Síndrome de resección anterior baja y su relación con la calidad de vida: aplicación de cuestionario EuroQol-5 / Low anterior resection syndrome and quality of life: application of EuroQol-5 questionnaire

Resumen Introducción: Las cirugías con preservación de esfínter tienen como consecuencia el desarrollo de una disfunción defecatoria con diferentes grados, la cual es conocida como síndrome de resección anterior baja (LARS) y es medida con el cuestionario LARS Score. Objetivo: Determinar la asociación del cuestionario EuroQol-5 (calidad de vida) con los diferentes grados de LARS Score. Materiales y Método: Estudio de tipo transversal, aplicando el cuestionario LARS Score y EuroQol-5 a pacientes operados por cáncer de recto medio y bajo, durante el periodo 2004-2017. Se realiza análisis demográfico y del tipo de cirugía. Para determinar asociaciones entre variables se utilizan diferentes pruebas estadísticas, considerando significativo un valor de p < 0,05. Resultados: Se encuestó a 54 pacientes, 62,16% hombres, promedio de edad 58,44 años, el 37,03% presentó LARS Mayor. Los índices promedio de calidad de vida para pacientes No LARS es 0,75, para LARS Menor es 0,69 y para LARS Mayor es 0,61, la diferencia entre índices presenta un valor p = 0,246. 46,3% presenta problemas en actividades habituales. LARS Mayor presenta un Odd-Ratio de 3,8 y 4,7 para dolor/malestar y angustia/depresión respectivamente. 70% de los pacientes con LARS Mayor presentaron resección total del mesorrecto (TME) y el 45% corresponde a menores de 65 años. Discusión: No existe diferencia estadísticamente significativa entre los índices de calidad de vida según LARS Score. LARS Mayor tiene mayor posibilidad de desarrollar algún grado de dolor/malestar y angustia/depresión. El porcentaje de LARS Mayor es acorde a lo publicado y la TME es uno de los factores de mayor impacto en el desarrollo de LARS. Conclusiones: El LARS Score se relaciona de manera no significativa con el índice de calidad de vida entregado por el cuestionario EuroQol-5D, existiendo una tendencia a disminuir la calidad de vida a medida que empeora el LARS.

Introduction: Sphincter-sparing surgeries result in the development of a defecatory dysfunction with different degrees, which is known as low anterior resection syndrome (LARS) and is measured with the LARS Score questionnaire. Objective: To determine the association of the EuroQol-5 questionnaire with the different degrees of LARS Score. Materials and Method: Crosssectional study, applying the LARS Score and EuroQol-5 questionnaire to patients operated with low and middle rectal cancer, during the period 2004-2017. Demographic analysis and type of surgery are performed. Different statistical tests are used to determine associations between variables, considering a significant p value < 0.05. Results: 54 patients were surveyed, 62.16% men, mean age 58.44 years, 37.03% presented Mayor-LARS. The average quality of life indices for Non-LARS patients is 0.75, for Minor-LARS is 0.69 and for Mayor-LARS is 0.61, the difference between indices presents a p value = 0.246. 46.3% present problems in habitual activities. LARS Mayor presents an Odd-Ratio of 3.8 and 4.7 for pain/discomfort and anguish/depression respectively. 70% of patients with LARS Mayor presented SMT and 45% corresponded to those under 65 years of age. Discussion: There is no statistically significant difference between the quality of life indices according to the LARS Score. Mayor-LARS is more likely to develop some degree of Pain/Discomfort and anguish/depression. The percentage of Mayor-LARS is according to what has been published and the TME is one of the factors with the greatest impact on the development of LARS. Conclusion: The LARS Score is non-significantly related to the quality of life index provided by the EuroQol-5D questionnaire, and there is a tendency to decrease quality of life as the LARS worsens.

Síndrome de resección anterior baja en pacientes con cáncer de recto medio e inferior ¿Qué más podemos hacer? / Low anterior resection syndrome in patients with medium and low rectal cancer. What else can we do?

Resumen Durante las últimas décadas los avances en técnicas quirúrgicas, radioterapia y quimioterapia han logrado de forma significativa aumentar la sobrevida y disminuir la recidiva local en el cáncer de recto evitando una colostomía definitiva; sin embargo, este trascendental progreso médico no ha ido acompañado de una mejoría en los resultados funcionales de los pacientes sometidos a una cirugía conservadora de esfínter, siendo el conjunto de síntomas defecatorios posterior a la resección rectal, conocido como síndrome de resección anterior baja (LARS), una secuela prácticamente inevitable, que generalmente se asocia a disfunción sexual, urinaria, dolor crónico, altos costos en rehabilitación y control sintomático, además de una alteración importante en la calidad de vida. En este artículo presentamos una revisión completa y actualizada de las características clínicas y alternativas de tratamiento del LARS, finalizando con una propuesta de manejo integral multidisciplinario que destaca la importancia de la prehabilitación, evaluación objetiva de los síntomas, educación e información adecuada del paciente y su familia, además del trabajo en equipo en unidades especializadas de rehabilitación de piso pélvico, requisito fundamental a la hora de manejar adecuadamente esta patología.

During the last decades, advances in surgical techniques, radiotherapy and chemotherapy have significantly increased survival and reduced local recurrence in rectal cancer, avoiding a definitive colostomy. However, this transcendental medical progress has not been accompanied by an improvement in the functional results of patients after sphincter-preserving rectal resection, being the set of defecatory symptoms after rectal resection, known as low anterior resection syndrome (LARS), a practically inevitable sequel, which is usually associated with sexual or urinary dysfunction, chronic pain, high costs and an important alteration in the quality of life. In this article, we will present a complete and updated review of the clinical and alternative characteristics of LARS treatment, ending with a proposal for multidisciplinary and integral management that highlights the importance of prehabilitation, objective evaluation of symptoms, education and adequate information of the patient and his family, in addition to teamwork in units specialized in pelvic floor rehabilitation, a fundamental requirement when properly managing this pathology.

Effect of Neoadjuvant Treatment on TRG, Surgical Complications and LARS in Patients with Rectal Cancer / 肿瘤防治研究

Objective To investigate the effects of different neoadjuvant treatments on tumor regression, surgical complications and low anterior resection syndrome (LARS) in patients with rectal cancer. Methods We included 127 patients with rectal cancer receiving neoadjuvant treatments, and they were divided into long-term concurrent chemoradiotherapy group (n=42), short-term radiotherapy+chemotherapy group (n=39) and chemotherapy group (n=46). The pathological results, clinical data and follow-up results were collected. The factors that may affect tumor regression, surgical complications and low anterior resection syndrome after rectal cancer surgery were statistically analyzed and concluded. Results The pCR rates were 28.51%, 10.3% and 8.6% in long-term concurrent chemoradiotherapy group, short-term radiotherapy+chemotherapy group and chemotherapy group, respectively. There were 14 (33.33%), 9 (23.07%) and 10 (21.74%) patients with perioperative complications in three groups, respectively. A total of 91 patients were enrolled in the LARS study. There were 49 (53.84%) cases with LARS symptoms, including 17 (18.68%) cases with severe LARS. In three groups, there were 27 cases (including 13 cases of severe LARS), 12 cases (including 2 cases of severe LARS) and 9 cases (including 2 cases of severe LARS) of LARS symptoms, respectively. Conclusion Three neoadjuvant treatments have good surgical safety. Long-term concurrent chemoradiotherapy and short-term radiotherapy+chemotherapy have advantages in tumor regression, but the former is more likely to cause LARS symptoms and affect the quality of life.Comprehensive consideration is needed in the choice of clinical treatments.

Research progress of different bowel reconstructions for postoperative functional protection during low anterior resections of rectal cancer / 中华胃肠外科杂志

Straight coloanal anastomosis (SCA), colonic J-pouch anastomosis (CJP), transverse coloplasty pouch anastomosis (TCP), and side-to-end anastomosis (SEA) are the most commonly used procedures of bowel reconstructions in the low anterior resections (LAR) of rectal cancer. Different bowel reconstruction procedures greatly affect postoperative bowel function, urinary function and sexual function. SCA is the most traditional procedure. CJP has been studied extensively and well-developed reconstruction method; however, recent studies have shown that CJP has the highest morbidity of complications, so the clinical application of CJP is limited. SEA is not inferior to CJP and SCA in the short-term and long-term defecation function, urination function, and sexual function, with reliable operational safety, so it is expected to become an alternative to SCA and CJP. The research on TCP is lacking, but there are some related clinical trials currently underway, and the results are worth expecting. The improvement and innovation of bowel reconstructions provide a bright prospect for better functional prognosis in patients with rectal cancer.

Síndrome de la resección anterior baja: un alto precio del tratamiento del cáncer de recto / Low anterior resection syndrome: a high cost of rectal cancer treatment

En los últimos 30 años el tratamiento del cáncer del recto ha mejorado significativamente gracias al manejo multidisciplinario y a la introducción del concepto de resección total del mesorrecto (RTM), logrando disminuir las tasas de recidiva local y aumentar la sobrevida. Si bien los avances oncológicos y técnicos en términos de tasas de conservación del esfínter anal son innegables, las secuelas funcionales son significativas, especialmente las relacionadas a la función intestinal, sexual y urinaria. Hasta un 90% de los pacientes sometidos a una RTM refiere secuelas intestinales cuyos síntomas se conocen como el síndrome de la resección anterior baja (SRAB). Recientemente se han diseñado sistemas de valoración específicos que han evidenciado su alta incidencia y prevalencia. En esta revisión se entrega una mirada actualizada de la fisiopatología, factores de riesgo, formas de presentación, evaluación clínica y las distintas alternativas de prevención y tratamiento del SRAB.

In the last 30 years, oncologic outcomes of rectal cancer treatment have been significantly improved due to multimodal management and the introduction of the concept of total mesorectum excision. Although the improvements in oncological treatment and surgical techniques are undeniable, multimodal treatment results in the onset of disorders of the intestinal, sexual and urinary function in a high proportion of these patients. Up to 90% of patients undergoing a low anterior resection refer bowel disorders such as fecal incontinence, urgency, increased frequency and fragmentation of defecation. These elements are included in an entity known as the low anterior resection syndrome and specific assessment tools have been designed recently, evidencing the high incidence and prevalence of this syndrome. In the present review, we update the pathophysiology, risk factors, clinical presentation, evaluation and the alternatives of prevention and treatment of low anterior resection syndrome.

Validation of Portuguese version of the low anterior resection syndrome score / Validação da versão em português do escore da síndrome da ressecção anterior baixa

ABSTRACT Objective: The authors aim to perform a thorough translation with cultural adaptation of the patient reported outcome tool, Low Anterior Resection Syndrome (LARS) Score, to the Portuguese language (LARS-PT) in the Portuguese population with rectal cancer, after proctectomy with anastomosis. Methods: According to the current international recommendations, we designed this study encompassing three main phases: (i) cultural and linguistic validation to European Portuguese; (ii) feasibility and reliability tests of the version obtained in the previous phase; and (iii) validity tests to produce a final version. The questionnaire was completed by 154 patients from six Portuguese Colorectal Cancer Units, and 58 completed it twice. Results: Portuguese version of LARS score showed high construct validity. Regarding the test-retest, the global Intraclass Correlation showed very strong test-retest reliability. Looking at all five items, only items 3 and 5 present a moderate correlation. LARS score was able to discriminate symptoms showing worse quality of life, in patients submitted to preoperative radio and chemotherapy. Conclusions: LARS questionnaire has been properly translated into European Portuguese, demonstrating high construct validity and reliability. This is a precise, reproducible, simple, clear and user-friendly tool for evaluating bowel function in rectal cancer patients after sphincter saving operation.

RESUMO Objetivo: Os autores pretendem fazer uma tradução minuciosa e culturalmente adaptada para a língua portuguesa do escore da Síndrome de Ressecção Anterior Baixa (Low Anterior Resection Syndrome [LARS]), um instrumento de desfecho relatado pelo paciente, na população portuguesa com câncer retal após proctectomia com anastomose. Métodos: De acordo com as recomendações internacionais atuais, o estudo foi projetado abrangendo três fases principais: (i) validação cultural e linguística para o português europeu; (ii) testes de viabilidade e confiabilidade da versão obtida na fase anterior; e (iii) testes de validade para produzir a versão final. O questionário foi preenchido por 154 pacientes de seis unidades portuguesas de câncer colorretal e 58 pacientes completaram duas vezes. Resultados: A versão em português do escore LARS mostrou alta validade de construto. A correlação intra-classe global apresentou confiabilidade muito forte no teste-reteste. Considerando-se todos os cinco itens, apenas os itens 3 e 5 apresentam uma correlação moderada. O escore LARS foi capaz de discriminar sintomas com pior qualidade de vida em pacientes submetidos a radio- e quimioterapia pré-operatória. Conclusões: O questionário LARS foi traduzido corretamente para o português europeu, demonstrando alta validade de construto e confiabilidade. Trata-se de uma ferramenta precisa, reproduzível, simples, clara e fácil de usar para avaliar a função intestinal em pacientes com câncer retal após operações poupando o esfíncter.

Evaluation of defecation function after laparoscopic-assisted transanal total mesorectal excision for low rectal cancer and influencing factors analysis / 中华消化外科杂志

Objective To evaluate the defecation function of patients with low rectal cancer after laparoscopic-assisted transanal total mesorectal excision (TaTME),and analyze the influencing factors.Methods The retrospective case-control study was conducted.The clinicopathological data of 55 patients with low rectal cancer who underwent laparoscopic-assisted TaTME in the First Hospital of Jilin University from May 2017 to December 2018 were collected.There were 39 males and 16 females,aged (60-± 11) years,with a range from 24 to 80 years.Among the 55 patients,21 were in TNM stage Ⅰ,14 were in TNM stage Ⅱ,and 20 were in TNM stage Ⅲ;24 were in pathological stage T1-2 and 31 were in pathological stage T3.Observation indicators:(1) surgical and postoperative conditions;(2) follow-up;(3) analysis of influencing factors for postoperative defecation function.Follow-up was performed using questionnaires by telephone interview to detect the complications at 3 and 6 months after surgery up to June 2019.The measurement data with normal distribution were expressed as Mean± SD,and comparison between groups was done using the t test.Count data were expressed as absolute numbers or percentages,and comparison between groups was analyzed using the chi-square test or Fisher exact probability.Univariate and multivariate analyses were performed using logistic regression models.Results (1) Surgical and postoperative conditions:55 patients successfully underwent laparoscopic-assisted TaTME without conversion to open surgery.The operation time,volume of intraoperative blood loss,diameter of postoperative pathological specimen,time to urinary catheter removal,distance between the anastomostic stoma and anal verge,and tumor diameter were (246±62) minutes,(69±27) mL,(3.5±0.7) cm,(2.1±0.9) days,(2.4±0.5) cm,and (3.9-± 1.6)cm,respectively.(2) Follow-up:55 patients were followed up at 3 months and 6 months after surgery,and the low anterior resection syndrome questionnaires were completed.Among the 55 patients,35 had low anterior resection syndrome at 3 months after surgery,and 24 had low anterior resection syndrome at 6 months after surgery,showing a significant difference (x2 =4.42,P＜0.05).There was no new onset low anterior resection syndrome in 55 patients after 3 months.(3) Analysis of influencing factors for defecation function:univariate analysis showed that the distance between the anastomotic stoma and anal verge and tumor diameter were influencing factors affecting defecation function of patients at 3 months after surgery (x2 =19.075,8.185,P＜ 0.05).The distance between the anastomotic stoma and anal verge was a influencing factor affecting the defecation function of patients at 6 months after surgery (x2=9.183,P＜0.05).Multivariate analysis showed that the distance between the anastomotic stoma and anal verge ＜ 2 cm,and tumor diameter ＞5 cm were independent risk factors affecting the defecation function of patients at 3 months after surgery (odds ratio =1.135,6.057,95％ confidence interval:1.089-1.323,1.206-30.435,P＜0.05).The distance between the anastomotic stoma and anal verge ＜ 2 cm was an independent risk factor affecting the defecation function of patients at 6 months after surgery (odds ratio =2.724,95％ confidence interval:1.982-3.066,P＜0.05).Conclusions The incidence of low anterior resection syndrome after laparoscopic-assisted TaTME for low rectal cancer is high.Distance between the anastomotic stoma and anal verge and tumor diameter are independent risk factors for the postoperative defecation founction.

Management and re-thinking of low anterior resection syndrome based on present anal preservation strategy / 中华胃肠外科杂志

Low anterior resection syndrome (LARS) is defined as a syndrome characterized by various abnormal defecation symptoms, including increased defecation times, urgency, frequent defecation, and fecal incontinence. LARS commonly develops after sphincter-preserving operation or reduction of protective ileostomy. The symptoms of LARS will alleviate gradually, and some patients may return to normal or basically normal. However, 60%-80% of the patients remains to suffer from LARS. Their daily life and psychosocial functionare seriously impaired. At present, the etiology of LARS is not well understood, but many factors are associated with LARS, such as tumor location, radiotherapy and surgical techniques and so on.

Analysis on prognosis and influencing factors of postoperative low anterior resection syndrome for rectal cancer patients undergoing laparoscopic anus-preserving radical resection / 中华胃肠外科杂志

Objective@#To investigate the prognosis and influencing factors of postoperative low anterior resection syndrome (LARS) for rectal cancer patients undergoing laparoscopic sphincter-preserving radical resection.@*Methods@#A retrospective case-control study was used in this study. Clinical data of 268 rectal cancer patients undergoing laparoscopic sphincter-preserving radical resection at Department of Gastrointestinal Surgery of The First Affiliated Hospital of Bengbu Medical College from January 2016 to January 2018 were retrospectively collected. Inclusion criteria: (1) operation procedure was total mesorectal excision (TME) and sphincter-preserving radical resection; (2) rectal cancer was confirmed by postoperative pathology; (3) age of patient was ≥ 18 years old. Exclusion criteria: (1) patient who had history of pelvic surgery and pelvic fractures, which would affect the anorectal function; (2) patient who had history of preoperative chronic constipation and irritable bowel syndrome, which would affect defecation; (3) patient who developed postoperative complications, such as anastomotic leakage, which would affect defecation function; (4) patient who received long-term use of drugs, which would affect the function of gastrointestinal tract or anus; (5) patient suffered from mental illness, who was unable to communicate properly; (6) patient who was lack of clinical data or had incomplete clinical data. Patients were followed up at 3, 6 and 12 months postoperatively, and LARS was diagnosed and graded according to the LARS score scale. The LARS score ranged from 0 to 42 points, and 0 to 20 was difined as no LARS, 21 to 29 was mild LARS, and 30 to 42 was severe LARS. LARS score >20 points at any time point was defined as postoperative LARS. Severe LARS transferring into mild LARS and mild LARS transferring into no LARS was defined as symptom improvement. Incidence and outcomes of LARS were evaluated. The factors associated with LARS outcomes were analyzed using χ2 test and logistic regression model.@*Results@#A total of 268 patients were enrolled. The incidence of LARS was 42.9% (115/268), 32.5% (87/268) and 20.1% (54/268) at 3, 6, and 12 months postoperatively respectively, and no new case of LARS was found after 3 months postoperatively. The incidence of mild LARS was 25.7% (69/268), 17.2% (46/268) and 8.6% (23/268) at 3, 6, and 12 months postoperatively respectively, and mild LARS incidence at 6 months was significantly lower than that at 3 months (χ2=5.857, P=0.016), and was significantly higher than that at 12 months (χ2=8.799, P=0.003). The incidence of severe LARS was 17.2% (46/268), 15.3% (41/268) and 11.6% (31/268) at 3, 6, and 12 months postoperatively respectively, without significant difference among 3 time points (all P>0.05). The improvement rate within one year after surgery in patients with mild LARS diagnosed at 3 months was significantly higher than that in patients with severe LARS (88.4% vs. 32.6%, χ2=38.340, P<0.001). Univariate analysis showed that female, distance from anastomosis to anal verge < 5 cm and tumor diameter ≥ 5 cm were associated with unsatisfied LARS outcomes (all P<0.05). Logistic regression analysis showed that distance from anastomosis to anal verge <5 cm was an independent risk factor for LARS outcome (OR=3.589, 95% CI: 1.163 to 2.198, P<0.001).@*Conclusions@#The incidence of LARS after laparoscopic sphincter-preserving radical resection decreases with time. The improvement rate within postoperative 1-year of severe LARS is lower than that of mild LARS. Low anastomotic position may lead to impaired improvement of LARS.

Adaptación transcultural del cuestionario acerca de la función intestinal (LARS Score) para su aplicación en pacientes operados de cáncer de recto medio y bajo / Cross-cultural adaptation of a bowel function questionnaire (LARS Score) for application in patients operated on for medium and low rectal cancer

Introducción: El tratamiento en el cáncer de recto ha progresado en la última década. Hoy es factible ofrecer una cirugía con preservación de esfínteres, realizando anastomosis colorrectales bajas o anastomosis coloanales. Esto ha determinado que muchos pacientes desarrollen disfunción intestinal que puede llegar a ser severa, agrupando una serie de alteraciones que se conocen como síndrome de resección anterior baja. Objetivo: Efectuar una adaptación cultural de la versión 1.0 en español neutro del cuestionario acerca de la función intestinal o Low Anterior Resection Syndrome Score (LARS Score), efectuando traducción, comparación de traducciones, traducción inversa y prueba piloto. Resultados: Los resultados obtenidos de la prueba piloto revelan que la población encuestada logró comprender el instrumento, por lo que no se realizaron modificaciones posteriores. Conclusión: Se cuenta con una versión adaptada del cuestionario LARS para ser usada en Chile, la cual puede someterse a procesos de validación y establecer las características psicométricas para ser usada en pacientes con cáncer de recto operados.

Introduction: The treatment of rectal cancer has progressed in the past decade. Nowadays, it's feasible to provide sphincter sparing surgery with low colorectal anastomosis or coloanal anastomosis. This has determined that many patients develop intestinal dysfunctions that can become severe, grouping a number of disorders known as low anterior resection syndrome. Objective: To perform a cultural adaptation of the version 1.0 questionnaire about bowel function or Low Resection Syndrome Score (LARS Score) in neutral Spanish, making a translation, comparing translations, back translation and pilot test. Results: The results of the pilot test showed that the population surveyed understood the instrument, so that no further modifications were made. Conclusion: We now have an adapted version of the LARS questionnaire for use in Chile, which can undergo validation processes to establish the psychometric characteristics for use in patients with rectal cancer surgery.

Colorectal Perforation After Anorectal Manometry for Low Anterior Resection Syndrome

We experienced 3 cases of manometry-induced colon perforation. A 75-year-old man (case 1) underwent anorectal manometry (ARM) 3 years after radiotherapy for prostate cancer and a laparoscopic intersphincteric resection for rectal cancer. A 70-year-old man (case 2) underwent ARM 3 months after conventional neoadjuvant chemoradiotherapy and a laparoscopic low anterior resection for rectal cancer. A 78-year-old man (case 3) underwent ARM 2 months after a laparoscopic intersphincteric resection for rectal cancer. In all cases, a colon perforation with fecal peritonitis occurred. All were treated successfully using prompt and active operations and were discharged without any complications. ARM with a balloon, as a measure of rectal compliance, should be performed 2 months or longer after surgery. If a perforation occurs, prompt and active surgical intervention is necessary due to the high possibility of extensive fecal peritonitis.

Alteraciones de la función intestinal y de la continencia fecal posteriores a cirugía preservadora de esfínteres por cáncer de recto / Alterations of intestinal function and fecal continence after sphincter-preserving surgery due to rectal cancer

Objetivo: Cuantificar el grado de severidad del síndrome de resección anterior baja (SRAB) en pacientes postoperados de cirugía preservadora de esfínteres (CPE). Sede: Unidad de Coloproctología del Hospital General de México ''Dr. Eduardo Liceaga''. Diseño: Estudio descriptivo de cohorte transversal. Análisis estadístico: Porcentajes como medida de resumen para variables cualitativas. Pacientes y métodos: Se incluyeron 30 pacientes tratados con cirugía preservadora de esfínteres, de enero 2007 a diciembre del 2011. A dichos pacientes se les evaluó por medio de la escala de síndrome de resección anterior baja del Hospital Universitario de Aarhus, en Dinamarca, de cinco parámetros. Se evaluó la prevalencia del síndrome de resección anterior baja, intensidad con base en el tiempo y la distancia del tumor al margen anal. Resultados: El 60% de los pacientes se encontró con síndrome de resección anterior baja, con un seguimiento promedio de 20 meses. La incontinencia a líquidos estuvo presente en el 48%, fraccionamiento de defecación 21%, urgencia defecatoria 17%; los otros dos parámetros evaluados prácticamente no se presentaron. El grado más severo de síndrome de resección anterior baja se observó en los primeros 8 meses posteriores a la cirugía y sólo un paciente, después de 24 meses de operado, continuó con sintomatología severa. Los pacientes con tumores entre 7 y 10 cm del margen del ano no desarrollaron las alteraciones evaluadas o éstas fueron leves. Todos los pacientes con un tumor menor de 7 cm desarrollaron alteraciones severas. Conclusión: Las alteraciones más frecuentemente encontradas fueron la incontinencia fecal a líquidos, fraccionamiento de la defecación y urgencia defecatoria. Las alteraciones valoradas mediante la escala de síndrome de resección anterior baja fueron severas en los primeros meses posteriores a la cirugía y cuando el tumor se encontraba más cerca del margen anal.

Objective: To assess the degree of severity of the low anterior resection syndrome (LARS) in patients after sphincter preserving surgery (SPS). Setting: Coloproctology unit of the General Hospital of Mexico ''Dr. Eduardo Liceaga'' (Third level health care hospital). Design: Cross-sectional cohort descriptive study. Statistical analysis: Percentages as summary measure for qualitative variables. Patients and methods: The study included 20 patients subjected to sphincter preserving surgery, from January 2007 to December 2011. These patients were evaluated according to the five-parameter LARS scale of the Aarhus University Hospital, in Denmark. We assessed prevalence of low anterior resection syndrome, intensity based on time and distance of the tumor from the anal margin. Results: Of the patients, 60% coursed with the low anterior resection syndrome with an average follow-up of 20 months. Incontinence to liquids was present in 48%, fragmented defecation in 21%, urgency to defecate in 17%; the other two assessed parameters were practically inexistent. The most severe degree of low anterior resection syndrome was seen in the first 8 months after surgery and only one patient, after 24 months of the surgery, continued with severe symptoms. Patients with tumors between 7 and 10 cm from the anal margin did not develop the assessed alterations or they were very mild. All patients with a tumor at less than 7 cm developed severe alterations. Conclusion: The most frequently found alterations were fecal incontinence to liquids, fragmented defecation, and urgency to defecate. The alterations assessed by the LARS scale were severe during the first months after surgery and when the tumor was closer to the anal margin.