¿Día o noche? El momento ideal para realizar la colecistectomía / Day or night? The right time to perform cholecystectomy

Introducción. La frecuencia de complicaciones postquirúrgicas de la colecistectomía realizada en la noche es un tema de controversia, siendo que se ha reportado una frecuencia mayor durante el horario nocturno. El objetivo de este estudio fue analizar la presentación de colecistectomía difícil dependiendo de la hora en que se realizó la cirugía, además de otras complicaciones, estancia intrahospitalaria postquirúrgica, reingreso a 30 días y reintervención. Métodos. Se realizó un estudio retrospectivo, observacional, analítico y transversal, comparando la presentación de colecistectomía difícil y su frecuencia en horario diurno (8:00 am a 7:59 pm) y nocturno (8:00 pm a 7:59 am), además de seroma, absceso, hematoma, fuga biliar, biloma, estancia intrahospitalaria postquirúrgica, reingreso a 30 días y reintervención. Resultados. Se incluyeron en el estudio 228 pacientes, 117 operados durante el día (52 %) y 111 durante la noche (48 %). La colecistectomía difícil se presentó 26 % vs 34 % de los casos intervenidos en el día y la noche, respectivamente. La complicación más frecuente fue seroma (14 %). La estancia hospitalaria media fue de 2,7 días en cirugías diurnas y de 2,5 en cirugías nocturnas; hubo 3 % de reintervenciones y 6 %, respectivamente. También hubo 2 % de reingresos a los 30 días entre los pacientes operados en el día y 3 % entre los operados en la noche. Conclusiones. La frecuencia de colecistectomía difícil y las complicaciones, la estancia intrahospitalaria postquirúrgica, el reingreso a 30 días y la necesidad de reintervención, no tuvieron diferencias significativas respecto al horario de la cirugía.

Introduction. The frequency of post-surgical complications of cholecystectomy performed overnight is a matter of controversy, and a higher rate has been reported during the night shift. The objective of this study was to analyze the presentation of difficult cholecystectomy depending on the time the surgery was performed, in addition to other complications, postoperative hospital stay, 30-day readmission, and reintervention. Methods. A retrospective, observational, analytical and cross-sectional study was carried out, comparing the presentation of difficult cholecystectomy and its frequency during daytime (8:00 am to 7:59 pm) and at night (8:00 pm to 7:59 am), in addition of seroma, abscess, bile leak, biloma, hematoma, post-surgical hospital stay, 30-day readmission, and reintervention.Results. A total of 228 patients were included in the study, 117 patients operated during the day (52%), and 111 at night (48%). Difficult cholecystectomy occurred in 26% vs. 34% of the cases operated on during the day and at night, respectively. The most frequent complication was seroma (14%). The mean hospital stay was 2.7 days in day surgeries and 2.5 in night surgeries; there were also 2% readmission at 30 days among patients operated during the day and 3% among those operated on at night. Conclusions. The frequency of difficult cholecystectomy and complications, postoperative hospital stay, 30-day readmission, and the need of reintervention, did not have significant differences with respect to the time of surgery.

Test de sangre oculta en deposiciones para programas de cribado de cáncer colorrectal: actualización / Fecal occult blood test for colorectal cancer screening

Screening programs for colorectal cancer (CRC) are standard in most developed countries because they reduce mortality and are cost-effective. Within them, colonoscopy allows to directly visualize the colon and remove neoplastic lesions. However, it is an expensive exam with low adherence in asymptomatic individuals. The fecal occult blood test (FOBT) is a low-cost and risk-free method for the user, which results in a high rate of adherence, explaining its use in most screening programs. This article analyzes the effectiveness of different fecal occult blood tests in screening programs. The main conclusions are that the sensitivity of the guaiac-based chemical test for the detection of colorectal cancer is lower than that observed with qualitative and quantitative immunological tests. Automated quantitative methods allow objective readings independent of the operator and the reaction reading time, necessary for the analysis of large numbers of samples. The participation rate with immunological FOBTs is higher than with chemical ones, which is why they are preferred by the different countries that have screening programs. The use of quantitative tests allows stratification of symptomatic and asymptomatic patients at higher risk, in the screening programs.

Cáncer sincrónico detectado con PET/ CT-Tomografía Computada contrastada (PET/CTc) en 210 pacientes con cáncer colorrectal recientemente diagnosticado / Synchronous tumors detected with contrast-enhanced F18-FDG positron emission tomography/computed tomography (PET/CTc) in colorectal cancer

Background: Colorectal cancer (CRC) is the third most prevalent cancer in the world and is the second cause of cancer death. Positron emission tomography/computed tomography (PET/CT) using 18F-FDG is used for its staging and follow up. Aim: To assess the occurrence of synchronous colonic and extracolonic tumors detected with contrast-enhanced F18-FDG PET/CT (PET/CTc) in patients with a recently diagnosed CRC. Material and Methods: PET/CTc of 210patients aged 16-91, years (63% men) with a recently diagnosed CRC were reviewed. PET/CTc with incidental findings, not expected to be due to CRC, were followed (laboratory, imaging and pathology) searching for synchronous tumors. Results: Ten patients (4,7%) had a second synchronous CRC. Only 70% of synchronous CRC were accessible to colonoscopy, due mainly to incomplete procedures for stenotic tumors. Extracolonic synchronous neoplasms were detected in 12 patients (5,7%), namely lung cancer in three, renal cell carcinoma in two, non-Hodgkin lymphoma in two, pancreatic cancer in one, breast cancer in one, hepatocellular carcinoma in one, bladder cancer in one and thyroid cancer in one. Conclusions: Ten percent of patients with a recently diagnosed CRC had a synchronic neoplasm detected at staging using PET/CTc.

Programa multicéntrico de cribado de cáncer colorrectal en Chile / Results of a multicentric colorectal cancer screening program in Chile

Background: Colorectal Cancer Screening Programs (CRCSP) are widely accepted in developed countries. Unfortunately, financial restrictions, low adherence rate and variability on colonoscopy standardization hamper the implementation of CRCSP in developing countries. Aim: To analyze a multicentric pilot model of CRCSP in Chile. Material and Methods: A prospective model of CRCSP was carried out in three cities, from 2012 to 2015. The model was based on CRC risk assessment and patient education. Health care personnel were trained about logistics and protocols. The endoscopy team was trained about colonoscopy standards. A registered nurse was the coordinator in each center. We screened asymptomatic population aged between 50 and 75 years. Immunological fecal occult blood test (FIT) was offered to all participants. Subjects with positive FIT underwent colonoscopy. Results: A total of 12,668 individuals were enrolled, with a FIT compliance rate of 93.9% and 2,358 colonoscopies were performed. Two hundred and fifty high-risk adenomas and 110 cancer cases were diagnosed. One patient died before treatment due to cardiovascular disease, 74 patients (67%) underwent endoscopic resection and 35 had surgical treatment. Ninety one percent of patients had an early stage CRC (0-I-II). Among colonoscopy indicators, 80% of cases had an adequate bowel preparation (Boston > 6), cecal intubation rate was 97.7%, adenoma detection rate was 36.5%, and in 94.5% of colonoscopies, withdrawal time was adequate (> 8 min). Conclusions: This CRCS pilot model was associated to a high rate of FIT return and colonoscopy quality standards. Most CRCs detected with the program were treated by endoscopic resection.

Impacto de las filtraciones anastomóticas en cirugía colorrectal / Impact of anastomotic leak in colorectal surgery

Introducción: La filtración de anastomosis es una de las complicaciones de mayor impacto en cirugía colorrectal. Objetivo: Analizar la frecuencia e impacto de las filtraciones anastomóticas en cirugía laparoscópica colorrectal. Material y método: Estudio longitudinal de base de datos prospectiva de pacientes operados por cirugía colorrectal entre julio de 2007 y agosto de 2014. Resultados: De un total de 654 pacientes operados, 52,3% correspondían a hombres con una edad promedio de 57 años (42-72). La indicación más frecuente fue cáncer colorrectal con 244 pacientes, 159 (24,3%) operados por cáncer de colon y 85 (12,9%) por cáncer de recto, seguido por la enfermedad diverticular con 239 pacientes (36,5%) y 171 pacientes (26,1%) con otros diagnósticos. En 44 pacientes (6,7%) se objetivó filtración anastomótica, con una mediana de 4 días desde el postoperatorio para su diagnóstico. Como factores asociados a filtración se identificó al género masculino, riesgo anestesiológico según ASA, necesidad de conversión a laparotomía y la anastomosis ileoanal. En relación con el tratamiento, 15 pacientes (33,7%) fueron tratados de forma médica exitosa y 29 fue necesario reintervenirlos, de los cuales 23 (79,3%) requirieron una ostomía de protección. No hubo mortalidad asociada a la cirugía, y el promedio de hospitalización en los pacientes con filtración fue de 12 vs. 5 días para los pacientes sin filtración de la anastomosis. Conclusión: Este trabajo permite identificar a grupos de pacientes con mayor riesgo de filtraciones anastomóticas, quienes duplican su estadía hospitalaria y en un alto porcentaje deben ser reintervenidos. La sospecha y diagnostico precoz reducen la morbimortalidad.

Introduction: Anastomotic leak is the most important complication on colorectal surgery. Objective: Analyze the frequency and impact of anastomotic leaks in laparoscopic colorectal surgery. Material and methods: Longitudinal study of prospective database of patients undergoing colorectal surgery between July 2007 and August 2014. Results: 654 patients operated, 52.3% were men with an average age of 57 years (42-72). The most frequent indication was colorectal cancer in 244 patients, 159 (24.3%) operated for colon cancer and 85 (12.9%) for rectal cancer followed by diverticular disease in 239 patients (36.5%) and 171 patients (26.1%) with other diagnoses. In 44 patients (6.7%) anastomotic leakage was observed with a median of 4 days post surgery for diagnosis. As factors associated with filtration, we identified male gender, anesthesic risk according to ASA, need for conversion to laparotomy and ileoanal anastomosis. With regard to treatment, 15 (33.7%) were successfully treated with medical therapy alone and 29 required re-intervention, of which 23 (79.3%) required an ostomy protection. There was no mortality associated with surgery and average LOS was 12 vs. 5 days in patients with filtration compared with patients without anastomotic leakeage. Conclusion: This serie helps to identify patients groups with increased risk of anastomotic leakage who double their hospital LOS and in a higher percentage should need re-intervention. Suspicion and early diagnosis reduces morbidity and mortality.

Se justifica el seguimiento después de una colectomía en pacientes con poliposis adenomatosa familiar / The follow up after colectomy in patients with familial adenomatous polyposis is justified

phenotypic expression is the presence of múltiple colorectal adenomatous polyps (more than 100), with high probability developing colorrectal cancer (CRC) before the fifth decade of life. Prophylactic surgery (total colectomy or restorative proctocolectomy) reduces the risk of developing CRC. However, the risk of developing tumors in other organs remains present. Objetive: Analyze the frequency and type of tumors associated with classic familial adenomatous polyposis syndrome (FAPc) patients undergoing prophylactic colectomy. Material and Methods: Cohort study. From the registry of hereditary colorrectal cancer (CRC) at our institution, we identified patients with FAPc who underwent total colectomy with ileorrectal anastomosis (TC-IRA) or restorative proctocolectomy (RTPC), from 1999 to 2014. In the follow-up we analyzed related tumors and mortality. Results: 27 patients, of whom 18 (66.7%) underwent TC-IRA and 9 (33.3%) underwent RTPC. At the time of surgery, 4 patients had CRC (15%) and 5 had extracolonic tumors (osteomas). In a mean follow-up of 49, 4 months (i: 2 y 178) the following lesions were diagnosed: digestive tract adenomas in 17 (63%) patients, of these 2 required a proctectomy and 3 resection of duodenal adenomas. Eight patients developed desmoid tumors (30%), and 3 of them underwent surgery. One patient had an extradigestive tumor (thyroid cancer) and only 8/27 (29.6%) did not develop other tumors. One patient died due to progression of his CCR. Discussion: In this series it is confirmed that most patients will develop neoplasms FAPc after colectomy. conclusion: The removal of the colon and/or rectum is able to prevent the development of CRC. However, two thirds of the patients develop other tumors in which systematic surveillance allowed early detection and treatment.

Objetivo: Analizar la frecuencia y tipo de tumores asociados en pacientes con poliposis adenomatosa familiar clásica (PAFc) sometidos a una colectomía profiláctica. Materiales y Métodos: Estudio de cohorte. Desde el registro de cáncer colorrectal (CCR) hereditario, se identificaron las familias con PAFc, y de estas a los pacientes que se les practicó una colectomía total con anastomosis íleorrectal (CT-AIR) o proctocolec-tomía restauradora (PCTR), desde 1999 al 2014. En el seguimiento se analizaron los tumores asociados y su mortalidad. Resultados: Se identificaron 27 pacientes, de los cuales 18 (66,7%) fueron sometidos a CT-AIR y 9 (33,3%) a PCTR. Al momento de la cirugía, 4 pacientes presentaban CCR (15%) y 5 tenían tumores extracolónicos (osteomas). En un seguimiento promedio de 49,4 meses (i: 2 y 178) se diagnosticaron: adenomas del tracto digestivo en 17 (63%) pacientes, de éstos 2 requirieron una proctectomía y 3 resecciones de adenomas duodenales. Ocho pacientes desarrollaron tumores desmoides (30%), y 3 de ellos fueron sometidos a una cirugía. Un paciente presentó un tumor extradigestivo (cáncer de tiroides) y sólo 8/27 (29,6%) pacientes no desarrollaron otros tumores. Un paciente falleció por progresión de su CCR. Discusión: En esta serie se confirma que la mayoría de los pacientes con PAFc seguirán desarrollando neoplasias después de su colectomía. conclusiones: La extirpación del colon y/o recto permitió evitar el desarrollo de CCR. Sin embargo, dos tercios de los pacientes presentaron otros tumores en quienes su seguimiento permitió una detección y tratamiento temprano.

Trauma cardiaco cerrado / Blunt cardiac trauma

El trauma cardiaco constituye una de las primeras causas de mortalidad en la población general. Requiere alto índice de sospecha en trauma cerrado severo, mecanismo de desaceleración y en presencia de signos indirectos como: equimosis, huella del volante o del cinturón en el tórax anterior. Las lesiones incluyen: conmoción cardiaca, ruptura cardiaca, lesión cardiaca indirecta como la trombosis coronaria aguda, lesión aórtica, lesión del pericardio y herniación cardiaca. Entre las manifestaciones clínicas están: la angina refractaria a nitratos, el dolor pleurítico, la hipotensión arterial, la taquicardia, la ingurgitación yugular que aumenta con la inspiración, el galope por tercer ruido, el frote pericárdico, los soplos de reciente aparición, los estertores crepitantes por edema pulmonar. El electrocardiograma es el primer eslabón en el algoritmo diagnóstico con hallazgos como: la taquicardia sinusal, los complejos ventriculares prematuros, la fibrilación auricular, el bloqueo de rama derecha y los bloqueos auriculoventriculares. La radiografía de tórax ayuda a descartar lesiones adicionales óseas y pulmonares. La troponina I tiene un valor predictivo negativo del 93% para el trauma cardiaco, otras enzimas como la creatina quinasa total y la creatina quinasa fracción MB son menos específicas. El ecocardiograma está indicado en caso de hipotensión persistente, electrocardiograma con alteraciones o falla cardiaca aguda. El tratamiento incluye la estabilización inicial y un manejo específico de las lesiones. Entre las complicaciones se incluyen: el taponamiento cardiaco, la contusión miocárdica, el síndrome coronario agudo, las arritmias cardíacas y la lesión aórtica. El pronóstico se determina en mayor medida por los signos vitales al ingreso y la presencia de paro cardiaco durante el abordaje inicial.

Cardiac trauma is one of the primary causes of death amongst general population. It requires a high degree of suspicion of severe blunt trauma, deceleration mechanism and presence of indirect signs, such as ecchymosis and steering wheel or seatbelt marks in the anterior chest wall. Injuries include: cardiac concussion, heart rupture, indirect cardiac injury, such as acute coronary thrombosis, aortic injury, pericardial injury and cardiac herniation. The clinical signs and symptoms include: angina refractory to nitrates, pleuritic pain, hypotension, tachycardia, jugular venous distention that increases on inspiration, S3 gallop, pericardial rub, new murmur or crepitant rales due to pulmonary edema. The electrocardiogram is the first link in the diagnostic algorithm leading to findings such as sinus tachycardia, premature ventricular complexes, atrial fibrillation, right bundle branch block and atrioventricular block. Chest X-rays help to rule out other pulmonary or bone injuries. Troponin I has a negative predictive value of 93% for cardiac trauma; other less specific cardiac enzymes are creatine kinase and creatine kinase-MB. Echocardiogram is indicated in presence of persistent hypotension, abnormal ECG results or acute heart failure. The treatment includes initial stabilization and specific management of the injuries. Some complications may include: cardiac tamponade, myocardial contusion, acute coronary syndrome, cardiac arrhythmias and aortic injury. The prognosis of the patient depends on the vital signs at the time of arrival at the emergency department and the presence of cardiac arrest during the initial approach.

Análisis molecular del cáncer de colon esporádico / Molecular analysis of sporadic colon cancer

Background: In Chile, colorectal cancer (CRC) is often diagnosed in late stages. Thus, surgical treatment must be complemented with chemotherapy. KRAS mutations and microsatellite instability have been detected in these tumors. However, the response to treatment in patients without KRAS mutations varies and requires a better understanding. Aim: To determine the frequency and distribution of somatic point mutations in KRAS, BRAF and PIK3CA genes and microsatellite instability status (MSI) in patients with colon cancer (CC). Material and Methods: A prospective observational study of patients undergoing surgery for colon cancer. Tumor-derived DNA was analyzed by polymerase chain reaction (PCR) for the most frequent mutations of KRAS, BRAF and PIK3CA. PCR was also used to analyze MSI. Results: Fifty-eight patients with sporadic CC were analyzed, 16 showed KRAS mutations (G12R, G12D, G12V, G13D) and out of the 42 patients that did not show any mutation, 10 had mutations in BRAF (V600E) and PIK3CA (E542K, E545D, E545K, Q546E, H1047R). BRAF mutations alone or in combination with PIK3CA mutations were observed in 27% of high MSI tumors and in 2% of tumors without instability (p < 0.049). A higher percentage of high MSI tumors were located in the right colon (p < 0.001), and showed BRAF mutation (p < 0.020). Conclusions: The highest percentage of high MSI and BRAF mutations was observed in the right colon. Therefore, this study suggests the presence of different molecular features between right and left colon tumors that should be considered when defining the therapeutic management.

Prevalencia y características de mutaciones somáticas del gen KRAS en pacientes chilenos con cáncer colorrectal / KRAS gene somatic mutations in Chilean patients with colorectal cancer

Background: The molecular testing of KRAS mutation status in metastatic colorectal cancer patients is mandatory to identify patients eligible for anti-epidermal growth factor receptor monoclonal antibody therapy. Aim: To report the frequency of KRAS gene mutations in Chilean patients with colorectal cancer (CRC). Material and Methods: A cohort of 262 Chilean patients with CRC aged 26 to 90 years (53% males), was studied. KRAS mutation status was analyzed by real-time polymerase chain reaction and correlated with clinicopathological data. Results: Ninety-eight patients (37%) were positive for KRAS mutations. G12D was the most common mutation with a frequency of 36.7%, followed by G12V (25.5%), G13D (17.3%), G12A (7.1%), G12C (6.1%), G12S (5.1%) and G12R (2%). The frequency of the mutation in left, right colon and rectal tumors was 37.8, 32.6 and 44.9%, respectively. Among tumors with mutations, 86.7% were well or moderately differentiated tumors and the rest were poorly differentiated. No significant associations between KRAS gene mutations and other clinicopathological features of the tumor were observed. Conclusions: The frequencies of KRAS mutations reported in this study are similar to frequencies reported for European and North-American populations, lower than in a Spanish study and higher than in a Peruvian study.

Estudio EPRAS: estudio poblacional del riesgo cardiovascular de una población colombiana / EPRAS Study: population-based study of cardiovascular risk in a Colombian population

Objetivos: Describir el comportamiento de los factores de riesgo relacionados con la hipertensión arterial, el consumo declarado de medicamentos y el perfil metabólico en una población de pacientes valorados en el Servicio de Medicina Interna del Hospital Departamental Felipe Suárez de Salamina, Caldas, durante octubre a diciembre de 2012. Materiales y métodos: Se valoraron 400 pacientes hipertensos del servicio de Medicina Interna del Hospital Departamental Felipe Suárez, durante octubre a diciembre de 2012. Se aplicaron formatos de registro y se procesaron en forma descriptiva. Resultados: Se encontró una prevalencia de sedentarismo del 43,7% y de tabaquismo del 9,3%. En un 84,3% de los hipertensos evaluados se encontraron cifras de presión arterial controladas. El 73,3% tenía pobre control de las cifras de colesterol LDL. Los diuréticos fueron el grupo de medicamentos antihipertensivos de mayor consumo (87,2%). Conclusiones: La prevención y el control de los factores de riesgo cardiovascular deben convertirse en una prioridad, en una política pública saludable del sistema de salud, que impacte a la totalidad de la población, con el fin de disminuir la prevalencia ascendente de los denominados grandes síndromes del adulto, responsables de las mayores tasas relacionadas con morbimortalidad en la población general, a través de la promoción de estilos de vida saludables, realización de actividad física regular y detección temprana de factores de riesgo.

Objectives: To describe the behavior of risk factors associated with hypertension, reported consumption of drugs and metabolic profile in a population of patients evaluated in the internal medicine department of the Hospital Departamental Felipe Suárez of Salamina (in Caldas, Colombia) during the period between October and December 2012. Materials and methods: We evaluated 400 patients with hypertension of the internal medicine department of the Hospital Departamental Felipe Suárez during the months of October, November and December 2012. Registration forms were applied and processed in descriptive form. Results: We found a prevalence of sedentarism of 43.7% and smoking of 9.3%. In 84.3% of hypertensive patients evaluated we found controlled blood pressure. 73.3% had poor control of LDL cholesterol levels. The diuretics were the group of anti hypertensive medication with the highest consumption (87.2%). Conclusions: primary prevention and control of cardiovascular risk factors should be turned into a priority, healthy public policy in the health system, which impacts the entire population, in order to decrease the rising prevalence of so-called large adult syndromes and those which are responsible for the higher rates associated with morbidity and mortality in the general population through promotion of healthy lifestyles, physical activity and early detection of risk factors.

Impacto de un programa de nivelación de ciencias básicas en estudiantes de primer año de la carrera de Medicina / Effects on academic performance of a leveling program in basic sciences in first year medical students

Background: A significant number of students in health careers do not have the knowledge to approve basic courses. Therefore, educational programs to level off knowledge have been developed. Aim: To associate the results of a leveling program with the academic performance in cell biology (CB) and biochemistry (BC) of first year medical students. Material and Methods: We applied a test to first year medical students at the beginning and end of the leveling program (control test). The results obtained at the end of the leveling program were correlated with the results obtained in CB and BC. Results: Fifty seven of89 (64%) first year medical students met the study entry criteria (54% female). Students who completed the leveling program had a significantly higher approval rate in CB (93% versus 75%, P = 0.024), and in BC (95% versus 69%, P = 0.001). After completing the leveling program, the risk of failing CB and BC, decreased by 72 and 84% respectively Conclusions: This study shows that medical students who participate in the leveling program decrease the chances of failing in CB and BC.

Resultados oncológicos a largo plazo de pacientes sometidos a resección laparoscópica por cáncer de recto / Long term oncological outcomes of patients undergoing laparoscopic resection for rectal cancer

Introducción: En la actualidad hay consenso en la seguridad oncológica en la cirugía laparoscópica para el tratamiento del cáncer de colon, sin embargo, en el cáncer de recto (CR) los resultados a largo plazo, continúan siendo objeto de estudio. El objetivo de este trabajo es analizar la sobrevida a largo plazo en pacientes operados por adenocarcinoma de recto por vía laparoscópica. Material y Métodos: Desde la base de datos prospectiva de cirugía colorrectal laparoscópica se seleccionaron los pacientes operados por CR en el periodo entre octubre 2000 y diciembre 2009. Se excluyó a los pacientes con cáncer colorrectal hereditario. Se analizaron los datos de seguimiento los cuales son obtenidos mediante registros clínicos y datos del registro civil. Se realizó un análisis de sobrevida con el método de Kaplan-Meier. Resultados: En el periodo mencionado, 60 pacientes fueron operados por CR, 2 (3,4%) pacientes fallecieron en el postoperatorio temprano y fueron excluidos en el análisis de sobrevida, por tanto, 58 pacientes fueron incluidos en el seguimiento. El 41% eran sexo femenino y la edad promedio fue de 60 ± 11,6 años. Los tumores se encontraban localizados en el recto superior, medio e inferior en un 28%, 28% y 44% respectivamente. Las cirugías realizadas fueron resección abdominoperineal, resección anterior ultrabaja interesfintérica, resección anterior ultrabaja y resección anterior baja en un 8%, 28%, 5% y 59% de los pacientes, respectivamente. El 50% de los pacientes recibieron neoadyuvancia. Tras la estadificación postoperatoria 4% fueron clasificados estadio 0, 38% estadio I, 17% estadio II, 28% estadio III y 13% estadio IV. El recuento de linfonodos de la pieza operatoria fue de 12,3 en promedio. A un seguimiento de 42,6 meses (r: 17 a 103 meses) la sobrevida global estimada a 5 años es de 85%. Según estadios la sobrevida estimada a 5 años fue de 100% para el estadio 0 y I, 88% para el estadio II, 74% para el estadio III... (TRUNCADO)

Background: Currently there is a consensus in oncological safety for laparoscopic surgery for colon cancer; however, in rectal cancer long term outcomes are still a subject of debate. The aim is to analyze long term survival in patients who underwent laparoscopic surgery for rectal cancer. Material and Methods: From the prospective database of laparoscopic colorectal surgery, we selected patients operated on between October 2000 and December 2009. Patients with hereditary colorectal cancer were excluded. Follow-up data was obtained by medical records and national vital records. Survival was analyzed using the Kaplan-Meier method. Results: In this period, 60 patients were operated on for rectal cancer. Two died in the early postoperative period and were excluded from the analysis; therefore, 58 patients were included in follow-up. Forty-one percent were female and mean age was 60±11.6 years old. Tumors were localized in the upper, mid and lower rectum in 28%, 28% and 44%, respectively. Surgeries performed were abdominoperineal resection, ultra-low intersphincteric resection, ultralow anterior resection and low anterior resection in 8%, 28%, 5% and 59% of patients, respectively. Fifty percent received neoadjuvant treatment. After postoperative staging 4% were classified as stage 0,17% as stage I, 28% as stage II, 28% as stage III, and 13% as stage IV. At a mean 42.6 month follow-up (r: 17-103 months) estimated overall 5-year survival was 85%. When analyzed according to stage, estimated overall 5-year survival was 100% for stages 0 and I, 88% for stage II, 74% for stage III, and 57% for stage IV. Conclusion: Long term survival in patients undergoing laparoscopic surgery for rectal cancer is satisfactory and is within the values reported by international centers.

Síndrome de Lynch: selección de pacientes para el estudio genético mediante análisis de inestabilidad microsatelital e inmunohistoquímica / Lynch syndrome: selection of families by microsatellite instability and immunohistochemistry

Background: Selection of patients with Lynch Syndrome (LS) for a genetic study involves the application of clinical criteria. To increase the rate of identification of mutations, the use of molecular studies as Microsatellite Instability (MSI) and Im-munohistochemistry (IHC) in the tumor has been proposed. Aim: To demonstrate the usefulness of MSI and IHC in the detection of mutations in patients with LS. Material and Methods: From our Familial Colorectal Cancer Registry, families suspected of LS were selected according to Amsterdam or Bethesda clinical criteria. Screening of germline mutations of MLH1, MSH2 and MSH6 genes was performed. In addition, analysis of MSI and IHC were performed in colorectal tumors. Results: A total of 35 families were studied (19 met Amsterdam and 16 met Bethesda criteria). Twenty one families harbored a germline alteration in MLH1, MSH2 or MSH6 (18 Amsterdam and 3 Bethesda). In these families, eighteen different alterations were found, 15 of which were mutations and 3 corresponded to variants of uncertain pathogenicity. On the other hand, 80% of the tumors showed positive microsatellite instability (27 MSI-high and 1 MSI-low), and immunohistochemical testing showed that 77% of tumors had the loss of a protein. Correlation between results of tumor molecular studies and the finding of germline nucleotide change showed that IHC and MSI predicted mutations in 81 and 100% of patients, respectively. Conclusions: MSI and IHC can efficiently select patients with a high probability of carrying a mutation in DNA repair genes.

Caracterización clínica y genética de las poliposis intestinales hereditarias / Clinics and genetic characteristics in hereditary colon polyposis

Se denomina pólipo intestinal a una lesión visible elevada o tumor que se proyecta desde la superficie epitelial al lumen visceral. En relación al número, presencia de antecedentes familiares, manifestaciones extraintestinales y estudios genéticos es que se constituyen diversas poliposis intestinales. Si bien, las poliposis intestinales se manifiestan en general en la edad adulta, existen manifestaciones que pueden hacer sospechar la presencia de un síndrome poliposico hereditario en la infancia. Además en una proporción considerable estas poliposis presentan manifestaciones extraintestinales, tanto benignas como tumores en otros órganos. Es por esto, que una alta tasa de sospecha, en particular frente a pacientes con antecedentes familiares, puede conducir a un diagnóstico y tratamiento oportuno, además de considerar a la familia como potenciales pacientes e ingresar al grupo familiar a un registro de tumores hereditarios. Diversas técnicas de biología molecular han permitido la identificación de las mutaciones que son heredadas en estas enfermedades, permitiendo realizar conductas preventivas al saber el riesgo de cada persona en una familia afectada. El objetivo de esta revisión, es caracterizar las distintas poliposis intestinales, en cuanto a sus manifestaciones clínicas, clasificaciones, estudio genético y enfrentamiento multidisciplinario.

Polyps are solid or tumoral elevated lesions that arise from the intestinal epithelium so that they become visible in the intestinal epithelium so that they become visible in the intestinal lumen. Information regarding familial history, number, extraintestinal manifestations and genetic studies of polyps, assemble different types of intestinal polyposis. Generally, clinical manifestations occur in adult patients, although in children there are several signs that should make the physician suspect a hereditary polyposis syndrome. In addition it is important to know extraintestinal manifestations which are mostly benign but tumors may be present in other organs too. Bearing in mind that high clínical suspicion of hereditary polyposis syndrome especially if familial history is present, provides early diagnosis and appropriate treatment for the patient and eventually for the family members that could be affected, entering that family in a registry of hereditary tumors. Molecular biology has created different techniques to identify the presence of hereditary mutations that are specific for intestinal polyposis. Acknowledgment of these mutations establishes risks groups allowing adequate prevention strategies. The objective of this revision is to characterize and different types of intestinal polyposis, according to clinical manifestations, classification, genetic study and multidisciplinary approach.

Programa de detección de neoplasias colorrectales en población mayor de 50 años / A screening program for colorectal cancer in Chilean subjects aged fifty years or more

Background: Mortality from colorectal cancer (CCR) in Chile has nearly doubled over the past 15 years. International studies have shown that CCR screening programs based on fecal occult blood test (FOBT) reduce CCR mortality. Aim: To analyze the results from a CCR screening model in people over 50 years. Material and Methods: Between 2007 and 2009, a prospective multicenter study was performed in seven major Chilean cities. FOBT using an immunological method, was measured in asymptomatic subjects aged 50 years or more, without risk factors. In patients with a positive FOBT, with symptoms or with family risk factors, a colonoscopy was indicated. Results: A total of 6348 subjects were assessed, FOBT was performed in 4938 of them, with a compliance of 77%. The result was positive in 9.6%. A total of 2359 colonoscopies were ordered, with an overall compliance of 50.1%. Of the 1184 colonoscopies performed, adenomas and high risk adenomas were found in 304 (26%) and 75 (6%) patients, respectively. Thirteen patients were diagnosed with stage I and IICCR. Three of these lesions were excised endoscopically and 10 surgically. The detection rate of polyps, high risk adenomas and cancer was 75, 12 and 2 per 1000 screened individuals, respectively. Conclusions: This program allowed the early detection of an important number of high risk colon lesions, and all patients with CCR were diagnosed at early stages.

Prevalencia de la incontinencia fecal en centros de salud y casas de reposo / Prevalence of fecal incontinence in health centers and nursing home residents

Background: Fecal and urinary incontinence (FI and UI) are psychologically and socially debilitating and embarrassing conditions. Aim: To determine the prevalence of FI and associated factors in patients assessed in health centers (HC) and nursing home (NH) residents. Material and Methods: Prospective, multicentric survey carried out in 3 HC and 16 NH of Santiago. Patients and residents of NH were interrogated about FI between March and July 2004. Results: The questionnaire was answered by 618 patients attending health centers aged 18 to 87 years (75 percent females) and 128 nursing home residents aged 40 to 103 years (80 percent females). The prevalence of liquid or solid FI in HC and NH was 2.7 and 45 percent, respectively. Among the latter, the incontinence for liquids and solids was 19 percent and 42 percent, respectively. The prevalence of UI was 30.1 and 62.7 percent in HC patients and NH residents, respectively. Among patients attending HC, multivariable analysis showed a relation between older age and urinary incontinence with liquid or solid FI Among NH residents, multivariate analysis showed a relation between urinary incontinence and motor disabilities with liquid or solid FI Conclusions: The prevalence of liquid or solid FI among patients assessed in health center is 2.7 percent. This figure increases in older people, those with UI and in NH residents.

Síndrome de Lynch: Caracterización genético clínica. Caso clínico / Hereditary non-polyposis colorectal cancer: Report of four siblings

Hereditary non-polyposis colorectal cancer (HNPCC) or Lynch Syndrome is an autosomic dominant syndrome involving 596-1096 of colorectal cancer patients. Mutations in MLH1 and MSH2 genes account for most cases. These two genes particípate in the DNA mismatch repair pathway. Therefore mutation carriers show microsatellite instability (MSI) in tumors. This syndrome is characterized by the early development of colorectal cancer (before 50 years) and an increased incidence of cancer in other organs. We report four siblings from a family diagnosed with HNPCC. All of them were subjected to colonic surgery for colorectal cancer Moreover, one patient developed an ampulloma after her colon surgery. The molecular-genetic analysis revealed three brothers with microsatellite instability in the tumor tissue, the absence of the MLH1 protein, and the presence of a germ Une mutation localized in introm 15 ofthe MLH1 gene.

Resultados de la cirugía laparoscópica en el tratamiento electivo de la enfermedad diverticular de colon / Results of laparoscopic surgery for the treatment of diverticular disease of the colon

The laparoscopic approach is an alternative for the elective treatment of diverticular colon disease (DCD). Aim: To analyze the results of patients electively operated for DCD using a laparoscopic technique. Material and Methods: Data of patients with DCD operated using laparoscopy at the Catholic University of Chile Clinical Hospital were prospectively recorded from January 1999 to August 2006. Indications for surgery were repetitive crises of acute diverticulitis, the persistence of the symptoms or anatomic deformity after the first crisis and complicated diverticulitis (Hinchey 1-2) that responded to the medical treatment. The laparoscopic technique used five ports and the surgical specimen was extracted through a suprapubic approach. Results: One hundred and six patients aged 32 to 82 years (49 percent females) were operated in the study period. Fifty five percent had a previous abdominal surgery. The mean operative time was 213 minutes (range: 135-360). Four patients were converted to open surgery (3.7 percent). One or more early post-operative complications were observed in five patients (4.7 percent). The mean time for passing gases and reinitiate liquid diet was 1.7 and 2.4 days respectively. The median post operative stay after surgery was 4 days. There was no operative mortality. Mean follow-up time was 27 months and only one patient (0.9 percent) had a new episode of acute diverticular disease, with a satisfactory response to medical treatment. No patient has developed bowel obstruction. Conclusions: The laparoscopic approach is a safe alternative in the elective surgical treatment of DCD.