Ultrasound principles and instrumentation.

Ultrasound (US) is a fundamental and inexpensive tool both for the prompt diagnosis and for the study of diverse medical conditions. Its widespread use is partly due to the availability of US devices in the daily practice of physicians. US can be performed in real-time and is instrumental in the generation of clinical algorithms for the management of situations like trauma. It also constitutes a primary approach for the study of oncological diseases, and a guidance tool for interventions such as percutaneous drainages. In addition, and specifically for HPB surgeons, US is an essential tool in the operating room: intraoperative (either open or laparoscopic) US is necessary for the accurate determination of the stage, location, number, and margins of tumors within the liver, pancreas, or biliary tree. On another note, reading and understanding US images are skills that require time and training, which should be taught during surgical residencies. However, this is not customary in most residencies globally. This chapter offers a concise yet comprehensive elucidation of the basic principles of ultrasonography, the instruments required to perform an ultrasonic assessment of a patient, and the basic ultrasound controls.

Impact of resident involvement on patient outcomes in laparoscopic cholecystectomy of different degrees of complexity: analysis of 2331 cases.

BACKGROUND: Resident involvement in the operating room is a vital component of their medical education. Laparoscopic cholecystectomy (LC) represents the paradigmatic minimally invasive training procedure, both due to its prevalence and its different forms of complexity. We aim to evaluate whether the supervised participation of residents as operative surgeons in LC of different degrees of complexity affects postoperative outcomes in a university hospital. METHODS: This is a retrospective, single-center study that included all consecutive adult (> 18 years old) patients operated for a LC between January 1, 2012 and December 31, 2017. Each surgical procedure was recorded according to the level of complexity that we established in three types of categorization (level 1: elective surgery; level 2: cholecystitis; level 3: biliary instrumentation). Patients were clinically monitored at an outpatient clinic 7 and 30-day postoperative. Postoperative outcomes of patients operated by supervised residents (SR) and trained surgeons (TS) were compared. Postoperative complications were graded according to the Clavien-Dindo classification of surgical complications. RESULTS: A total of 2331 patients underwent LC during the study period, of whom 1573 patients (67.5%) were operated by SR and 758 patients (32.5%) by TS. There were no significant differences among age, sex, and BMI between patients operated in both groups, with the exception of ASA (P = 0.0001). Intraoperative cholangiography was performed in 100% of the patients, without bile duct injuries. There were no deaths in the 30 postoperative days. The overall complication rate was 5.70% (133 patients), with no significant differences when comparing LC performed by SR and TS (5.09 vs. 6.99%; P = 0.063). The severity rates of complications were similar in both groups (P = 0.379). Patient readmission showed a statistical difference comparing SR vs TS (0.76% vs. 2.2%; P = 0.010). The postoperative complications rate according to the complexity level of LC was not significant in level 1 and 2 for both groups. However in complexity level 3 the TS group experienced a greater rate of complications compared to the SR group (18.12% vs. 9.38%; P = 0.058). In the multivariate analysis, the participation of the residents as operating surgeons was not independently associated with an increased risk of complications (OR 1.22, 95% CI 0.84-1.77; P = 0.275), neither other risk factors like age ≥ 65 years, BMI, complexity level 2-3, or ASA ≥ 3-4. The association of another surgical procedure with the LC was an independent factor of morbidity (OR 3.85, 95% CI 2.54-5.85; P = 0.000). CONCLUSION: Resident involvement in LC with different degrees of complexity did not affect postoperative outcomes. The participation of a resident as operating surgeon is not an independent risk factor and may be considered ethical, safe, and reliable whenever implemented in the background of a residency-training program with continuous supervision and national accreditation. The sum of other procedures not related to a LC should be taken as a risk factor of morbidity.

Role of laparoscopy in the treatment of internal biliary fistulas in a high-volume center and a review of the literature.

BACKGROUND: Biliary fistulas may result as a complication of gallstone disease. According to their tract, abdominal internal biliary fistulas may be classified into cholecystobiliary and bilioenteric fistulas. Surgical treatment is challenging and requires highly trained surgeons with high preoperative suspicion. Conventional surgery is still of choice by most of the authors. However, laparoscopy is emerging as a minimally invasive alternative. We investigated the surgical approach, conversion rate, and outcomes according to the type of biliary fistula. METHODS: We retrospectively reviewed 11,130 laparoscopic cholecystectomies, 31 open cholecystectomies, and 31 surgeries for gallstone ileus at our institution from May 2007 to May 2020. We diagnosed internal biliary fistula in 73 patients and divided them into two groups according to their fistulous tract: cholecystobiliary fistula and bilioenteric fistula. We described demographic characteristics, preoperative imaging modalities, surgical approach, conversion rates, surgical procedures, and outcomes. We additionally revised the literature and compared our results with 13 studies from the past 10 years. RESULTS: There were 22 and 51 patients in the cholecystobiliary and bilioenteric groups, respectively. Our preoperative suspicion of a fistula was 80%. We started 88% of procedures by laparoscopic approach. The effectiveness of laparoscopy in the resolution of internal biliary fistula was 40% for cholecystobiliary fistula and 55% for bilioenteric fistulas. The most frequent cause for conversion to laparotomy was the difficulty to identify anatomical features, in addition to the need to perform a Roux en-Y hepaticojejunostomy. Choledocholithiasis was not associated with an increase in conversion rates. CONCLUSIONS: Laparoscopic resolution of a biliary fistula is still a matter of controversy. Despite the high conversion rates, we believe that a great number of patients benefit from this minimally invasive technique. A high preoperative suspicion and trained surgeons are vital in the treatment of internal biliary fistulas.

Teaching strategies and outcomes in 3 different times of the COVID-19 pandemic through a dynamic assessment of medical skills and wellness of surgical trainees.

BACKGROUND: The coronavirus disease 2019 pandemic had a substantial impact on surgical training programs. This study describes the teaching strategies and outcomes in 3 different times of the coronavirus disease 2019 pandemic through a dynamic assessment of medical skills and well-being of trainees. METHODS: Three surveys were administered during 2020 to general surgery residents and fellows in a university hospital in Argentina. Perceptions on the impact of coronavirus disease 2019 were described. The stress rate and risk factors were analyzed. RESULTS: The study included 124 answers. In total, 59% were men, 82% of trainees reported concerns about the loss of surgical skills in early phase 1. Time spent with academic activities increased in 94.5% of the cases. Owing to the prompt implementation of changes, by the end of 2020, 73% participated in a greater number of procedures (P = .003); personal protective equipment use related problems dropped from 40% to 14% (P = .031), and the lack of adequate spaces where trainees could express reduced from 28% to zero. Half of the trainees felt stressed, and 18% required psychological assistance; reporting problems with personal protective equipment use was identified as a risk factor (P = .012). CONCLUSION: Assessing trainees' perceptions at 3 different times of the coronavirus disease 2019 pandemic enabled the implementation of dynamic changes. The negative impact on surgical training was partially offset by the optimal use of virtual learning. Half of them felt stressed, identifying problems in the use of personal protective equipment as a predisposing factor.

Prevalence of Persistent Common Bile Duct Stones in Acute Biliary Pancreatitis Remains Stable Within the First Week of Symptoms.

BACKGROUND: Acute biliary pancreatitis (ABP) is often associated with persistent common bile duct (CBD) stones. The best strategy in terms of timing of surgery is still controversial. The aim of the current study is to describe the prevalence of persistent common bile duct (CBD) stones in ABP during the first week of symptoms at a high-volume referral center. STUDY DESIGN: Single-institution retrospective analysis of a prospectively collected database. Patients with diagnosis of ABP who underwent laparoscopic cholecystectomy (LC) between January 2009 and December 2019 were extracted. RESULTS: Two hundred thirty-one patients were included. Cholecystectomy was performed laparoscopically in 230 (99.57%) patients. Intraoperative cholangiogram was performed in all patients. Two hundred nine (90%) patients had surgery within the first 7 days. Global prevalence of persistent CBD stones during IOC was 19.91% (95% CI 14.96-25.65). No significant association between timing to surgery and presence of CBD stones was found for the first week since the initial attack (p=0.28). Prevalence of CBD stones was significantly higher after day 7 (p=0.007 and 0.005). Positive findings in preoperative MRCP are significantly related to intraoperative CBD stones (p=0.0001). Mild postoperative complications (CD I/II) were present in 21 patients (9.09%). No difference was found in morbidity between CBD stones group and non-CBD stones group (p=0.48). We observed no severe complications nor mortality. CONCLUSIONS: In patients with mild acute biliary pancreatitis, the prevalence of persistent CBD stones does not change within the first 7 days since the onset of symptoms. This fact may have major clinical relevance when deciding the optimal therapeutic strategy in this population.

Tratamiento endovascular del aneurisma esplénico incidental y en la urgencia / Endovascular treatment of incidental and emergency splenic aneurysm

Resumen Los aneurismas esplénicos verdaderos son dilataciones saculares que involucran todas las capas de la arteria esplénica. Se presentan más frecuentemente en mujeres, en el embarazo y pacientes con hipertensión portal. Son habitualmente asintomáticos y diagnosticados incidentalmente durante el estudio de otra afección abdominal. Hasta un 10% se puede presentar con ruptura, lo que supone un escenario con una alta morbilidad y mortalidad. El tratamiento de los aneurismas esplénicos es aún un tema de controversia y existen variadas modalidades terapéuticas. Presentamos dos casos de pacientes con aneurismas esplénicos: uno de ellos que se manifestó con rotura y el otro por un diagnóstico incidental. Ambos fueron resueltos mediante embolización endovascular con resultados óptimos. Esta modalidad terapéutica poco difundida para el tratamiento de aneurismas esplénicos gigantes o rotos, nos permitió resolver el cuadro de forma segura y efectiva, con mínima morbilidad y mortalidad.

Abstract True splenic aneurysms are saccular dilations of all the layers of the splenic artery, more common in women, pregnancy and portal hypertension. They are usually asymptomatic and diagnosed incidentally during the study of other abdominal diseases. Up to 10% may present with rupture, which implies a high morbidity and mortality. Treatment of splenic aneurysms is still a subject of controversy and there is a great variety of therapeutic modalities. We present two cases of patients with splenic aneurysms: one who presented with rupture and the other one incidentally diagnosed. Both were treated with endovascular embolization achieving optimal results. Although the utility of this therapy has not been assessed for giant or ruptured aneurysms, it allowed us to solve these scenarios in a secure and effective way, with minimum morbidity and mortality.

Laparoscopic transcystic common bile duct exploration as treatment for choledocholithiasis after Roux-en-Y gastric bypass.

BACKGROUND: Treatment of choledocholithiasis after Roux-en-Y gastric bypass (RYGB) is a therapeutic challenge given the altered anatomy. To overcome this technical difficulty, different modified endoscopic approaches have been described but significant morbidity accompanies these procedures. The aim of the present study is to report our experience with laparoscopic transcystic common bile duct exploration (LTCBDE) as treatment of choledocholithiasis after RYGB. METHODS: This is a retrospective cohort study of 854 consecutive patients with RYGB at a single institution between January 2007 and December 2019. Our study population focused on patients who developed biliary events after RYGB. Demographic data and perioperative parameters were compared between patients who underwent laparoscopic cholecystectomy (LC) after RYGB with (defined as Group A) and without (defined as Group B) LTCBDE. RESULTS: Fifty-seven (8.93%) patients developed a biliary event after RYGB that led to LC. Of those, 11 (19.2%) presented choledocholithiasis during intraoperative cholangiogram and were simultaneously treated with LTCBDE (Group A). Choledocholithiasis was unsuspected in the preoperative setting in 7 (63.6%) of the 11 patients. The procedure was successful in 90.9% (n = 10). Comparing Group A and B, no statistically significant differences were found regarding age, gender, length of hospital stay, and morbidity (p > 0.05). Mean operative time of Group A was 113.1 min, adding, on average, 35 min to LC (113.1 min vs 77.9 min, p = 0.004). CONCLUSIONS: LTCBDE offers an effective approach for common bile duct stones in patients who underwent RYGB. This procedure did not add significant length of hospital stay nor morbidity to laparoscopic cholecystectomy.

Long-term follow-up of Branch-Duct Intraductal Papillary Mucinous Neoplasms with negative Sendai Criteria: the therapeutic challenge of patients who convert to positive Sendai Criteria.

BACKGROUND: The management of Branch-Duct Intraductal Papillary Mucinous Neoplasm (BD-IPMN) is still controversial. Our objective was to assess the long-term follow-up (FU) of patients with "low-risk" BD-IPMN according to the Sendai-International Consensus Guidelines (ICG-I). METHODS: We retrospectively analyzed a cohort of patients with BD-IPMN and Negative Sendai-Criteria (NSC) from January 2004 to October 2019. A univariate analysis was performed to determine factors associated with conversion to Positive Sendai-Criteria (PSC) and malignancy. Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of the IGC-I were assessed for the development of malignancy. RESULTS: A total of 219 patients were selected and underwent a median 58-month FU. Thirty-seven (17%) patients developed PSC during FU including 12 (5.5%) with malignant lesions. Conversely, 182 patients (83%) did not develop malignancy. The NPV and PPV of ICG-I for malignancy were 100% and 32.4%, respectively. Among patients who developed PSC, those with cancer were >65years (OR = 3.57;p = 0.015) and had significantly higher serum CA-19-9 levels (OR = 5.27;p = 0.007). CONCLUSION: The ICG-I is a safe strategy for FU of patients with BD-IPMN. The absence of PSC exclude malignancy. Among patients who develops PSC, the risk of cancer remains low and surgery should be decided according to their surgical risk and life expectancy.

El sistema de médicos residentes: año 2020 / The medical residency system in 2020

RESUMEN En la presente revisión de los últimos años de la formación de recursos humanos en cirugía, se destaca la vigencia y la visión de futuro del discurso del Prof. Dr. Mario Brea. Cuando él define el sistema de residencias, vemos que los principios son los mismos, pero adaptados al siglo XXI: ▪▪Sistema de adiestramiento progresivo. ▪▪Programa preestablecido: modernos currículos con sistemas de evaluación integrales. ▪▪Promoción y adjudicación de responsabilidades crecientes: el cumplimiento de los milestones (o en un futuro alguna otra forma de evaluación como las Entrusted Professional Activities, EPAs). ▪▪Dirección, conducción y vigilancia estrecha: tutorización con la implementación del feedback como herramienta pedagógica. ▪▪Medio y horario de trabajo apropiados: la simulación como ambiente protegido de aprendizaje de destrezas quirúrgicas y NTS; limitación horaria para disminuir el error médico. ▪▪Investigación y docencia: estimulación de la publicación de trabajos originales desde temprano en la formación y el vínculo con residentes de niveles inferiores para crear un círculo virtuoso de forma ción profesional.

ABSTRACT The present review of the last years in the training of human resources in surgery highlights the validity and vision for the future of Prof. Dr. Mario Brea's speech. When he defines the residency system, we realize that the principles are the same, but adapted to the 21st century: ▪▪Progressive training. ▪▪Pre-established programs with modern curricula and comprehensive systems of evaluation. ▪▪Promotion and allocation of more responsibilities: compliance with Milestones (or in the future with some other type of assessment such as Entrusted Professional Activities, EPAs). ▪▪Direction, guidance and close supervision with the implementation of feedback as a pedagogical tool.Appropriate work environment and schedule: simulation as a protected environment for learning surgical and NTS skills; restrictive working hours to reduce medical error. ▪▪Research and teaching: the publication of original papers should be encouraged since the early years of training as well as the relationship with junior residents to create a virtuous circle of professional training.

Laparoscopic Transcystic Common Bile Duct Exploration in the Emergency Is as Effective and Safe as in Elective Setting.

BACKGROUND: Emergent laparoscopic transcystic common bile duct exploration (LTCBDE) has been reported to be on the increase in some institutions, reflecting the growing confidence with the technique. However, no study has focused on the outcomes of LTCBDE in the non-elective setting. The aim of this study is to investigate whether LTCBDE can be performed effectively and safely in the emergency. METHODS: This is a retrospective study of 500 consecutive patients with choledocholithiasis subjected for LTCBDE at the Hospital Italiano de Buenos Aires from January 2009 to January 2018. Procedures were classified according to the setting as emergent or elective. Demographic data and perioperative parameters were compared between groups. RESULTS: Throughout the period comprised, 500 patients were admitted for choledocholithiasis and gallstones. A single-step treatment combining LTCBDE and laparoscopic cholecystectomy was attempted: 211 (42.2%) were performed electively and the 289 (57.8%) as an emergency. There was no significant difference in the success rate of LTCBDE (93.9% versus 93.8%, p = 0.975) for the two groups. The operative time was slightly longer in the emergency group (122 ± 63 versus 106 ± 53 min, p = 0.002). Postoperative recovery was slower in the emergency group, as reflected by a higher rate of prolonged postoperative stay (21.1% vs 5.7%, p < .001). The rates of postoperative complications were similar between groups (2.8% vs 5.9%, p = 0.109). CONCLUSION: Emergent LTCBDE can be performed with equivalent efficacy and morbidity when compared to an elective procedure. Patients undergoing emergent procedures have longer procedures and hospital stays.

Acute Pancreatitis After Laparoscopic Transcystic Common Bile Duct Exploration: An Analysis of Predisposing Factors in 447 Patients.

INTRODUCTION: In laparoscopic transcystic common bile duct exploration (LTCBDE), the risk of acute pancreatitis (AP) is well recognized. The present study assesses the incidence, risk factors, and clinical impact of AP in patients with choledocholithiasis treated with LTCBDE. METHODS: A retrospective database was completed including patients who underwent LTCBDE between 2007 and 2017. Univariate and multivariate analyses were performed by logistic regression. RESULTS: After exclusion criteria, 447 patients were identified. There were 70 patients (15.7%) who showed post-procedure hyperamylasemia, including 20 patients (4.5%) who developed post-LTCBDE AP. Of these, 19 were edematous and one was a necrotizing pancreatitis. Patients with post-LTCBDE AP were statistically more likely to have leukocytosis (p < 0.004) and jaundice (p = 0.019) before surgery and longer operative times (OT, p < 0.001); they were less likely to have incidental intraoperative diagnosis (p = 0.031) or to have biliary colic as the reason for surgery (p = 0.031). In the final multivariate model, leukocytosis (p = 0.013) and OT (p < 0.001) remained significant predictors for AP. Mean postoperative hospital stay (HS) was significantly longer in AP group (p < 0.001). CONCLUSION: The risk of AP is moderate and should be considered in patients with preoperative leukocytosis and jaundice and exposed to longer OT. AP has a strong impact on postoperative HS.

Protocol for extended antibiotic therapy after laparoscopic cholecystectomy for acute calculous cholecystitis (Cholecystectomy Antibiotic Randomised Trial, CHART).

INTRODUCTION: Acute calculous cholecystitis represents one of the most common complications of cholelithiasis. While laparoscopic cholecystectomy is the standard treatment in mild and moderate forms, the need for antibiotic therapy after surgery remains undefined. The aim of the randomised controlled Cholecystectomy Antibiotic Randomised Trial (CHART) is therefore to assess if there are benefits in the use of postoperative antibiotics in patients with mild or moderate acute cholecystitis in whom a laparoscopic cholecystectomy is performed. METHODS AND ANALYSIS: A single-centre, double-blind, randomised trial. After screening for eligibility and informed consent, 300 patients admitted for acute calculus cholecystitis will be randomised into two groups of treatment, either receiving amoxicillin/clavulanic acid or placebo for 5 consecutive days. Postoperative evaluation will take place during the first 30 days. Postoperative infectious complications are the primary end point. Secondary end points are length of hospital stay, readmissions, need of reintervention (percutaneous or surgical reinterventions) and overall mortality. The results of this trial will provide strong evidence to either support or abandon the use of antibiotics after surgery, impacting directly in the incidence of adverse events associated with the use of antibiotics, the emergence of bacterial resistance and treatment costs. ETHICS AND DISSEMINATION: This study and informed consent sheets have been approved by the Research Projects Evaluating Committee (CEPI) of Hospital Italiano de Buenos Aires (protocol N° 2111). RESULTS: The results of the trial will be reported in a peer-reviewed publication. TRIAL REGISTRATION NUMBER: NCT02057679.

Intraoperative management and repair of bile duct injuries sustained during 10,123 laparoscopic cholecystectomies in a high-volume referral center.

BACKGROUND: Bile duct injury (BDI) remains the most serious complication of laparoscopic cholecystectomy (LC). The best strategy in terms of timing of repair is still controversial. The purpose of the current study is to review the experience in the intraoperative repair of bile duct injuries sustained during LC at a high-volume referral center. STUDY DESIGN: Single-institution retrospective analysis of a prospectively collected database. Patients with diagnosis of BDI sustained during LC between October 1991 and November 2010 were extracted. RESULTS: Among 10,123 LC performed during the study period, 19 patients had a BDI sustained during the procedure. Intraoperative cholangiography was routinely used. Bile duct injury was diagnosed intraoperatively in 17 patients (89.4%). Mean age was 56.4 years (range 18 to 81 years) and 15 patients were women (88%). According to the Strasberg classification of BDI, there were 3 type C lesions, 12 type D lesions, and 2 type E2 lesions. There were no associated vascular injuries. Twelve cases (71%) were converted to open surgery. The repairs included 10 primary biliary closures, 4 Roux-en-Y hepaticojejunostomies, 2 end to end anastomosis, and 1 laparoscopic transpapillary drainage. Postoperative complications occurred in 5 patients (29.4%). During the follow-up period, early biliary strictures developed in 2 patients (11.7%) and were treated by percutaneous dilation and a Roux-en-Y hepaticojejunostomy with satisfactory long-term results. CONCLUSIONS: The current series represents one of the largest single-center experiences in terms of intraoperative repair of BDI sustained during LC. The results suggest that a high level of intraoperative diagnosis is possible, where intraoperative cholangiography is a useful tool. The intraoperative repair of BDI sustained during LC by experienced hepatobiliary surgeons either by open or laparoscopic approach appears of paramount importance to assure optimal results.

Modified Makuuchi incision for foregut procedures.

The Makuuchi or J incision completely exposes the liver and right-sided retroperitoneal organs. The modified Makuuchi incision also achieves a superb en face view of critical structures, including the hepatocaval junction and the esophageal hiatus, but does not divide the intercostal muscles, thus reducing muscle atrophy and postoperative pain. This incision also offers significant advantages over other incisions commonly used in foregut surgery. We describe herein the use of the modified Makuuchi incision for foregut procedures, with particular emphasis on strategic retractor placement.

Two-surgeon technique of parenchymal transection contributes to reduced transfusion rate in patients undergoing major hepatectomy: analysis of 1,557 consecutive liver resections.

BACKGROUND: Blood transfusions are an independent risk factor for adverse outcomes after hepatectomy. In-hospital transfusions are still reported in one third of patients in major series. Data on factors affecting blood transfusions in large series of liver resection are limited. The aim of this study was to evaluate factors predictive of blood transfusion in hepatectomies performed at a tertiary referral center. METHODS: Records of 1,477 patients who underwent 1,557 liver resections between 1998 and 2007 were reviewed. Multivariate analysis of risk factors for red cell transfusion was performed. RESULTS: Median intra-operative blood loss was 250 cc, and 30-day peri-operative red cell transfusion rate was 27%. On multivariate analysis, factors that significantly predicted increased red cell transfusion rates were female sex, pre-operative hematocrit<30%, platelet count<100,000/mm3, simultaneous resection of other organs, major hepatic resection, use of the Pringle maneuver, and tumors>10 cm. Parenchymal transection technique was an independent risk factor for perioperative red cell transfusion; the usage of the 2-surgeon technique (combined saline-linked cautery and ultrasonic dissection) was associated with a lower transfusion rate than other techniques, including ultrasonic dissection alone, finger fracture, and stapling (P<.001). CONCLUSION: Although most factors that affect the red cell transfusion rate for liver resection are patient- or tumor-related, the parenchymal transection technique is under the surgeon's control. The decrease in transfusion rate associated with the use of the 2-surgeon technique emphasizes the important role of the hepatobiliary surgeon in determining outcomes after liver resection.

Association of computed tomography morphologic criteria with pathologic response and survival in patients treated with bevacizumab for colorectal liver metastases.

CONTEXT: The standard criteria used to evaluate tumor response, the Response Evaluation Criteria in Solid Tumors (RECIST), were developed to assess tumor shrinkage after cytotoxic chemotherapy and may be limited in assessing response to biologic agents, which have a cytostatic mechanism of action. OBJECTIVE: To validate novel tumor response criteria based on morphologic changes observed on computed tomography (CT) in patients with colorectal liver metastases treated with bevacizumab-containing chemotherapy regimens. DESIGN, SETTING, AND PATIENTS: A total of 234 colorectal liver metastases were analyzed from 50 patients who underwent hepatic resection after preoperative chemotherapy that included bevacizumab at a comprehensive US cancer center from 2004 to 2007; date of last follow-up was March 2008. All patients underwent routine contrast-enhanced CT at the start and end of preoperative therapy. Three blinded, independent radiologists evaluated images for morphologic response, based on metastases changing from heterogeneous masses with ill-defined margins into homogeneous hypoattenuating lesions with sharp borders. These criteria were validated with a separate cohort of 82 patients with unresectable colorectal liver metastases treated with bevacizumab-containing chemotherapy. MAIN OUTCOME MEASURES: Response determined using morphologic criteria and RECIST was correlated with pathologic response in resected liver specimens and with patient survival. RESULTS: Interobserver agreement for scoring morphologic changes was good among 3 radiologists (kappa, 0.68-0.78; 95% confidence interval [CI], 0.51-0.93). In resected tumor specimens, the median (interquartile range [IQR]) percentages of residual tumor cells for optimal morphologic response was 20% (10%-30%); for incomplete response, 50% (30%-60%); and no response, 70% (60%-70%; P < .001). With RECIST, the median (IQR) percentages of residual tumor cells were for partial response 30% (10%-60%); for stable disease, 50% (20%-70%); and for progressive disease, 70% (65%-70%; P = .04). Among patients who underwent hepatic resection, median overall survival was not yet reached with optimal morphologic response and 25 months (95% CI, 20.2-29.8 months) with incomplete or no morphologic response (P = .03). In the validation cohort, patients with optimal morphologic response had median overall survival of 31 months (95% CI, 26.8-35.2 months) compared with 19 months (95% CI, 14.6-23.4 months) with incomplete or no morphologic response (P = .009). RECIST did not correlate with survival in either the surgical or validation cohort. CONCLUSION: Among patients with colorectal liver metastases treated with bevacizumab-containing chemotherapy, CT-based morphologic criteria had a statistically significant association with pathologic response and overall survival.

Laparoscopic resection for liver tumors: initial experience in a single center.

BACKGROUND: Laparoscopic liver resections are 1 of the most complex procedures in hepatobiliary surgery. During the last 20 years, laparoscopic liver surgery has had an important development in specialized centers. OBJECTIVE: To describe the initial experience in laparoscopic liver resection for benign and malignant tumors, to assess its indications and outcomes, and to describe technical aspects of these resections. METHODS: Review of the records of 28 patients who underwent laparoscopic liver resection between November 2000 and November 2007. Analysis of the data regarding preoperative management and postoperative outcomes. RESULTS: Twenty-six liver resections were performed laparoscopically (20 purely laparoscopic, 3 hand assisted, and 3 hybrid technique) and 2 were converted to open surgery. The laparoscopic approach was attempted in 6% (28 out of 459) of the liver resections carried out in the analyzed period. Indications for resection were: benign tumors in 22 patients (78%) and malignant tumors in 6 patients (22%). Resections were minor in 27 patients (96%) and major in 1 patient (4%). Pringle maneuver was performed in 14 patients (50%). Margins were negative in all the cases. Mean operative time was 170 minutes (range 70 to 350), and the mean length of stay was 3 days (range 1 to 6). Mortality rate was 0%. Only 2 patients (7%) had postoperative minor complications (self-limited bile leaks). CONCLUSIONS: In selected patients with benign and malignant liver tumors, laparoscopic liver resections can be safely performed. This procedure must be carried out by the surgeons trained in both the hepatobiliary and laparoscopic surgery.

Portal vein embolization in hilar cholangiocarcinoma.

In patients with hilar cholangiocarcinoma, extended hepatectomy and caudate lobe resection are often performed to achieve an R0 resection. In patients whose standardized future liver remnant is less than or equal to 20% of total liver volume, portal vein embolization (PVE) should be performed. In patients with biliary dilatation of the future liver remnant, a biliary drainage catheter should be placed before PVE. If the planned surgery is an extended right hepatectomy, segment 4 branch embolization improves the hypertrophy of segments 2 and 3. In high-volume centers, PVE can be safely performed; it increases the resectability rate and results in the same survival rates as those in patients who undergo resection without PVE.