los resultados de la cirugía colorrectal laparoscópica, como información a los pacientes, cuando se seleccionan casos al inicio de la curva de aprendizaje, y al determinar el estándar de calidad de atención.(AU)

Background: Body surface área is a measurement used in clinical settings. Its impact on laparoscopic colorectal surgery has not been previously studied. Objective:To assess the impact of body surface área on conversión rate. Design: Retrospective analysis of prospectively collected data. Setting: Single tertiary care institution. Patients: 916 consecutive patients operated on between January 2004 and August 2011 were identified from a prospectively datábase. Main outcome measures: Conversión rate was analyzed related to age, gender, obesity, disease location (colon vs. rectum), type of disease (neoplastic vs. non-neoplastic), history of previous surgery, and body surface área; body surface área was calculated by Mosteller formula. Body surface área was analyzed using median and quartiles cut off valúes (1.6, 1.8 and 2.0). Logistic regression was used to analyze the association between body surface área and conversión, adjusting for different confounders. Interaction between body surface área and body mass Index was checked and not found. Results: Overall conversión rate was 10%. Median body surface área was 1.84 (range: 1.14-2.53).Conversión rates for quartiles 1, 2, 3 and 4 were: 4.4%, 8.3%, 12.7%, and 14.8%, respectively, p = 0.001. Patients with body surface área > 1.8 (N=503) had a higher conversión rate than those with body surface área < 1.8 (N=413) [13.8% vs 6.3%, respectively, OR: 2.35 (95% Cl: 1.45-3.86; p=0.0001)j. Multivariate analysis showed that body surface área > 1.8 was associated with conversión (OR: 2, 95% Cl: 1.1-3.7, p=0.023) after adjusting for gender, age, and previous surgery. ROC analysis of body surface área showed an área under the curve of 0.62. Body surface área > 1.8 had a sensitivity and specificity of 76% and 48% respectively. Limitation: This was a single institution retrospective study. Conclusión: Body surface área is a good predictor for conversión and should be included as part of future studies on outcomes for laparoscopic colorectal surgery.(AU)

Body surface area: a new predictor factor for conversion and prolonged operative time in laparoscopic colorectal surgery.

BACKGROUND: Body surface area is a measurement of body size used in clinical settings. Its impact on laparoscopic colorectal surgery has not been previously studied. OBJECTIVE: The aim of this study was to assess the impact of body surface area on the conversion rate and laparoscopic operative time. DESIGN: This study was conducted as a retrospective analysis of prospectively collected data. SETTING: This study was conducted at a single tertiary care institution. PATIENTS: Nine hundred sixteen consecutive patients operated on between January 2004 and August 2011 were identified from a prospective database. MAIN OUTCOME MEASURES: Conversion rate and laparoscopic operative time were analyzed related to age, sex, obesity, disease location (colon vs rectum), type of disease (neoplastic vs nonneoplastic), history of previous surgery, and body surface area; body surface area was calculated by the Mosteller formula. Body surface area was analyzed by the use of median and quartile cutoff values (1.6, 1.8, and 2.0). Multivariate models were adjusted for different confounders. Interaction between body surface area and BMI was ruled out. RESULTS: The conversion rate was 10%. Conversion rates for quartiles 1, 2, 3, and 4 were 4.4%, 8.3%, 12.7%, and 14.8%, p = 0.001. Patients with body surface area ≥ 1.8 had a higher conversion rate than those with body surface area <1.8 (13.9% vs 5.3%, OR: 2.35 (95% CI: 1.45-3.86; p = 0.0001)). Multivariate analysis showed that body surface area ≥ 1.8 was associated with conversion (OR: 2, 95% CI: 1.1-3.7, p = 0.02) and a longer operative time after adjusting for sex, age, obesity, disease location (rectum vs colon), and type of laparoscopic approach. LIMITATION: This was a single-institution retrospective study. CONCLUSION: Body surface area is a predictor for conversion and longer laparoscopic operative time. It should be considered when informing patients, selecting cases in the early learning curve, and assessing standard of care.

Resección total del mesorrecto laparoscópica con conservación esfinteriana: resultados oncológicos iniciales / Laparoscopic total mesorectal excision with sphincter preservation: initial oncologic outcomes

Objetivo: Evaluar los resultados oncológicos iniciales con la Resección Total del Mesorrecto (RTM) laparoscópica con conservación esfinteriana en pacientes portadores de tumores de recto medio e inferior. Material y Método: Entre Marzo de 2005 y Septiembre de 2008 se operaron por vía laparoscópica 72 pacientes portadores de cáncer de recto y fueron ingresados prospectivamente en una base de datos. Se analizaron aquellos pacientes con tumores de recto medio e inferior en los que se realizó una RTM laparoscópica con conservación esfinteriana. Se evaluaron variables clínicas. anatomopatológicas y oncológicas. Resultados: 42 pacientes (58 por ciento) presentaron tumores de recto medio e inferior en los que se realizó una RTM con conservación esfinteriana. Diez pacientes (23.8 por ciento) recibieron quimio-radioterapia preoperatoria. La altura media de estos tumores fue de 7.9 cm (r: 4-11) y la altura de la anastomosis fue 4.9 cm. Ningún paciente presentó compromiso del margen radial ni distal (media de 12 mm y 20 mm respectivamente). La morbilidad postoperatoria fue del 26 por ciento. Cuatro pacientes debieron ser reoperados (9.5 por ciento). No se registró mortalidad a 30 días. Con una media de seguimiento de 27.4 meses (r: 10-48), la sobrevida global y libre de enfermedad actuarial a 3 años fue de 88 y 84 por ciento respectivamente, y la tasa de recurrencia local fue 2.3 por ciento (n = 1). Conclusión: La RTM laparoscópica con conservación esfinteriana puede ser realizada sin comprometer el margen radial ni distal, con un bajo índice de recurrencia local y una sobrevida elevada.

Objective: To assess the initial oncologic outcomes of laparoscopic total mesorectal excision (TME) with sphincter preservation in patients with neoplasms located in the middle and low rectum. Methods: Between March 2005 and September 2008. 72 patients with diagnosis of rectal cancer were operated on by laparoscopic surgery and included in a prospective database. Patients with middle and low rectal cancer who underwent laparoscopic TME with sphincter preservation, were analyzed. Clinical, pathological and oncological data were reviewed. Results: 42 patients (58 per cent) presented with middle and low rectal cancer who underwent laparoscopic TME with sphincter preservation. Ten patients (23.8 per cent) received preoperative chemoradiation. Mean tumor height was 7.9 cm (r: 4-11) and anastomotic height was 4.9 cm. Neither circumferential margin nor distal margin was involved (mean distance of 12mm and 20 mm respectively). Thirty-day morbidity was 26 per cent. Four patients required reoperation (9.5 per cent). There was no 30-day mortality. The actuarial 3-year overall survival and disease-free survival were 88 and 84 per cent respectively and local recurrence rate was 2.3 per cent (n = 1) with a mean follow-up time of 27.4 month (r: 10-48). Conclusions: Laparoscopic TME with sphincter preservation can be performed without involve the circumferential and distal margin, with a low local recurrence rate and a high survival.

Lymph node ratio as prognosis factor for colon cancer treated by colorectal surgeons.

PURPOSE: This study was designed to assess the prognostic value of the lymph node ratio in patients with colon cancer treated by colorectal specialists. METHODS: Three hundred and sixty-two Stage III consecutive cases were analyzed based on quartiles: lymph node ratio 1 (>0 and <0.06); lymph node ratio 2 (between 0.06 and 0.12); lymph node ratio 3 (>0.12 and <0.25); lymph node ratio 4 (>or=0.25). RESULTS: Disease-free survival rates were: lymph node ratio 1, 75.5%; lymph node ratio 2, 74.2%; lymph node ratio 3, 73.2%; and lymph node ratio 4, 40.1%. Similar differences were observed for cancer-specific and overall survival rates. Cases with lymph node ratio >or=0.25 had higher hazard ratios than cases with lymph node ratio <0.25 in terms of disease-free survival (2.8, P < 0.001), cancer-specific survival (3.1, P = 0.0001), and overall survival (2.2, P = 0.0001). The hazard ratio of cases with up to three positive nodes and lymph node ratios >or=0.25 was higher than that of cases with up to three positive nodes and lymph node ratios <0.25 in terms of disease-free survival (3.1, P = 0.003), cancer-specific survival (3.5, P = 0.002), and overall survival (2.4, P = 0.02). Similar differences were found for cases with more than three positive nodes. Lymph node ratio, but not number of positive nodes, had independent prognostic value in multivariate analysis. No interaction between these two variables was found. CONCLUSION: A lymph node ratio >or=0.25 was an independent prognostic factor in Stage III colon adenocarcinoma regardless of the number positive nodes. It modified outcomes predicted by the current staging system.

Apendicectomía laparoscópica. Evaluación de nuestra experiencia / Laparoscopic appendectomy. Evaluation of our experience

Antecedentes: desde la aparición de la apendicectomía laparoscópica en el año 1982, se han publicado numerosos trabajos en la literatura mundial evaluando la utilidad y los resultados del método. Objetivo: analizar la experiencia de un Hospital Privado de Comunidad en el tratamiento de la apendicitis aguda por vía laparoscópica. Diseño: estudio restrospectivo de observación clínica. Población: se analizaron las historias clínicas de todos los pacientes sometidos a apendicectomía laparoscópica (AL) durante el período comprendido entre el 1 de enero de de 1994 y el 31 de diciembre de 1998, que sumaron un total de 96. Método: se evaluó principalmente la técnica, las complicaciones intra y postoperatorias y los resultados alejados. Para el tratamiento del meso y de la base apendicular se emplearon endoclips y doble lazo preformado de polipropileno respectivamente. Resultados: hubo 66 apendicitis agudas, 27 peritonitis y 3 apéndices normales. En el 95 por ciento de los casos se utilizaron tres trocares. Cuatro cirugías debieron ser convertidas. Se resgistraron 20 complicaciones intraoperatorias, de las cuales ninguna fue motivo de conversión. De las complicaciones postoperatorias la más importante fue el absceso intraabdominal, obligando en un caso a reintervenir al paciente. El 87.5 por ciento de las cirugías fueron realizadas por médicos residentes. El tiempo operatorio promedio fue de 102.2 minutos, y la estadía hospitalaria fue de 2.6 días para la apendicitis aguda y de 3.7 para la peritonitis. Conclusión: la AL resultó ser un método seguro, realizable con instrumental básico y de gran utilidad para la formación del residente en cirugía laparoscópica

Apendicectomía laparoscópica. Evaluación de nuestra experiencia / Laparoscopic appendectomy. Evaluation of our experience

Antecedentes: desde la aparición de la apendicectomía laparoscópica en el año 1982, se han publicado numerosos trabajos en la literatura mundial evaluando la utilidad y los resultados del método. Objetivo: analizar la experiencia de un Hospital Privado de Comunidad en el tratamiento de la apendicitis aguda por vía laparoscópica. Diseño: estudio restrospectivo de observación clínica. Población: se analizaron las historias clínicas de todos los pacientes sometidos a apendicectomía laparoscópica (AL) durante el período comprendido entre el 1 de enero de de 1994 y el 31 de diciembre de 1998, que sumaron un total de 96. Método: se evaluó principalmente la técnica, las complicaciones intra y postoperatorias y los resultados alejados. Para el tratamiento del meso y de la base apendicular se emplearon endoclips y doble lazo preformado de polipropileno respectivamente. Resultados: hubo 66 apendicitis agudas, 27 peritonitis y 3 apéndices normales. En el 95 por ciento de los casos se utilizaron tres trocares. Cuatro cirugías debieron ser convertidas. Se resgistraron 20 complicaciones intraoperatorias, de las cuales ninguna fue motivo de conversión. De las complicaciones postoperatorias la más importante fue el absceso intraabdominal, obligando en un caso a reintervenir al paciente. El 87.5 por ciento de las cirugías fueron realizadas por médicos residentes. El tiempo operatorio promedio fue de 102.2 minutos, y la estadía hospitalaria fue de 2.6 días para la apendicitis aguda y de 3.7 para la peritonitis. Conclusión: la AL resultó ser un método seguro, realizable con instrumental básico y de gran utilidad para la formación del residente en cirugía laparoscópica