Management of early gastrointestinal neuroendocrine neoplasms

Neuroendocrine neoplasms (NENs) of the stomach, duodenum, appendix or rectum that are small (≤ 1 cm) and well differentiated can be considered “early” tumors, since they generally have a (very) good prognosis. In the new WHO classification of 2010, these neoplasms are called neuroendocrine tumors/ carcinoids (NETs), grade (G) 1 or 2, and distinguished from poorly differentiated neuroendocrine carcinomas (NECs), G3. NETs are increasing, with a rise in the age-adjusted incidence in the U.S.A. by about 700 % in the last 35 years. Improved early detection seems to be the main reason for these epidemiological changes. Both the better general availability of endoscopy, and imaging techniques, have led to a shift in the discovery of smaller-sized (≤ 10-20 mm) intestinal NETs/carcinoids and earlier tumor stages at diagnosis. Endoscopic screening is therefore effective in the early diagnosis, not only of colorectal adenocarcinomas, but also of NETs/carcinoids. Endoscopic removal, followed up with endoscopic surveillance is the treatment of choice in NETs/carcinoids of the stomach, duodenum and rectum that are ≤ 10 mm in size, have a low proliferative activity (G1), do not infiltrate the muscular layer and show no angioinvasion. In all the other intestinal NENs, optimal treatment generally needs surgery and/or medical therapy depending on type, biology and stage of the tumor, as well as the individual situation of the patient.

"Nil per oral after midnight": Is it necessary for clear fluids?

Fasting before general anaesthesia aims to reduce the volume and acidity of stomach contents, thus reducing the risk of regurgitation and aspiration. Recent guidelines have recommended a shift in fasting policies from the standard ‘nil per oral from midnight’ to a more relaxed policy of clear fluid intake a few hours before surgery. The effect of preoperative oral administration of 150 ml of water 2 h prior to surgery was studied prospectively in 100 ASA I and II patients, for elective surgery. Patients were randomly assigned to two groups. Group I (n = 50) was fasting overnight while Group II (n = 50) was given 150 ml of water 2 h prior to surgery. A nasogastric tube was inserted after intubation and gastric aspirate was collected for volume and pH. The gastric fluid volume was found to be lesser in Group II (5.5 ± 3.70 ml) than Group I (17.1 ± 8.2 ml) which was statistically significant. The mean pH values for both groups were similar. Hence, we conclude that patients not at risk for aspiration can be allowed to ingest 150 ml water 2 h prior to surgery.

Disinfection of the Access Orifice in NOTES: Evaluation of the Evidence Base

Introduction. Appropriate prevention of infection is a key area of research in natural orifice translumenal endoscopic surgery (NOTES), as identified by the Natural Orifice Surgery Consortium for Assessment and Research (NOSCAR). Methods. A review of the literature was conducted evaluating the evidence base for access orifice preparation/treatment in NOTES procedures in the context of infectious complications. Recommendations based on the Oxford Centre for Evidence-Based Medicine guidelines were made. Results. The most robust evidence includes several experimental randomised controlled trials assessing infectious complications in the transgastric approach to NOTES. Transvaginal procedures are long established for accessing the peritoneal cavity following disinfection with antiseptic. Only experimental case series for transcolonic and transvesical approaches are described. Conclusion. Grade C recommendation requiring no preoperative preparation can be made for the transgastric approach. Antiseptic irrigation is recommended for transvaginal (grade C) NOTES access, as is current practice. Further human trials need to be conducted to corroborate the current evidence base for transgastric closure. It is important that future trials are conducted in a methodologically robust fashion, with emphasis on clinical outcomes and standardisation of enterotomy closure and postoperative therapy.

Metastases to the pancreas: the experience of a high volume center and a review of the literature

BACKGROUND

Metastasis to the pancreas (PM) is uncommon. Several types of cancers were reported to metastasize to the pancreas. Surgery is advocated in selected patients when technically feasible and if the patient can be rendered disease free.

METHODS

A retrospective review of PM patients at the University of Cincinnati Pancreas Database was performed over a 7-year time period.

RESULTS

Twenty patients with a median age of 62.5 years were identified. Fifteen patients (75%) were males and (50%) presented with abdominal pain. Nine patients (45.0%) were offered surgical resection, distal pancreatectomy was the most common procedure (n = 4, 44.4%). The commonest pathology was RCC (60%), followed by lung (20%), colon (15%), and breast (5%). Median disease free interval (DFI) was 96 months for RCC, 7 months for other pathologies. Median survival was 19 months for RCC, 8.5 months for other pathologies. Based on DFI, short DFI patients (≤12 months) had worse prognosis (2-year survival of 40%), as opposed to (2-year survival of 80%) in longer DFI patients (P = 0.01). RCC patients with a DFI longer than 94 months had a better survival (P = 0.01). Survival of resected PM tended to be longer than non-resected PM (P = 0.11).

CONCLUSIONS

PM from RCC carries a consistently favorable prognosis compared to other pathologies. Surgical resection of PM is a safe and viable option, and, in selected patients, may improve survival. However, a period of expectant management in patients with short DFI may be considered.

Metastasis to the pancreas and the spleen: an increasing diagnostic and therapeutic challenge

We have reviewed the electronic biopsies database files of the Department of Surgical Pathology, Fundación Jiménez Díaz in Madrid (Spain). In this time period (1998–2010) we have found 3 pancreatic metastasis and 5 splenic metastasis. Two of the pancreatic metastases were originated in clear cell renal cell carcinomas. The last pancreatic metastasis was from a malignant cutaneous melanoma diagnosed and treated 8 years before. As for splenic metastasis, three of them were diagnosed during the abdominal surgery for primary therapy of the tumour (2 ovaries and one endometrium), while the remaining 2 corresponded to metastasis from a lung primary diagnosed 1 year before and a colonic primary diagnosed 6 years before. The patients with splenic metastasis died on the short term with progression of the disease despite resection of the splenic lesions, while the patients with pancreatic metastasis have survived longer.

Review of histopathological and molecular prognostic features in colorectal cancer

Prediction of prognosis in colorectal cancer is vital for the choice of therapeutic options. Histopathological factors remain paramount in this respect. Factors such as tumor size, histological type and subtype, presence of signet ring morphology and the degree of differentiation as well as the presence of lymphovascular invasion and lymph node involvement are well known factors that influence outcome. Our understanding of these factors has improved in the past few years with factors such as tumor budding, lymphocytic infiltration being recognized as important. Likewise the prognostic significance of resection margins, particularly circumferential margins has been appreciated in the last two decades. A number of molecular and genetic markers such as KRAS, BRAF and microsatellite instability are also important and correlate with histological features in some patients. This review summarizes our current understanding of the main histopathological factors that affect prognosis of colorectal cancer.

[Gastric neuroendocrine tumors. Endoscopic and surgical treatment]

Neuroendocrine tumors (NETs) of the stomach are the most frequent among all neuroendocrine neoplasms in the digestive tract. The diagnosis and classification are complicated by the fact that these tumors have to be categorized not only by common staging and grading but also according to their pathophysiological background (types). The types differ in their biological behaviour (aggressiveness) which influences therapeutic concepts. This article explains and summarizes the etiology and classification of gastric NETs and offers a precise concept for diagnosis and treatment to improve clinical outcome.

[Surgical infections as patient safety problems]

Surgical infections are severe complications of surgical interventions and one of the most important patient safety issues. These are associated with increased morbidity, mortality, costs and decreased quality of life. Prevention of infections is essential, while one has to consider pre-, intra- and postoperative factors and procedures in the clinical practice. In this article we summarize the latest recommendations for clinicians based on the relevant published literature.

Nonalcoholic steatohepatitis (NASH) after pancreaticoduodenectomy: association of pancreatic exocrine deficiency and infection

Previous clinical study has demonstrated that 30-40% of patients undergoing pancreaticoduodenectomy (PD) developed hepatic steatosis. However, nonalcoholic steatohepatitis (NASH) is a little-known complication after PD. Recently we encountered two patients with PD who later developed NASH diagnosed by liver biopsy. Case 1 was a 79-year-old woman who underwent PD for intraductal papillary mucinous neoplasm (IPMN). She had postoperative severe diarrhea due to pseudomembranous enterocolitis. Severe liver dysfunction was observed on the 31st postoperative day. Abdominal computed tomography (CT) on the 32nd day showed remarkably decreased hepatic CT value of 6 HU. Immediate liver biopsy revealed NASH (Brunt criteria: grade 2, stage 2). Case 2 was a 71-year-old woman who underwent PD for IPMN. Liver biopsy on 70th postoperative day, which was performed for assessment of moderate liver dysfunction and decreased hepatic CT value of 44 HU, demonstrated simple steatosis. In the 21st postoperative month, she developed severe urinary tract infection together with marked liver dysfunction. Immediate liver biopsy revealed NASH (Brunt criteria: grade 1, stage 1). For each patient, treatment of infection and high-dose pancreatic enzyme supplements improved liver dysfunction and liver steatosis. Clinical features of our cases seem to support the current leading hypothesis of the pathogenesis of NASH, i.e., the two-hit theory.

Role of living donor liver transplantation in the treatment of hepatitis C virus infection

Hepatitis C virus (HCV) infection is one of the most common indications for liver transplantation worldwide. Because of the existing organ shortage, adult-to-adult living donor liver transplantation (LDLT) has become an important method of expanding the donor pool to meet the ever-increasing need. However, despite advantages such as the quality of the hepatic graft and the timing of the transplant, the exact role of LDLT in the treatment of HCV is still unclear. In this review, we aim to address some of these issues in an effort to highlight both the advantages and disadvantages, as well as to identify the main challenges, of using LDLT for treating patients with HCV infection.

Review of screening for pancreatic cancer in high risk individuals

Pancreatic cancer is difficult to diagnose at an early stage and is associated with a very poor survival. Ten percent of pancreatic cancers result from genetic susceptibility and/or familial aggregation. Individuals from families with multiple affected first-degree relatives and those with a known cancer-causing genetic mutation have been shown to be at much higher risk of developing pancreatic cancer. Recent efforts have focused on detecting disease at an earlier stage to improve survival in these high-risk groups. This article reviews high-risk groups, screening methods, and current screening programs and their results.

A natural orifice transrectal approach for oncologic resection of the rectosigmoid: an experimental study and comparison with conventional laparoscopy

BACKGROUND

A transrectal (TR) approach for natural orifice translumenal endoscopic surgery (NOTES) makes sense for colorectal surgery because the colotomy can be incorporated into subsequent anastomosis. Because cancer is a primary indication for left-sided colon resection, oncologic standards will have to be met by a NOTES procedure. This study aimed to assess whether pure TR rectosigmoidectomy can be performed with strict adherence to oncologic principles compared with a conventional laparoscopically assisted approach (LAP).

METHODS

Human male cadavers were allocated to either TR (n = 4) or LAP (n = 2). A simulated sigmoid lesion was created at 25 cm. Transrectal retrograde mobilization of the rectosigmoid was performed using conventional transanal endoscopic microsurgery (TEM) instrumentation. After ligation of the superior hemorrhoidal artery and further mobilization, the specimen was delivered transanally and divided extracorporeally. Using a circular stapler, NOTES colorectal anastomosis was performed. Lymph node yield, adequate resection margins, and operative time were compared with LAP.

RESULTS

Transrectal retrograde rectosigmoid dissection was achieved in all attempts (4/4) and showed numbers of lymph nodes (median, 5; range, 3-6) similar to the LAP group (median, 4.5; range, 2-7). One pure TR approach failed to resect the lesion. Three TR procedures required additional mobilization via an abdominal approach to provide adequate margins. The mean length of TR specimens was 16 ± 4 cm compared with 31 ± 9 cm achieved by LAP (p < 0.01). The TR operative time was significantly longer (247 ± 15 vs 110 ± 14 min).

CONCLUSION

Lymph node yield during TR rectosigmoidectomy was similar to that achieved by the LAP approach. However, conventional TEM instrumentation alone did not permit adequate colon mobilization. This indicates a need for flexible instrumentation or other technical solutions to perform true NOTES colectomies.

Melanoma stem cells: not rare, but well done

Since the identification of self-renewing cells in the hematopoietic system, stem cells have transformed the study of medicine. Cancer biologists have identified stem-like cells in multiple malignancies, including those of solid organs. This has led to the development of a stem cell theory of cancer, which purports that a subpopulation of self-renewing tumor cells is responsible for tumorigenesis. This contrasts with the stochastic model of tumor development, which advances that all tumor cells are capable of tumor formation. Within the field of melanoma, the identity and existence of cancer stem cells has been the subject of recent debate. Much of the controversy may be traced to differences in interpretations and definitions related to the cancer stem cell theory, and the use of dissimilar methodologies to study melanoma cells. Accumulating evidence suggests that cancer stem cells may exist in melanoma, although their frequency may vary and they may be capable of phenotypic plasticity. Importantly, these primitive melanoma cells are not only capable of self-renewal and differentiation plasticity, but also may confer virulence via immune evasion and multidrug resistance, and potentially via vasculogenic mimicry and transition to migratory and metastasizing derivatives. Therapeutic targeting of melanoma stem cells and the pathways that endow them with virulence hold promise for the design of more effective strategies for amelioration and eradication of this most lethal form of skin cancer.

Impact on Prognosis of Lymph Node Micrometastasis and Isolated Tumor Cells in Stage II Colorectal Cancer

Purpose

Even though the importance of micrometastases (MMS) and isolated tumor cells (ITC) has been brought up by many physicians, its impact on the prognosis in stage II colorectal cancer is uncertain. In this research, we tried to investigate the clinical features of MMS and ITC and to prove any correlation with prognosis.

Methods

The research pool was 124 colorectal cancer patients who underwent a curative resection from April 2005 to November 2009. A total of 2,379 lymph nodes (LNs) were examined, and all retrieved LNs were evaluated by immunohistochemical staining with anti-cytokeratin antibody panel. Clinicopathologic parameters and survival rates were compared based on the presence of MMS or ITC and on the micrometastatic lymph node ratio (mmLNR), which is defined as the number of micrometastatic LNs divided by the number of retrieved LNs.

Results

Out of 124 patients (26.6%) 33 were found to have MMS or ITC. There were no significant differences in clinicopathologic features, such as gender, tumor location and size, depth of invasion, histologic grade, except for age (P = 0.04). The three-year disease-free survival rate for the MMS or ITC positive group was 85.7%, and that for MMS and ITC negative group was 92.8% (P = 0.209). The three-year disease-free survival rate for the mmLNR > 0.25 group was 73.3%, and that for the mmLNR ≤ 0.25 group was 92.9% (P = 0.03).

Conclusion

The presence of MMS or ITC was not closely correlated to the prognosis. However, mmLNR is thought to be a valuable marker of prognosis in cases of stage II colorectal cancer.

Role of focal adhesion kinase in the pathogenesis of colorectal carcinoma

Focal adhesion kinase (FAK) was initially identified as a nonreceptor protein tyrosine kinase localized to the focal contact protein clusters. This enzyme has been shown to facilitate generation of integrin-stimulated signals to downstream targets. It has been reported that activation of FAK leads to a number of processes, including cell attachment, migration, proliferation, and survival. The expression of FAK in colon carcinoma is significantly higher than that in matched cancer-adjacent normal tissue, suggesting that FAK may be an important target for the therapy of colon carcinoma. The inhibition of FAK activation can interrupt many signal pathways involved in colon carcinogenesis and may represent a new therapy strategy for colon carcinoma.

[The transvaginal approach in acute appendicitis]

INTRODUCTION

The purpose of this work is to present 8 minilaparoscopic-assisted transvaginal appendectomies using rigid instruments in patients with acute appendicitis.

MATERIAL AND METHODS

Eight minilaparoscopic-assisted transvaginal appendectomies were performed from the 10th of August 2009 to the 30th of June 2010. The inclusion criteria were women between 18 and 65 years of age with a diagnosis of acute appendicitis. The exclusion criteria were palpable masses, appendicular abscesses, ASA III and IV; morbid obesity (BMI > 35); gynaecological infections; virgin patients and pregnant women. The surgical intervention was performed with rigid instruments. Surgical time, the need for post-operative analgesics, and post-surgical complications.

RESULTS

The age range varied between 18 and 42 years, with a mean of 29.6 years. The mean surgical time was 48.3 minutes (37-75). Analgesics were given to 2 patients after surgery (1 parenteral and 1 oral). Five patients were discharged before 24 hours and 3 at 48 hours. There were no post-operative complications.

CONCLUSIONS

Minilaparoscopic-assisted transvaginal appendectomy with rigid instruments, in selected women is a feasible and safe method, and with better aesthetic results than laparoscopic appendectomy, but future studies will be required that can demonstrate its advantages.

Per-oral cholangioscopy

Direct endoscopic views of bile duct have been described in literature since the 1970s. Since then rapid strides have been made with the advent of technologically advanced systems with better image quality and maneuverability. The single operator semi-disposable per-oral cholangioscope and other novel methods such as the cholangioscopy access balloon are likely to revolutionize this field. Even though cholangioscopy is currently used primarily for characterization of indeterminate strictures and management of large bile duct stones, the diagnostic and therapeutic indications are likely to expand in future. The following is an overview of the currently available per-oral cholangioscopy equipments, indications for use and future directions.

[Medium term results on introducing colorrectal laparoscopic surgery into clinical practice after having an intensive training course]

INTRODUCTION

Endoscopic surgery has characteristics that increase the difficulties of learning. Five years ago, an intensive colorectal laparoscopic surgery course was designed to offer training in the technical bases of this type of surgery. The aim of this article is to determine the impact of the colorectal surgery course on clinical practice, and to investigate the factors that limit its applicability and the training preferences of the surgeons.

MATERIAL AND METHODS

Twenty-two courses of four days duration, with 36 hours of lessons (4 in seminar form and 32 in the surgery), and with 7 trainees, were held between June 2005 and December 2010. A survey was sent out in December 2010 to assess the impact of the course on the colorectal laparoscopic surgery activity of the trainee, to find out the difficulties encountered in its application, and to evaluate the training expectations in endoscopic surgery in this group of surgeons.

RESULTS

The questionnaire was sent to 148 surgeons, with 74 (50%) responses received. The mean period after the course was 26.5 (2-60) months. A monthly increase of more than 5 cases was observed in 70% of the centres. The course enabled them to consolidate the activity in local hospitals, while in university and general hospitals it served to re-launch an initial experience. Among the obstacles that made it difficult to introduce were care load and the availability of a surgeon, particularly in general and university hospitals (P=.001), and in local hospitals it was the availability of patients. The majority of surgeons (70%) believed that specific training was required, preferring a short period in a hospital with experience.

CONCLUSIONS

An intensive course on colorectal laparoscopic surgery enabled the activity to be consolidated or increased in this area. Training in colorectal laparoscopic surgery requires additional teaching efforts, which are currently unstructured.

Câncer de vesícula biliar: experiência de 10 anos em um hospital de referência da Amazônia

OBJETIVO: Analisar os aspectos epidemiológicos-cirúrgicos dos pacientes com câncer de vesícula biliar (CAVB) atendidos em um Hospital Universitário de Belém/PA, no período de 1999-2009. MÉTODOS: estudo observacional, retrospectivo, descritivo-analítico de fonte secundária dos pacientes com diagnóstico de CAVB, no período de 1999-2009. Foram analisados 75 prontuários, sendo 34 pacientes estudados. As informações coletadas foram utilizadas para o estadiamento tumoral TNM do CAVB e para a caracterização clínico-cirúrgica da população estudada. RESULTADOS: 79% eram do sexo feminino, com média de idade de 66,2±11 anos e tempo de sintomatologia de 10,8±17,2 meses, não obtendo relação estatística com o estadio da doença. Dor no hipocôndrio direito, náuseas e icterícia predominaram como sinais/sintomas. A litíase biliar esteve presente em 91% dos casos, sendo positiva em 100% dos pacientes com estadios I/II. A sensibilidade ultrassonográfica para sugestionar o CAVB no pré-operatório foi 14,28%. A operação mais executada foi a colecistectomia simples, tendo como achado intra-operatório predominante, invasão hepática. O adenocarcinoma foi o tipo histológico preponderante, com destaque para os estadios III e IV. CONCLUSÃO: A série estudada apresentou alta incidência de litíase biliar, o adenocarcinoma com estadio avançado foi o mais prevalente. acarretando um pequeno índice de operações com intenção curativa, 30% dos pacientes operados, e uma taxa de mortalidade de 21%. A valorização dos sintomas e a investigação precoce por exames de imagem poderiam favorecer o tratamento, em fases iniciais do CAVB, proporcionando um melhor prognóstico para os pacientes operados.

Modern management of pyogenic hepatic abscess: a case series and review of the literature

Background

Pyogenic hepatic abscesses are relatively rare, though untreated are uniformly fatal. A recent paradigm shift in the management of liver abscesses, facilitated by advances in diagnostic and interventional radiology, has decreased mortality rates. The aim of this study was to review our experience in managing pyogenic liver abscess, review the literature in this field, and propose guidelines to aid in the current management of this complex disease.

Methods

Demographic and clinical details of all patients admitted to a single institution with liver abscess over a 5 year period were reviewed. Clinical presentation, aetiology, diagnostic work-up, treatment, morbidity and mortality data were collated.

Results

Over a 5 year period 11 patients presented to a single institution with pyogenic hepatic abscess (55% males, mean age 60.3 years). Common clinical features at presentation were non-specific constitutional symptoms and signs. Aetiology was predominantly gallstones (45%) or diverticular disease (27%). In addition to empiric antimicrobial therapy, all patients underwent radiologically guided percutaneous drainage of the liver abscess at diagnosis and only 2 patients required surgical intervention, including one 16-year old female who underwent hemi-hepatectomy for a complex and rare Actinomycotic abscess. There were no mortalities after minimum follow-up of one year.

Conclusions

Pyogenic liver abscesses are uncommon, and mortality has decreased over the last two decades. Antimicrobial therapy and radiological intervention form the mainstay of modern treatment. Surgical intervention should be considered for patients with large, complex, septated or multiple abscesses, underlying disease or in whom percutaneous drainage has failed.

Surgical site infections--economic consequences for the health care system

PURPOSES

Unfortunately, surgical site infections (SSIs) are a quite common complication and represent one of the major causes of postoperative morbidity and mortality, and may furthermore lead to enormous additional costs for hospitals and health care systems.

METHODS

In order to determine the estimated costs due to SSIs, a MEDLINE search was performed to identify articles that provide data on economic aspects of SSIs and compared to findings from a matched case-control study on costs of SSIs after coronary bypass grafting (CABG) in a German tertiary care university hospital.

RESULTS

A total of 14 studies on costs were found. The additional costs of SSI vary between $3,859 (mean) and $40,559 (median). Median costs of a single CABG case in the recently published study were $49,449 (€36,261) vs. $18,218 (€13,356) in controls lacking infection (p < 0.0001). The median reimbursement from health care insurance companies was $36,962 (€27,107) leading to a financial loss of $12,482 (€9,154) each.

CONCLUSION

Costs of SSIs may almost triple the individual overall health care costs and those additional charges may not be sufficiently covered. Appropriate measures to reduce SSI rates must be taken to improve the patient's safety. This should also diminish costs for health care systems which benefits the entire community.

Multiple giant diverticula of the jejunum causing intestinal obstruction: report of a case and review of the literature

Multiple diverticulosis of jejunum represents an uncommon pathology of the small bowel. The disease is usually asymptomatic and must be taken into consideration in cases of unexplained malabsorption, anemia, chronic abdominal pain or discomfort. Related complications such as diverticulitis, perforation, bleeding or intestinal obstruction appear in 10-30% of the patients increasing morbidity and mortality rates. We herein report a case of a 55 year-old man presented at the emergency department with acute abdominal pain, vomiting and fever. Preoperative radiological examination followed by laparotomy revealed multiple giant jejunal diverticula causing intestinal obstruction. We also review the literature for this uncommon disease.

Improved preclinical safety assessment using micro-BAL devices: the potential impact on human discovery and drug attrition

Hepatotoxicity is often unpredictable in the early phase of drug discovery and leads to drug attrition in preclinical and clinical development. Here, we discuss the conventional preclinical liver models that do not mimic in vivo livers. We focus on key components such as new sources of hepatocyte-derived human stem cells, enhanced direct oxygenation, defined biocompatibility nanoscaffolds, organotypical cellular models, dynamic culture, and metabolite status inside and outside the cell for effective configuration for the development of a bioartificial liver (BAL) device to mimic the in vivo liver microenvironment. The potential for development of BAL devices could open up new avenues in: (i) hepatotoxicity assessment for selecting drug candidates during preclinical screening; and (ii) therapeutic approaches for liver cell therapy at the clinical stage.

Radiofrequency ablation versus resection for liver tumours: an evidence-based approach to retrospective comparative studies

BACKGROUND

Recently randomized controlled trials have been advocated to compare radiofrequency ablation (RFA) and hepatic resection (HR) in resectable tumours and determine whether differences in observed survivals result from the heterogeneity in previous studies between RFA (treating unresectable lesions) and HR (treating lesions deemed resectable). We reviewed the literature that directly compares the treatments and employed an evidence-based approach to examine the data.

MATERIALS AND METHODS

All studies comparing RFA and HR were included. Primary outcomes were the overall survival (OS) and disease-free survival (DFS) at 3 and 5 years. A subgroup analysis was conducted for solitary or small tumors (<4 cm for colorectal metastases (CRM) or <5 cm for hepatocellular carcinoma (HCC)).

RESULTS

Most studies were retrospective. For CRM, HR was markedly superior to RFA in respect of 3- and 5-year OS as well as 5-year DFS including tumours smaller than 4 cm and solitary lesions. For HCC, HR was markedly superior to RFA for 3- and 5-year OS as well as 3-year DFS, and produced a better OS at 3 years for solitary lesions and DFS at 3 years for small tumours.

CONCLUSIONS

Multiple factors determine outcomes following treatment of liver tumours. Small or solitary lesions seem the most appropriate ones to study as this reduces the number of confounding variables, but even in these cases HR confers a better OS and DFS than RFA for both CRM and HCC. If our data are confirmed it will be important to examine other factors influencing the response.

Peroral cholangioscopy in the new millennium

Peroral cholangioscopy was first described in 1970s and has recently gained popularity. Peroral cholangioscopy is appealing to therapeutic endoscopists because a direct intraluminal view of the biliary duct system offers possibilities for diagnosis and interventions beyond that which other imaging or endoscopic modalities can provide. As the image quality of cholangioscopies improves, so too does their diagnostic capability, and as their durability and maneuverability increases, so too does their potential use for therapeutic applications. This editorial is intended to provide a brief review of recent developments in peroral cholangioscopy and current indications for its use.

Cell-based therapeutics for liver disorders

INTRODUCTION

Due to a lack of adequate liver donors and post-surgical complications, researchers propose that cell therapy should be an alternative treatment for patients with end-stage liver diseases.

DATA SOURCES

We performed a literature review on cell-based therapy for liver disorders.

AREAS OF AGREEMENT

Due to growing numbers of patients on waiting lists for liver transplantation, a substitute treatment strategy is needed for our patients. Cell therapy can save patients who are in life-threatening situations, enabling them to have more time and increase their chances of survival. Pluripotent stem cells can be a good resource for cell-based therapy after the establishment of efficient differentiation protocols in addition to the settlement of ethical and immunological issues. Cell-based therapy will be applicable after the approval of its efficiency via animal model studies.

AREAS OF CONTROVERSY

Transplanted cells cannot integrate into the recipient liver and lose their functionality after a limited time. The rate of homing and transdifferentiation of transplanted cells into hepatocytes is scant.

GROWING POINTS

Application of autologous bone marrow mononuclear cells (MNCs), hematopoietic and mesenchymal stem cells (HSCs and MSCs) has improved the general conditions of certain patients. Although this improvement is temporary, new studies have focused on increasing their performance. TIMELY AREAS FOR DEVELOPING RESEARCH: The safety, feasibility and efficacy of applying MNCs, HSCs and MSCs in liver disorders have been proven in clinical trials. Patient-specific cell therapy after the production of induced pluripotent stem cells and new discoveries in somatic cell conversion during transdifferentiation are promising insights.

Intraductal papillary mucinous neoplasm: Coming of age

Intraductal papillary mucinous neoplasm (IPMN) is a disease in evolution. Since its first description almost 30 years ago, a better understanding of the disease has steadily accrued. Yet, there are numerous challenges still for clinicians who treat this fascinating disease. A group of leading content experts on IPMN was assembled and charged with presenting cutting-edge knowledge on various topics for which they have considerable experience. This manuscript provides an historical perspective of both clinical and biological quandaries that have been resolved to date. Furthermore, it poses new avenues for investigation while highlighting the contributions of the various authors to this collective review.

Safety and application of laparoscopic gastrectomy for benign gastric disease and gastric cancer

INTRODUCTION

Laparoscopic gastrectomy is rapidly expanding despite reservations by some surgeons regarding its safety and radicality. The aim of this study was to evaluate patients undergoing laparoscopic gastrectomy for both benign and malignant disease with particular emphasis on technical feasibility, safety, effectiveness and complications.

PATIENTS AND METHODS

Review of prospectively collected data of patients who underwent laparoscopic gastrectomy from May 2005 to September 2009 under the care of one consultant surgeon.

RESULTS

A total of 61 laparoscopic gastrectomies were performed (35 men and 26 women) with a median age of 68 years (range, 41-90 years). There were 39 distal gastrectomies (19 adenocarcinoma, 6 gastrointestinal stromal tumour [GIST], 4 benign gastric outlet obstruction, 4 high-grade dysplasia in gastric adenomas, 4 non-healing ulcers, 2 gastric antral vascular ectasia [GAVE]); 15 sub-total gastrectomies (13 adenocarcinomas, 2 GIST); and 7 total gastrectomies (5 adenocarcinomas, 1 GIST, 1 carcinoid). Median follow-up was for 48 months (range, 1-72 months). There was one death, two major and six minor complications. All patients with complications made a satisfactory recovery.

CONCLUSIONS

Laparoscopic gastrectomy is associated with a low mortality (1.75%) and major morbidity (3.50%). Although technically demanding, especially when a D2 lymphadenectomy is performed, our results have shown that tailored laparoscopic resection based on tumour characteristics with either D1 or D2 lymphadenectomy results in good surgical and oncological outcomes.

NOTES-Natural orifice transluminal endoscopic surgery: Why not?

Since natural orifice transluminal endoscopic surgery (NOTES) was first described by Anthony Kalloo, it has attracted tremendous interest from surgeons and gastroenterologist all around the world. This special issue of the World Journal of Gastrointestinal Surgery explores the current possibilities and future potential of the most disruptive revolution in the field of surgery represented by the NOTES approach. In the future, new technologies developed for this approach and deeper insight into several gastrointestinal diseases will lead to the design of completely new interventional procedures and change the way we will operate, bringing us to the previously unimaginable goal of “no scar surgery”.

Clinical management of cystic echinococcosis: state of the art, problems, and perspectives

Clinical management of cystic echinococcosis (CE) has evolved over decades without adequate evaluation of important features such as efficacy, effectiveness, rate of adverse reactions, relapse rate, and cost. CE occurs in health care environments as different as Europe/North America and resource-poor countries of the South and the East. This creates setting-specific problems in the management of patients. Furthermore, studies carried out in either of the two fundamentally different environments lack external validity, i.e., results obtained in one setting may be different from those in the other and practices that can work in one may not be applicable to the other. In this paper, we review the current management procedures of CE with particular emphasis on the evidence base and setting-specific problems.