Disección endoscópica submucosa para el tratamiento de neoplasias incipientes del tubo digestivo: experiencia en un centro universitario de alto volumen / Experience with endoscopic submucosal dissection for the treatment of early neoplasms of the digestive tract

Background: Endoscopic submucosal dissection (ESD) allows en-bloc resection of early gastro-intestinal neoplasms (EGIN) with healing potential. Aim: To describe the results of patients treated with ESD for EGIN by our team. Patients and Methods: Descriptive study of patients with EGIN who underwent ESD with curative intention between January 2008 and March 2020. Results: One hundred thirty-two ESD were performed in 127 patients. 77% were gastric lesions, 14% colorectal, 8% esophageal and 1% duodenal. En-bloc resection was achieved in 98.4% of ESDs. Eighty eight percent of patients met curative standards. Overall, cancer-specific, and recurrence-free survival were 95%, 100% and 98% respectively. Conclusions: ESD allows en-bloc resections with curative potential in selected patients, but with a significant reduction in morbidity and mortality and less impact on quality of life. Our results suggest the feasibility to perform ESD in our country with results comparable to those reported in the literature.

Risk factors for severe postoperative complications after gastrectomy for gastric and esophagogastric junction cancers / Fatores de risco para complicações pós-operatórias graves após gastrectomia por câncer do estômago e junção esofagogástrica

ABSTRACT Background: Gastrectomy is the main treatment for gastric and Siewert type II-III esophagogastric junction (EGJ) cancer. This surgery is associated with significant morbidity. Total morbidity rates vary across different studies and few have evaluated postoperative morbidity according to complication severity. Aim: To identify the predictors of severe postoperative morbidity. Methods: This was a retrospective cohort study from a prospective database. We included patients treated with gastrectomy for gastric or EGJ cancers between January 2012 and December 2016 at a single center. Severe morbidity was defined as Clavien-Dindo score ≥3. A multivariate analysis was performed to identify predictors of severe morbidity. Results: Two hundred and eighty-nine gastrectomies were performed (67% males, median age: 65 years). Tumor location was EGJ in 14%, upper third of the stomach in 30%, middle third in 26%, and lower third in 28%. In 196 (67%), a total gastrectomy was performed with a D2 lymph node dissection in 85%. Two hundred and eleven patients (79%) underwent an open gastrectomy. T status was T1 in 23% and T3/T4 in 68%. Postoperative mortality was 2.4% and morbidity rate was 41%. Severe morbidity was 11% and was mainly represented by esophagojejunostomy leak (2.4%), duodenal stump leak (2.1%), and respiratory complications (2%). On multivariate analysis, EGJ location and T3/T4 tumors were associated with a higher rate of severe postoperative morbidity. Conclusion: Severe postoperative morbidity after gastrectomy was 11%. Esophagogastric junction tumor location and T3/T4 status are risk factors for severe postoperative morbidity.

RESUMO Raciona l: A gastrectomia é o tratamento principal para o câncer de junção esofagogástrica (EGJ) e Siewert tipo II-III. Ela está associada à morbidade significativa. As taxas de morbidade total variam entre os diferentes estudos e poucos avaliaram a morbidade pós-operatória de acordo com a gravidade da complicação. Objetivo: Identificar os preditores de morbidade pós-operatória grave. Métodos: Este foi um estudo de coorte retrospectivo de um banco de dados prospectivo. Foram incluídos pacientes tratados com gastrectomia para câncer gástrico ou EGJ em um único centro. A morbidade severa foi definida como escore de Clavien-Dindo ≥3. Análise multivariada foi realizada para identificar preditores de morbidade grave. Resultados: Duzentos e oitenta e nove gastrectomias foram realizadas (67% homens, mediana de idade: 65 anos). A localização do tumor foi EGJ em 14%, o terço superior do estômago em 30%, o terço médio em 26% e o terço inferior em 28%. Em 196 (67%), foi realizada gastrectomia total com dissecção de linfonodos D2 em 85%. Duzentos e onze pacientes (79%) foram submetidos à gastrectomia aberta. O estado T foi T1 em 23% e T3/T4 em 68%. A mortalidade pós-operatória foi de 2,4% e a taxa de morbidade foi de 41%. A morbidade severa foi de 11% e foi representada principalmente por fístula esofagojejunal (2,4%), fístula duodenal (2,1%) e complicações respiratórias (2%). Na análise multivariada, a localização do EGJ e os tumores T3/T4 foram associados com maior morbidade pós-operatória grave. Conclusão: Morbidade pós-operatória severa após gastrectomia foi de 11%. A localização do tumor na junção esofagogástrica e o estado T3/T4 são fatores de risco para a morbidade pós-operatória grave.

Survival and perioperative morbidity of totally laparoscopic versus open gastrectomy for early gastric cancer: analysis from a single latin american centre / Comparação da sobrevida e morbidade perioperatória da gastrectomia totalmente laparoscópica vs. laparotômica para tratamento do câncer gástrico precoce em um centro latino-americano

ABSTRACT Background: Laparoscopic gastrectomy has numerous perioperative advantages, but the long-term survival of patients after this procedure has been less studied. Aim: To compare survival, oncologic and perioperative outcomes between completely laparoscopic vs. open gastrectomy for early gastric cancer. Methods: This study was retrospective, and our main outcomes were the overall and disease-specific 5-year survival, lymph node count and R0 resection rate. Our secondary outcome was postoperative morbidity. Results: Were included 116 patients (59% men, age 68 years, comorbidities 73%, BMI 25) who underwent 50 laparoscopic gastrectomies and 66 open gastrectomies. The demographic characteristics, tumour location, type of surgery, extent of lymph node dissection and stage did not significantly differ between groups. The overall complication rate was similar in both groups (40% vs. 28%, p=ns), and complications graded at least Clavien 2 (36% vs. 18%, p=0.03), respiratory (9% vs. 0%, p=0.03) and wound-abdominal wall complications (12% vs. 0%, p=0.009) were significantly lower after laparoscopic gastrectomy. The lymph node count (21 vs. 23 nodes; p=ns) and R0 resection rate (100% vs. 96%; p=ns) did not significantly differ between groups. The 5-year overall survival (84% vs. 87%, p=0.31) and disease-specific survival (93% vs. 98%, p=0.20) did not significantly differ between the laparoscopic and open gastrectomy groups. Conclusion: The results of this study support similar oncologic outcome and long-term survival for patients with early gastric cancer after laparoscopic gastrectomy and open gastrectomy. In addition, the laparoscopic approach is associated with less severe morbidity and a lower occurrence of respiratory and wound-abdominal wall complications.

RESUMO Racional: A gastrectomia laparoscópica tem numerosas vantagens perioperatórias, mas a sobrevivência em longo prazo após este procedimento tem sido menos estudada. Objetivo: Comparar resultados de sobrevivência, oncológica e perioperatória entre a gastrectomia completamente laparoscópica vs. aberta para câncer gástrico precoce. Método: Este estudo foi retrospectivo e os principais resultados foram a sobrevivência global e específica de cinco anos, contagem de linfonodos e taxa de ressecção R0. Resultado secundário foi a morbidade pós-operatória. Resultados: Foram incluídos 116 pacientes (59% homens, idade 68 anos, comorbidades 73%, IMC 25) que foram submetidos a 50 gastrectomias laparoscópicas e 66 gastrectomias abertas. As características demográficas, a localização do tumor, o tipo de operação, a extensão da dissecção dos linfonodos e do estágio não diferiram significativamente entre os grupos. A taxa geral de complicações foi semelhante em ambos os grupos (40% vs. 28%, p=ns) e complicações classificadas Clavien 2 (36% vs. 18%, p=0,03), respiratórias (9% vs. 0%, p=0,03) e as da parede abdominal (12% vs. 0%, p=0,009) foram significativamente menores após a gastrectomia laparoscópica. A contagem de linfonodos (21 contra 23, p=ns) e a taxa de ressecção R0 (100% vs. 96%; p=ns) não diferiram significativamente entre os grupos. A sobrevida global de cinco anos (84% vs. 87%, p=0,31) e a sobrevida específica (93% vs. 98%, p=0,20) não diferiram significativamente entre os grupos de gastrectomia laparoscópica e aberta. Conclusão: Estes resultados suportam resultados oncológicos similares e sobrevida em longo prazo para pacientes com câncer gástrico precoce após gastrectomia laparoscópica e gastrectomia aberta. Além disso, a abordagem laparoscópica está associada com morbidade menos grave e menor ocorrência de complicações respiratórias e da parede abdominal.

Experiencia inicial con esofagectomia mínimamente invasiva transtorácica en posición semiprono por cáncer esofágico / Initial experience with minimally invasive transtoraxic esophagectomy in semiprone position for esophageal cancer

Resumen Introducción El tratamiento quirúrgico del cáncer esofágico se asocia a una alta morbimortalidad. El abordaje mínimamente invasivo se ha introducido con el objetivo de disminuir la morbilidad postoperatoria. Objetivo Describir la técnica y los resultados de la esofagectomía mínimamente invasiva (EMI) transtorácica en posición semiprono. Métodos Estudio de cohorte descriptivo. Se incluyeron pacientes con una EMI electiva por cáncer entre abril de 2013 y mayo de 2017. Se registraron variables demográficas, perioperatorias, anatomía patológica y la sobrevida. Resultados Incluimos 33 pacientes (24 hombres, edad 69 años, 91% con comorbilidades). La ubicación predominante del tumor fue en los tercios medio e inferior del esófago (90%). Quince (45%) pacientes recibieron neoadyuvancia. No existieron casos de conversión a toracotomías. La reconstrucción se realizó con estómago en un 93%. Se realizó anastomosis cervical en 66% y torácica en 30%. El tiempo operatorio fue de 420 (330-570) minutos y el sangrado de 200 (20-700) cc. La mortalidad a 90 días fue de 0%. La morbilidad global fue de 78%, se registró un 15% de neumonía y un 9% requirió una reoperación. La estadía hospitalaria fue de 23 (11-81) días. La histología fue carcinoma escamoso en 51% y adenocarcinoma en 45%. Los márgenes fueron RO en 87%. El recuento ganglionar alcanzó 30 (9-45) ganglios. La sobrevida global a 2 años es 68%. Conclusión Los resultados preliminares de esta técnica son favorables; sin ningún caso de mortalidad postoperatoria. Los resultados oncológicos demuestran un alto porcentaje de cirugía RO y adecuado recuento ganglionar.

Introduction Surgical treatment of esophageal cancer is associated with high morbidity and mortality. The minimally invasive approach has been introduced with the aim of reducing postoperative morbidity. Aim To describe the surgical technique and the results of transthoracic minimally invasive esophagectomy (MIE) in semiprone position. Material and Methods Descriptive cohort study. Patients with an elective MIE for cancer were included between April 2013 and May 2017. Demographic, perioperative, pathology and survival variables were recorded. Results We included 33 patients (24 men, age 69 years, 91% with comorbidities). The predominant location of the tumor was in the middle and lower thirds of the esophagus (90%). Fifteen (45%) patients received neoadjuvant treatment. There were no cases of conversion to thoracotomy. The reconstruction was performed with stomach in 93%. Cervical anastomosis was performed in 66% and thoracic anastomosis in 30%. The operative time was 420 (330-570) minutes and bleeding 200 (20-700) cc. The 90-day mortality rate was 0%. Overall morbidity was 78%, there was a 15% occurrence of pneumonia and 9% required a reoperation. The hospital stay was 23 (11-81) days. The histology was squamous carcinoma in 51% and adenocarcinoma in 45%. Margins were RO at 87%. The lymph node count reached 30 (9-45) lymph nodes. Overall 2-year survival is 68%. Conclusion The preliminary results of this technique are favorable, without any case of postoperative mortality. The oncological results demonstrate a high percentage of RO surgery and adequate lymph node count.

Gastrectomía totalmente laparoscópica por neoplasias gástricas: Experiencia en un centro público / Totally laparoscopic gastrectomy for the treatment of gastric tumors

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.

Experiencia de 18 años de cirugía de obesidad en la Pontificia Universidad Católica de Chile / Results of bariatric surgery. Experience over 18 years

Background: Bariatric surgery is the gold-standard treatment for morbid obesity because it has low morbidity rates in high-volume centers and generates long term sustained weight loss. Aim: To describe our experience in bariatric surgery since the creation of our bariatric program in 1992. Material and Methods: Retrospective analysis of all patients subjected to bariatric surgery from 1992 to December 2010. Data was obtained from the electronic institutional registry. The Procedures per-formed were open and laparoscopic Roux-en-Ygastric bypass (BPGA and BPGL, respectively), laparoscopic adjustable gastric band (BGAL) and laparoscopic sleeve gastrectomy (GML). Results: A total of 4943 procedures were performed, 768 (16%) BPGA, 2558 (52%) BPGL, 199 (4%) BGAL and 1418 (29%) GML. The number of procedures progressively increased, from 100 cases in 2000 to over 700 cases in 2008. Proportion of femóles and preoperative mean body mass Índex fluctuated between 69 and 79% and 35 and 43 kg/m², respectively, among the different procedures. Early and late complications fluctuated between Oto 1% (higher on BPGA) and 3 to 32.7% (higher on BGAL), respectively. The excess weight lost atfiveyears was 76.1 % in BPGA, 92.5%o in BPGL and 53.7% in BGAL. The figure for GML at three years was 73.7%. Conclusions: The complication rates ofthis series of patients are similar to those reported in large series abroad. BPGL is still the most effective procedure; however GML is an attractive alternative for less obese patients.

Resultados actuales de la pancreatoduodenectomía para el tratamiento de los tumores periampulares y análisis de factores pronósticos de sobrevida / Results of pancreaticoduodenectomy in the treatment of periampullary tumors

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 percent and a pancreatogastric anastomosis was used in 94 percent of cases. Morbidity was 62 percent and postoperative mortality was 5.5 percent. Pancreatic cancer was the most frequent pathological finding in 41 percent, followed by ampullary cancer in 28 percent and distal bile duct cancer in 16 percent. Median survival was 17 months, with a five years survival of 24 percent. Survival for ampullary tumors was 28 months with a five years survival of 32 percent. The median and five years survival were 14 months and 16 percent for bile duct cancer and 11 months and 14 percent 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.

Resultados del tratamiento quirúrgico de las metástasis hepáticas por cáncer colorrectal / Outcome of surgical treatment of liver metastasis from colorectal cancer

Background: Surgical resection is the only treatment associated with long-term cure in patients with liver metastasis from colorectal cancer, achieving a 30% to 40% five years survival. Aim: To evaluate the results of liver resection for metastatic colorectalcancer in our centre. Patients and methods: Retrospective study. Epidemiological, perioperative and follow up data of patients undergoing liver resection for metastatic colorectalcancer between January 1990 and July 2007 were assessed. We compared the results between two periods; period 1 (1990-1997) and period 2 (1998-2007). Results: Sixty six patients aged61±12 years (46 males) underwent 75 resections. An anatomical excision was performed in 54 (72%) cases, a right hepatectomy in 18, an extended right hepatectomy in 11, a left hepatectomy in 1, and a segmentectomy in 24. In 24 (32%) patients the liver resection wassimultaneous with the colorectal cancer resection. Operative time was 221±86 min. Hospital stay was 11±5 days. Postoperative morbidity was 35% and surgical mortality was 0%. Resectionmargin was free of tumor in 53 (80%) patients. Five years overall and hepatic disease-free survival was 38% and 23%, respectively. In period 2, more anatomical resections than in period1 were performed (77% and 55%, respectively, p =0.04), without an increase in complications (35% and 34%, respectively; p =ns), but with a better five years survival (45% and 21%, respectively, p =0.04). Conclusions: Five years survival for excision of liver metastatic colorectal cancer in our center is similar to that reported abroad. During the second period there has been a trend toward more extensive resections which was associated with a better survival, without an increase in complications or mortality.

Rendimiento de la colangiografía por resonancia magnética en el diagnóstico de coledocolitiasis / Accuracy of magnetic resonance cholangiopancreatography for the diagnosis of common bile duct stones

Magnetic resonance cholangiopancreatography MRCP) is a non-invasive diagnostic method for choledocholithiasis. Aim: To evaluate the results of MRCP in the diagnosis of choledocholithiasis. Patients and methods: Retrospective review of MRCP reports performed between October 2001 and December 2004. We included patients with suspected choledocholithiasis who were studied with MRCP and some other confirmatory test such as endoscopic retrograde cholangiopancreatography ERCP), surgical common bile duct exploration or transcystic colangiography TC). Results: One hundred and twenty five patients aged 58±20 years 70 females) were included. In 54 patients 43 percent) we compared the results of MRCP with the findings of surgical common bile duct exploration or TC and in 71 57 percent) we did so with ERCP. MRCP suggested choledocholithiasis in 93 patients and in 32 it was negative. Eighty six 67 percent) patients had choledocholithiasis according to TC or ERCP, including 3 patients who had a negative MRCP. Therefore the sensibility was 97 percent, specificity 74 percent positive predictive value 89 percent, negative predictive value 90 percent and accuracy of MRCP was 90 percent for the diagnosis of choledocholithiasis. Conclusions: MRCP has a high accuracy for the diagnosis of choledocholithiasis.

El índice de oxigenación es un mejor indicador del intercambio gaseoso que la relación PaO2: FiO2 en pacientes adultos sometidos a ventilación mecánica / Oxygenation index is a better indicator of gaseous interchange than PaO2/FiO2 ratio in adult patients receiving mechanical ventilation

Oxygenation Index (Oxlx = MAP x 100 / Pa/FiO2) has been widely used to assess gas exchange in pediatric patients. We evaluated Oxlx and PaO2:FiO2 ratio (Pa/FiO2) in adults patients under Mechanical Ventilation (MV). Seventy-two patients (39 M, 33 F, 53 ± 21 yo, APACHE II 17 ± 7) required MV for 4 ± 3 days (1-18), of which 17 died (24 per cent). Arterial blood gases along FiO2, PEEP and mean airway pressure (MAP), to calculate Pa/FiO2 and Oxlx, and static toraco-pulmonar Compliance (Cst) were measured on a daily basis. Compliance had a good correlation with Oxlx (r = -0.7, p = 0.0001) and Pa/FiO2 (r = 0.5, p = 0.0001). Correlation between Cst and Oxlx improved (r = 0.8, p = 0.0001) when considering only Acute Respiratory Failure patients (ARF, n = 37). Mortality in ARF patients was related to a greater MAP, lower Cst and a worst Oxlx but not Pa/FiO2. Patients who fulfilled ARDS criteria had the worst Pa/FiO2, Oxlx and Cst values. In contrast, no relationship could be observed between Cst and gas exchange markers in neurologic patients (n = 22), or between these parameters and mortality. Oxygenation Index seems to be a better marker of gas exchange than Pa/FiO2 in adults patients under MV. It had a better relationship with the impairment in pulmonary function and mortality in ARF patients.