Sergio Báez V

Mitochondrial DNA Mutation at the D310 (Displacement Loop) Mononucleotide Sequence in the Pathogenesis of Gallbladder Carcinoma

Purpose: Mutations in the mitochondrial DNA (mtDNA) have been observed frequently in human neoplasia, in both coding and noncoding regions. A mononucleotide repeat (poly-C) between 303 and 315 nucleotides (D310) within the regulatory displacement loop has been identified recently as a frequent hot spot of deletion/insertion mutations in tumors. We investigated the frequency and pattern of D310 abnormalities in the pathogenesis of gallbladder carcinoma (GBC). Experimental Design: DNA extracted from neoplastic and nonneoplastic archival gallbladder tissue including 123 tumors, 53 dysplastic areas, and 90 histologically normal epithelia adjacent to GBC, chronic cholecystitis, and 15 normal gallbladders were examined by PCR-based assay for D310 mutations, followed by sequencing in a subset of cases. Results: D310 mutation was a relatively frequent (47 of 123; 38%) abnormality in GBC. A very high frequency of mutations were detected in dysplastic (8 of 14; 57%) and normal-appearing gallbladder epithelia (10 of 22; 46%) accompanying GBC, showing a clonal relationship compared with the corresponding tumors. D310 mutations were also detected in dysplastic (8 of 39; 21%) and normal (17 of 68; 25%) epithelia obtained from chronic cholecystitis. A single case of 15 normal gallbladders showed a D310 abnormality. Overall, deletions (67 of 91; 74%) at D310 were more frequent than insertions. Conclusions: D310 mutation at the mtDNA displacement loop is a relatively frequent and early event in the sequential pathogenesis of GBC, being detected in normal-appearing epithelium from chronic cholecystitis. Our findings suggest that mtDNA mutations should be additionally investigated in GBC pathogenesis, and D310 mononucleotide abnormalities could be included in a panel of molecular biomarkers for GBC early detection strategy.

Apendicectomía en la embarazada: Experiencia en un hospital público chileno

7 weeks, were operated because of a presumptive acute appendicitis. Forty (87%)had a histopathologically proven appendicitis; ten (25%) cases had a perforated appendix and 30 (75%) hada non-perforated appendicitis. Five (10.9%) patients had a negative laparotomy and one had a necroticovarian tumor. Patients with perforated and non perforated appendices had a similar lapse from the onset ofsymptoms to operation (69

Gastrectomía totalmente laparoscópica por neoplasias gástricas: Experiencia en un centro público

Background: The laparoscopic approach for the treatment of gastric tumors has many advantages. Aim: To evaluate the results of a laparoscopic gastrectomy program developed in a public hospital. Patients and Methods: Retrospective review of epidemiological, perioperative and follow-up data of patients who were treated with a laparoscopic gastrectomy due to gastric tumors between 2006 and 2013. A totally laparoscopic technique was used for all cases. Complications were evaluated according to the Clavien-Dindo classification. Results: Fifty one patients, aged 65 (36-85) years, underwent a laparoscopic gastrectomy. In 22 patients a total gastrectomy was performed. Conversion rate to open surgery was 8%. Operative time was 330 (90-500) min and bleeding was 200 (20-500) ml. Median hospital stay was 7 (3-37) days. Postoperative morbidity was present in 17 (33%) patients, 3 (6%) patients had complications grade 3 or higher and one patient died (1.9%). Tumor pathology was adenocarcinoma in 39 patients. A complete resection was achieved in 97%. Twenty nine patients (74%) with gastric adenocarcinoma had early gastric cancer and 84% of patients were in stage one. Median lymph node count was 24. Median follow-up was 26 (1-91) months. There was no cancer related mortality among patients subjected to a curative resection. Overall survival for patients with adenocarcinoma was 92% at 3 years. Conclusions: This study supports the feasibility and safety of a laparoscopic gastrectomy program in a public hospital; with low morbidity, adequate lymph node dissection and long-term survival. This approach must be considered an option for selected patients with gastric cancer.BACKGROUND The laparoscopic approach for the treatment of gastric tumors has many advantages. AIM To evaluate the results of a laparoscopic gastrectomy program developed in a public hospital. PATIENTS AND METHODS Retrospective review of epidemiological, perioperative and follow-up data of patients who were treated with a laparoscopic gastrectomy due to gastric tumors between 2006 and 2013. A totally laparoscopic technique was used for all cases. Complications were evaluated according to the Clavien-Dindo classification. RESULTS Fifty one patients, aged 65 (36-85) years, underwent a laparoscopic gastrectomy. In 22 patients a total gastrectomy was performed. Conversion rate to open surgery was 8%. Operative time was 330 (90-500) min and bleeding was 200 (20-500) ml. Median hospital stay was 7 (3-37) days. Postoperative morbidity was present in 17 (33%) patients, 3 (6%) patients had complications grade 3 or higher and one patient died (1.9%). Tumor pathology was adenocarcinoma in 39 patients. A complete resection was achieved in 97%. Twenty nine patients (74%) with gastric adenocarcinoma had early gastric cancer and 84% of patients were in stage one. Median lymph node count was 24. Median follow-up was 26 (1-91) months. There was no cancer related mortality among patients subjected to a curative resection. Overall survival for patients with adenocarcinoma was 92% at 3 years. CONCLUSIONS This study supports the feasibility and safety of a laparoscopic gastrectomy program in a public hospital; with low morbidity, adequate lymph node dissection and long-term survival. This approach must be considered an option for selected patients with gastric cancer.

Resultados actuales de la pancreatoduodenectomía para el tratamiento de los tumores periampulares y análisis de factores pronósticos de sobrevida

Background: The diagnosis and treatment of periampullary tumors represents a challenge for current medicine. Aim: To review the results of pancreaticoduodenectomy (PDD) in the treatment of periampullary tumors and to identify risk factors that impact the long-term survival. Patients and Methods: We performed a retrospective study of patients who underwent a PDD for periampullary tumors between 1993 and 2009. We reviewed perioperative results and long term survival. We performed a multivariate analysis for long-term survival. Results: A PDD was performed in 181 patients aged 58 ± 12 years (98 females). Piloric preservation was done in 53% and a pancreatogastric anastomosis was used in 94% of cases. Morbidity was 62% and postoperative mortality was 5.5%. Pancreatic cancer was the most frequent pathological finding in 41%, followed by ampullary cancer in 28% and distal bile duct cancer in 16%. Median survival was 17 months, with a five years survival of 24%. Survival for ampullary tumors was 28 months with a five years survival of 32%. The median and five years survival were 14 months and 16% for bile duct cancer and 11 months and 14% for pancreatic cancer. Multivariate analysis identified tumor type (pancreas /bile duct) and lymph node dissemination as independent predictors of mortality. Conclusions: One quarter of patients experienced long term survival. Mortality predictors were tumor type and lymph node dissemination.

Lipoma gástrico gigante sintomático tratado con gastrectomía subtotal laparoscópica: caso clínico

Gastric lipoma is a rare benign gastric tumor. We report a 62-year-old man, who presented with abdominal pain, vomiting and weight loss. An upper gastrointestinal endoscopy showed a gastric antral, submucosal tumor. Abdominal ultrasound and computed tomography revealed a large antral lesion with content of high echogenicity and fat density, measuring 11 x 6 cm. The patient was treated with a laparoscopic distal subtotal gastrectomy, and a Roux-en-Y reconstruction. The patient had no postoperative morbidity, was started on a liquid diet on the third postoperative day and was discharged on the third postoperative day. The pathological study revealed a gastric lipoma with clear margins. This laparoscopic procedure represents a good alternative in the treatment of this benign gastric tumor.

Results of a Population-Based Gastric Cancer Screening Program Conducted in Chile 1996-2008

Background Chile presents the second highest stomach cancer (SC) incidence and mortality in the Americas. Since 1980 the SC mortality rate has stabilized at around 20 per 100,000, reaching a level of 18.6 per 100,000 in 2008 (males 24.4, females 12.9). Beginning in 2006 the public and the private health insurance systems cover a secondary prevention program consisting of upper gastrointestinal endoscopy (UGE) for all symptomatic cases (epigastric pain with or without symptoms of poor prognosis) aged 40 and above; it also covers medical and surgical treatments of SC detected. This prevention program has been piloted since 1996 in La Florida County (66,412 beneficiaries 40 years and older). This is the largest SC detection program conducted in Chile so far. Its goals are to decrease SC mortality through early detection and treatment. Our aim is to evaluate the 12 years of experience using this strategy. Methods Patients consulting in the primary care clinics of the study area who satisfied the above mentioned criteria were referred to the secondary level for UGE. Any suspicious lesions at UGE were biopsied and detected SC cases were referred to the base hospital for treatment. We entered all SC patients detected in the screening program from 1996 to 2008. We describe SC cases by sex, age, and staging -TNM classification system-, calculate their 5 year survival rate using the Kaplan Maier method and identify prognostic factors using the Log rank test and Cox model. Results In the study period, 11,978 individuals were referred for UGE 29.7% males (mean age 53.3: 14-93 years) and 70.3% females (mean age 52.2: 14-95 years). We identified 234 SC cases (67.1% males; 32.9% females); mean age of SC patients was 65.7 years (males 65.2 yrs, females 66.9 yrs). Detection rate of SC was 4.4% and 0.9% for males and females respectively (p<0.00001). SC staging for all patients and for males and females were: stage I 39% (35%, 45%), stage II 5% (2%, 12%), stage III 15.8% (15%, 17%), and stage IV 40% (48%, 26%). At the 5-year follow-up, 64 (27.3%) patients remained alive, 132 (56.41%) had died from SC, 12 (5.1%) died from other causes and 26 (11.1%) were censored; the 5-year survival was 41.5% (35.9% and 52.8% for males and females, p=0.002). The only prognostic factors in multivariate analysis were stage (p<0.0001) and age (p=0.001). Discussion The 5-year survival rate for SC in the program (42%) was higher than previously reported in Chile in population-based studies (11%), although the survival range of hospital-based reports has been between12-49%. We needed 212 endoscopies to detect one early cancer. It is necessary to review the current strategy to focus the UGE on populations at higher risk of early cancers -people under 50 years of age-and to include biomarkers to triage the population.

Resultados perioperatorios y sobrevida alejada de la pancreatoduodenectomía con resección vascular

Introduccion: La pancreatoduodenectomia (PDD) con reseccion vascular (RV) cuando existe invasion de la vena porta o mesenterica superior (VP-VMS) es controversial. Objetivo: Evaluar los resultados del perioperatorio y la sobrevida alejada de los pacientes sometidos a esta tecnica. Material y Metodo: Estudio retrospectivo que incluyo a los pacientes con un tumor periampular en quienes se realizo una PDD con RV entre 1990 y 2008. Se compararon los resultados del perioperatorio y de sobrevida alejada con el grupo sometido a una PDD sin RV durante el mismo periodo. Se comparo tambien la sobrevida con los pacientes no resecados. Resultados: Se realizaron 188 PDD, en 8 (4%) de estos pacientes se realizo PDD con RV (Edad: 58 ± 14 anos, Hombres: 4). La morbilidad postoperatoria para la PDD con y sin RV fue de 75% y 59% (p = ns). La mortalidad postoperatoria para los grupos con y sin RV fue de 0% y 8% (p = ns). En 6 de los 8 pacientes el diagnostico fue cancer de pancreas y en 4 se confirmo histopatologicamente la invasion de VP-VMS. La sobrevida del grupo con y sin RV no tuvo diferencia significativa (medianas 25 y 16 meses; p = ns). La sobrevida de los pacientes sometidos a una PDD con RV fue superior a los pacientes no resecados (medianas 25 y 3 meses; p = 0,0001). Conclusiones: La PDD con RV obtiene resultados perioperatorios y de sobrevida alejada comparables a una PDD sin RV. La sobrevida alcanzada con esta tecnica es ampliamente superior a la de los pacientes no resecados.

Gastrectomía laparoscópica en cancer gástrico

Introduccion: La cirugia laparoscopica ha sido incorporada como una alternativa de tratamiento curativo en cancer gastrico. El objetivo de este estudio es evaluar los resultados quirurgicos inmediatos de pacientes sometidos a gastrectomia laparoscopica por cancer gastrico incipiente e intermedio en el Hospital Clinico de la Pontificia Universidad Catolica de Chile y en el Hospital Dr. Sotero del Rio. Material y metodo: Se incluyen todos los pacientes sometidos a gastrectomia laparoscopica por cancer gastrico incipiente e intermedio (T1 - T2) en ambas instituciones. Resultados: Desde Mayo de 2005 a Diciembre del 2006, 13 pacientes fueron sometidos a gastrectomia laparoscopica, 9 hombres (70 %). Edad promedio 62+ 12 anos. El tiempo operatorio promedio fue 293 + 51 minutos, la estadia hospitalaria 7,3 + 2,8 dias. No hubo complicaciones quirurgicas. El promedio de ganglios resecados fue de 27 + 18. De acuerdo a la clasificacion TNM-AJCC, 9 pacientes se encontraban en etapa IA y 4 en etapa IB. Discusion: La gastrectomia laparoscopica es una alternativa segura en el tratamiento quirurgico del cancer gastrico incipiente e intermedio

Endoscopic submucosal dissection for early gastric cancer

endoscopic submucosal dissection for early gastric cancer introduction: Endoscopic submucosal dissection (ESD) is nowadays the standard treatment for a subgroup of early gastric cancer with low risk of lymph node metastasis. This procedure has the advantage of achieving a higher percentage of negative margins and of allowing resections of larger tumors compared with the endoscopic mucosal resection (EMR) method, being less invasive compared with surgery. aim: To analyze the postoperative outcomes, histology and overall survival of patients undergoing ESD in our center. methods: Descriptive study. Data were collected from clinical records of patients undergoing ESD from January 2008 to June 2012. results: 15 patients (8 males and 7 females, median age 70 years (45-88)) were included. The tumor was located at upper, middle and lower third in 2, 5 and 8 patients, respectively. Median tumor size was 13.5 mm (6-21). Most tumors were classified as type IIc. Among postoperative complications, there was 1 gastric bleeding and 3 gastric perforations. Hospital stay was 3 days (1-23). There was no mortality. There was one case of submucosal invasion. negative margins were achieved in 86.7%. There was one deep and one lateral positive margin, managed by surgery and re-ESD, respectively. At 16 months (7-61) of median follow-up, overall survival was 100%. Tumor recurrence was observed in one patient at 51 months, was treated by surgery. conclusion: ESD is a feasible technique in the minimally invasive management of early gastric cancer, allowing a high percentage of negative margins.