Small bowel cancer in the United States: changes in epidemiology, treatment, and survival over the last 20 years. Ann Surg. 2009;249:63-71. [PMID: 19106677 DOI: 10.1097/sla.0b013e31818e4641]

Clinical Efficacy of Various Diagnostic Tests for Small Bowel Tumors and Clinical Features of Tumors Missed by Capsule Endoscopy

Background. We aimed to evaluate the efficacy of various diagnostic tools such as computerized tomography (CT), small bowel follow-through (SBFT), and capsule endoscopy (CE) in diagnosing small bowel tumors (SBTs). Additionally, we aimed to evaluate the clinical features of SBTs missed by CE. Methods. We retrospectively studied 79 patients with histologically proven SBT. Clinical data were analyzed with particular attention to the efficacy of CT, SBFT, and CE in detecting SBT preoperatively. We also analyzed the clinical features of SBTs missed by CE. Results. The most common symptoms of SBT were bleeding (43%) and abdominal pain (13.9%). Diagnostic yields were as follows: CT detected 55.8% of proven SBTs; SBFT, 46.1%; and CE, 83.3%. The sensitivity for detecting SBTs was 40.4% for CT, 43.9% for SBFT, and 79.6% for CE. Two patients with nondiagnostic but suspicious findings on CE and seven patients with negative findings on CE were eventually found to have SBT. These nine patients were eventually diagnosed with gastrointestinal stromal tumor (4), small polyps (3), inflammatory fibroid polyp (1), and adenocarcinoma (1). These tumors were located in the proximal jejunum (5), middle jejunum (1), distal jejunum (1), and proximal ileum (1). Conclusion. CE is more efficacious than CT or SBFT for detecting SBTs. However, significant tumors may go undetected with CE, particularly when located in the proximal jejunum.

Jejunal Intussusception: A Rare Presentation of Carcinoid Tumor

A 55-year-old male presented to the emergency department with sudden onset of diffuse abdominal pain for one day. Physical examination was remarkable for tenderness in the umbilical region. A CT scan of the abdomen showed intussusception involving the jejunum without any mass. The patient then underwent an exploratory laparotomy. During surgery, the distal jejunum was intussuscepted with mesenteric lymphadenopathy. Liver showed nodular deposits in both lobes of the liver. The involved small bowel segment was resected with primary anastomosis and liver was biopsied. Pathological examination showed multifocal deposits of well-differentiated carcinoids in the jejunum. The liver and mesenteric deposits were positive for metastatic carcinoid. Patient recovered well without any complications.

Role of double-balloon enteroscopy in malignant small bowel tumors

AIM

To assess the double-balloon enteroscopy (DBE) role in malignant small bowel tumors (MSBT).

METHODS

This is a retrospective descriptive study performed in a single center. All consecutive patients who underwent a DBE with final diagnosis of a malignant neoplasm from 2004 to 2014 in our referral center were included. Patient demographic and clinical pathological characteristics were recorded and reviewed. MSBT diagnosis was achieved either by DBE directed biopsy with multiple tissue sampling, endoscopic findings or histological analysis of surgical specimen. We have analyzed double-balloon enteroscopy impact in outcome and clinical course of these patients.

RESULTS

Of 627 patients, 28 (4.5%) (mean age = 60 ± 17.3 years) underwent 30 procedures (25 anterograde, 5 retrograde) and were diagnosed of a malignant tumor. Patients presented with obscure gastrointestinal bleeding (n = 19, 67.9%), occlusion syndrome (n = 7, 25%) and diarrhea (n = 1, 3.6%). They were diagnosed by DBE biopsy (n = 18, 64.3%), histological analysis of surgical specimen (n = 7, 25%) and unequivocal endoscopic findings (n = 2, 7.1%). Gastrointestinal stromal tumor (n = 8, 28.6%), adenocarcinoma (n = 7, 25%), lymphoma (n = 4, 14.3%), neuroendocrine tumor (n = 4, 14.3%), metastatic (n = 3, 10.7%) and Kaposi sarcoma (n = 1, 3.6%) were identified. DBE modified outcome in 7 cases (25%), delaying or avoiding emergency surgery (n = 3), modifying surgery approach (n = 2) and indicating emergency SB partial resection instead of elective approach (n = 2).

CONCLUSION

DBE may be critical in the management of MSBT providing additional information that may be decisive in the clinical course of these patients.

Lifestyle factors and small intestine adenocarcinoma risk: A systematic review and meta-analysis

BACKGROUND

Although the incidence of small intestinal adenocarcinoma (SIA) is low, rates are increasing and little information regarding modifiable lifestyle risk factors is available.

AIM

To provide a systematic review of lifestyle factors and SIA risk.

METHODS

Ovid MEDLINE, EMBASE and Web of science were searched from inception to week 1 October 2013. Nine publications that reported on SIA risk in relation to alcohol intake (n=6), tobacco smoking (n=6), diet (n=5), body mass (n=3), physical activity (n=1), hormone use (n=1) and/or socio-economic status (n=3) were retrieved. Results for alcohol, smoking and SIA risk were pooled using random-effects meta-analyses to produce relative risks (RR) and 95% confidence intervals (CI).

RESULTS

The summary RR for individuals consuming the highest versus lowest category of alcohol intake was 1.51 (95% CI 0.83-2.75; n=5 studies) with significant increased risks emerging in sensitivity analysis with reduced heterogeneity (RR: 1.82, 95% CI: 1.05-3.15; n=4 studies). The pooled SIA RR for individuals in the highest versus lowest category of smoking was 1.24 (95% CI 0.71-2.17; n=5 studies). In relation to dietary factors, high fibre intakes and normal body weight may be protective, while high intakes of red/processed meat and sugary drinks may increase SIA risk. Evidence on socio-economic status and SIA risk was equivocal. Data on other factors were too sparse to draw any conclusions.

CONCLUSIONS

Alcohol may be associated with an increased risk of SIA. Further investigation of lifestyle factors, particularly alcohol, smoking and diet, in the aetiology of this cancer is warranted in large consortial studies.

Clinical trial designs for rare diseases: studies developed and discussed by the International Rare Cancers Initiative

BACKGROUND

The past three decades have seen rapid improvements in the diagnosis and treatment of most cancers and the most important contributor has been research. Progress in rare cancers has been slower, not least because of the challenges of undertaking research.

SETTINGS

The International Rare Cancers Initiative (IRCI) is a partnership which aims to stimulate and facilitate the development of international clinical trials for patients with rare cancers. It is focused on interventional--usually randomized--clinical trials with the clear goal of improving outcomes for patients. The key challenges are organisational and methodological. A multi-disciplinary workshop to review the methods used in ICRI portfolio trials was held in Amsterdam in September 2013. Other as-yet unrealised methods were also discussed.

RESULTS

The IRCI trials are each presented to exemplify possible approaches to designing credible trials in rare cancers. Researchers may consider these for use in future trials and understand the choices made for each design.

INTERPRETATION

Trials can be designed using a wide array of possibilities. There is no 'one size fits all' solution. In order to make progress in the rare diseases, decisions to change practice will have to be based on less direct evidence from clinical trials than in more common diseases.

Prognostic factors and treatment outcomes in patients with Small Bowel Adenocarcinoma (SBA): the Royal Marsden Hospital (RMH) experience

Background

SBA is a rare tumour which carries a poor prognosis. Very few data on prognostic factors and treatment outcomes are available. We conducted a retrospective analysis of patients treated for SBA at our institution.

Methods

Clinico-pathological characteristics, treatments and outcomes of all the SBA patients treated consecutively from 1996 to 2011 were retrospectively collected. The prognostic value of baseline factors was assessed using the Cox regression model. The Kaplan-Meier method was used to estimate the survival outcomes.

Results

Eighty-four patients with SBA were treated during the study period. Of these, 48 presented with early stage SBA, while 36 had unresectable disease. All early stage SBA patients (58.3% males; median age, 59 years) underwent resection (R0 in 44/48) and 27 (56%) received adjuvant chemotherapy. Median relapse-free survival and overall survival (OS) were 31.1 months (95% CI: 8.0-54.3) and 42.9 (95% CI: 0–94.9), respectively. In univariate analyses, poor histological differentiation (p = 0.025) and lymphovascular invasion (p = 0.003) were prognostic for OS. In the group of patients with relapsed, unresectable or metastatic disease (n = 59), systemic chemotherapy was administered in 46 cases (78%). The response rate to first line chemotherapy was 50%. Median progression-free survival and OS were 8.8 (95% CI: 5.5-12.3) and 12.8 months (95% CI: 8.4-17.2), respectively. In univariate analyses, low albumin (p = 0.041) and high platelet count (p = 0.007) were prognostic for OS.

Conclusion

Prospective clinical trials are needed to inform the management of SBA patients. Prognostic factors evaluated in our series may be useful for patient stratification and treatment selection in future studies.

Post-surgical surveillance of locally advanced ileal carcinoids found by routine ileal intubation during screening colonoscopy: a case series

INTRODUCTION

Carcinoid tumors are the most common type of small bowel tumor, and the incidence is rising. The majority of small bowel carcinoid tumors arise within 60 cm of the ileocecal valve. The addition of ileoscopy to screening colonoscopy can detect asymptomatic small bowel carcinoid tumors and improve long-term prognosis through early surgical resection. Ileoscopy is a brief procedure with a high success rate and minimal complications beyond those of colonoscopy. The use of ileoscopy during screening colonoscopy has led to an increase in the early-stage detection of locoregional small bowel carcinoid tumors that can be completely treated with surgery alone, and as such has improved long-term prognosis in these patients.

CASE PRESENTATIONS

Five asymptomatic Caucasian patients, 3 males and 2 females, from 53 to 70 years old (mean age, 60 years old), were diagnosed with locoregional ileal carcinoids during routine colonoscopy with ileoscopy. Since having an ileocolectomy and without adjuvant treatment, no patient has developed tumor recurrence over a follow-up period of one and half to 12 and a half years.

CONCLUSION

The early detection of carcinoid tumors by ileoscopy during screening colonoscopy can lead to increased long-term survival in patients with locally invasive disease. The high success rate and brief duration of the procedure, in addition to the lack of associated morbidity and mortality suggest that with further studies, routine ileoscopy during colonoscopy may be promising in the diagnosis of small bowel carcinoid tumors.

Leiomyosarcoma of the small bowel: Report of a case and review of the literature

INTRODUCTION

Leiomyosarcoma of the small bowel is an extremely rare form of gastrointestinal malignancy. Small bowel tumours are usually asymptomatic at the early stages, and difficult to visualise by upper and lower endoscopy.

PRESENTATION OF CASE

An 83-year-old gentleman presented in surgical outpatient clinic with chronic anaemia, abdominal discomfort and a single episode of malaena. Initial OGD and colonoscopy were both unremarkable. Subsequent CT revealed a mass in the right iliac fossa of likely small bowel origin, leading to an urgent laparotomy and resection with primary anastomosis. Histopathology showed a high grade leiomyosarcoma with no signs of metastasis and confirmatory immunological staining. Post-surgery follow up remains unremarkable.

DISCUSSION

Leiomyosarcomas of the small bowel are extremely rare entities, particularly following the advent of robust immunohistological diagnostic methods allowing differentiation from GISTs. As small bowel tumours are often not visualised by upper and lower endoscopy, further investigations to visualise the small bowel are crucial, generally in the form of magnetic resonance enterography, CT colonography or wireless capsule endoscopy.

CONCLUSION

The treatment of such tumours remains predominantly centred around surgical resection, and prognosis is dependent on tumour size and histological staging.

Characterization of a new small bowel adenocarcinoma cell line and screening of anti-cancer drug against small bowel adenocarcinoma

Small bowel adenocarcinoma (SBA) is a rare, aggressive malignancy with a poor prognosis, and the mechanisms of carcinogenesis in SBA remain unclear. Our aims were to investigate the molecular mechanisms underlying SBA and to identify treatments by establishing and characterizing an SBA cell line and performing anti-cancer drug screening. SIAC1 cells, established from jejunal SBA, showed epithelial characteristics and formed organoids in 3D culture. SIAC1 cells had a heterozygous β-catenin deletion mutation, resulting in a stable β-catenin protein with enhanced Wnt/β-catenin activity. SIAC1 cells lacked MLH1 and MSH6 expression, and target genes such as TGFBR2 and ACVR2 showed frameshift mutations. Among 10 clinical SBA samples, 2 (20%) had interstitial deletions in β-catenin, expression of mismatch repair protein was aberrant in 4 (40%), and heterozygous frameshift mutations of three target genes were found in all 10 samples. On screening assay using 140 compounds, eribulin significantly inhibited SIAC1 cell growth both in vitro and in vivo by inhibition of the Wnt/β-catenin pathway via enhanced degradation of β-catenin. In conclusion, we established an SBA cell line with molecular characteristics similar to those of clinical SBA samples, including β-catenin deletion and mismatch repair protein deficiency, that will be useful for SBA research. Eribulin might be a candidate for SBA treatment due to its inhibitory effect on Wnt/β-catenin signaling.

Primary small-bowel malignancy: update in tumor biology, markers, and management strategies

PURPOSE

Primary small-bowel malignancies (SBM) are rare tumors but their incidence is rising. An estimated 9160 new cases and 1210 deaths due to SBM may occur in the USA in 2014. We review advances made in tumor biology, immunohistochemistry, and discuss treatment strategies for these malignancies.

METHODS

Relevant articles from PubMed/Medline and Embase searches were collected using the phrases "small-bowel adenocarcinoma, gastrointestinal carcinoids, gastrointestinal stromal tumors, small-bowel leiomyosarcoma, and small-bowel lymphoma".

RESULTS

Advances in imaging techniques such as wireless capsule endoscopy, CT and MRI enterography, and endoscopy (balloon enteroscopy) along with discovery of molecular markers such as c-kit and PDGFRA for GIST tumors have improved our ability to diagnose, localize, and treat these patients. Early detection and surgical resection offers the best chance for long-term survival in all tumors except bowel lymphoma where chemotherapy plays the main role. Adjuvant therapy with imatinib has improved overall survival for GIST tumors, somatostatin analogs have improved symptoms and also inhibited tumor growth and stabilized metastatic disease in carcinoid disease, but chemotherapy has not improved survival for adenocarcinoma.

CONCLUSIONS

Recent advances in molecular characterization holds promise in novel targeted therapies. Currently ongoing trials are exploring efficacy of targeted therapies and role of adjuvant therapy for adenocarcinoma and results are awaited. Early detection and aggressive surgical therapy for all localized tumors and lymph node sampling particularly for adenocarcinoma remains the main treatment modality.

Wilkie's Syndrome and Left Adnexal Mass: Unusual Presentation of Duodenal Adenocarcinoma

Duodenal adenocarcinoma (DACa) is a rare malignancy, the presenting symptoms of which are vague and nonspecific. We report the case of a patient presenting with symptoms of subacute small bowel obstruction whose CT scan revealed i) left adnexal mass and ii) compression of 3(rd) portion of duodenum with reduced aortomesentric angle consistent with Wilkie's syndrome (WS). Laparatomy in addition revealed a distal duodenal stricture, which showed a well differentiated DACa causing subtotal intestinal obstruction. The ovarian mass revealed adenocarcinoma with similar morphology. Immunophenotypic analysis revealed positive expression of CK 20 and CDX 2 and absence of CK 7 staining in the tumours consistent with Primary DACa with ovarian metastasis. We further concluded that the WS resulted from reduced mesenteric fat pad caused by DACa induced cachexia. The case highlights the elusive nature of duodenal malignancy and emphasises the importance of meticulous small bowel examination during exploration of ovarian masses.

Regional specialization within the intestinal immune system

The intestine represents the largest compartment of the immune system. It is continually exposed to antigens and immunomodulatory agents from the diet and the commensal microbiota, and it is the port of entry for many clinically important pathogens. Intestinal immune processes are also increasingly implicated in controlling disease development elsewhere in the body. In this Review, we detail the anatomical and physiological distinctions that are observed in the small and large intestines, and we suggest how these may account for the diversity in the immune apparatus that is seen throughout the intestine. We describe how the distribution of innate, adaptive and innate-like immune cells varies in different segments of the intestine and discuss the environmental factors that may influence this. Finally, we consider the implications of regional immune specialization for inflammatory disease in the intestine.

Small bowel neuroendocrine tumors: the benefits of surgical intervention

Well-differentiated SI NETs are on the rise. Due in part to the indolent nature of these tumors, patients typically have a delay in diagnosis and present with metastatic disease. Surgeries for symptoms of either chronic intermittent small bowel obstruction and/or ischemia or from carcinoid syndrome have proven to provide excellent palliation. Most recently, several series have demonstrated an improved survival in those patients in whom the primary, locoregional disease has been resected. Several newer adjuncts have been developed to aid in the hepatic directed therapies such as ablation therapies, embolization and Y spheres. The ability to cytoreduce 70% or more of the hepatic tumor burden has been shown to not only to provide a biochemical and as such a clinical response, but also appears to prolong survival. All patients with SI NETs should be assessed in a multidisciplinary clinic and the first line of therapy should always be to assess surgical resectabilty.

Incidence of gastroenteropancreatic neuroendocrine tumours: a systematic review of the literature

Based on the current medical literature, the worldwide incidence of neuroendocrine tumours (NETs) seems to have increased; however, a systematic literature overview is lacking. This study aimed to collect all available data on the incidence of gastroenteropancreatic (GEP)-NETs and characteristics of population to establish their epidemiology. A sensitive MEDLINE search was carried out. The papers were selected via a cascade process that restricted the initial pool of 7991 articles to 33, using predefined inclusion and exclusion criteria. Original articles evaluating the incidence of sporadic GEP-NETs in regional, institutional and national registries were considered. The majority of data originated from the US National Cancer Institute Surveillance, Epidemiology and End Results database and from national cancer registries in Western Europe. Generally, because of the retrospective nature of existing databases the outcomes of studies might be biased, which hinders the drawing of firm conclusions. The age-adjusted incidence of GEP-NETs has increased steadily over the past four decades (1973-2007), increasing 3.65-fold in the USA and 3.8- to 4.8-fold in the UK. Incidence has changed variably from one anatomical site to another. The greatest increase in incidence occurred for gastric and rectal NETs, while the smallest increase occurred for small intestine NETs. There were gender and racial differences, which differed site by site and, in some cases, changed over time. The incidence rates (IRs) of GEP-NETs have increased significantly in the last 40 years. Data are only available from North America, Western Europe and Japan. A site-by-site analysis revealed that the IRs of some NETs increased more than those of others.

ERBB2 gene as a potential therapeutic target in small bowel adenocarcinoma

AIM OF THE STUDY

Small bowel adenocarcinoma (SBA) is a rare and aggressive tumour with poor outcomes. Because of its low incidence, the number prospective studies remains insufficient leading to poor knowledge and absence of standard of care. Aiming to better understand small bowel carcinogenesis we investigated the frequency of somatic mutations in a large data set of patients in more than 740 mutational hotspots among 46 genes.

METHODS

In total, 83 SBA cases were selected from two European databases. The sequencing was performed using the Ion 316 Chip. Additionally we looked into ERBB2 expression and microsatellite instability (MSI) status.

RESULTS

The tumours most frequently were duodenal (47%) and stage ⩾3 (63%). Eight genes were mutated with a frequency >5%: KRAS, TP53, APC, SMAD4, PIK3CA, ERBB2, BRAF and FBXW7. ERBB2 alterations are present in 10 patients (12%) through mutations (7 cases) or amplifications (3 cases). ERBB2 mutations were significantly associated with duodenal tumour location (P=0.04). In this group, there was a positive association with dMMR status (P=0.006) and APC mutation (P=0.02) but negative association with p53 mutations (P=0.038).

CONCLUSIONS

This study describes the first large screening of somatic mutations in SBA using next generation sequencing. The ERBB2 mutation was revealed to be one of the most frequent alterations in SBA with a distribution dependent on tumour location. In most cases ERBB2 mutation was identical (p.L755S). In clinical practice, this may suggest that more than 10% of the patients with SBA could be treated using an anti-ERBB2-targeted agent.

Evaluation and management of small-bowel tumors in the era of deep enteroscopy

In summary, small-intestine tumors are a rare phenomenon, but they are being discovered more frequently with newer diagnostic techniques. Prior studies of the small bowel were limited, making the diagnosis difficult. With the advent of CE and deep enteroscopy, gastroenterologists are finding these tumors at an earlier stage, thereby offering better management options for these patients. Although the incidence of small-bowel tumors has increased, the survival rates have remained the same. This may be a lag-time bias but could be a future area of research in this emerging field.

Defining the role of adjuvant therapy: ampullary and duodenal adenocarcinoma

Adenocarcinomas of the ampulla of Vater and duodenum are more rare than pancreatic cancer and have a better prognosis. However, studies conducted on the management of these cancers, such as adjuvant chemotherapy and radiation therapy, are limited by small sample sizes and series that are retrospective. This review evaluates ampullary and duodenal adenocarcinomas with regard to incidence, anatomy, prognostic features, patterns of failure, and the available literature studying adjuvant therapy.

Retrospective analysis of 119 small bowel adenocarcinoma in Chinese patients

BACKGROUND

Small bowel adenocarcinoma (SBA) is a rare occurrence and few studies have addressed it adequately, especially in China.

METHODS

Clinicopathological features, survival and prognostic analysis were retrospectively done in SBA patients admitted between 2001 and 2011 in the People's Liberation Army General Hospital.

RESULTS

The study included 68 men and 51 women with a median age of 56.5 year. Tumors mainly occurred in duodenum (93.3%). Abdominal pain was the most frequent symptom (36.8%). Patients (30.3%) who received postoperative adjuvant chemotherapy had an increased, but not significant, median overall survival (MOS) rate compared to those who did not receive chemotherapy (37 vs 35 months, p = .324). One year disease free survival rate was higher in patients receiving postoperative chemotherapy (83.3% vs 71.1%). Patients survived longer in the curative surgery group (median survival time of 49.0 months) than those in the palliative group (7.0 months) (p < .001). Node-negative patients survived longer than node-positive patients (median OS: 49.0 vs 21.0 months, p = .004). Depth (95% CI: 1.013-1.517, p = .037), node involvement (95% CI: 1.234-3.890, p = .007), palliative surgery (95% CI, 2.998-10.555, p = .0005), and the site of tumor (95% CI: 0.052-0.970, p = .045) were independent predictors of OS in a multivariate analysis.

CONCLUSIONS

SBA is rare and there is lack of obvious clinical manifestations. Depth, node involvement, palliative surgery, and the site of tumor are associated with a poor prognosis. Our analysis highlights the need for further studies to find out the exact role of postoperative adjuvant chemotherapy in these patients.

The clinical pathological features, diagnosis, treatment and prognosis of small intestine primary malignant tumors

The aim of the study was to describe and analyze the clinicopathological features and diagnosis of Chinese patients with small intestine primary malignant tumors and to explore the best therapy to small bowel adenocarcinoma (SBA). More than 26,000 patients with digestive tract malignant tumors received treatment in PLA hospital from 2000 to 2011, and among them, there were 887 patients who had small intestine primary malignant tumors, and 666 of 887 patients had the completed basic clinical documents. We retrospectively analyzed the correlation between clinical and pathological features of the 666 patients and analyzed the survival and prognosis of 173 SBA patients with follow-up data. Both the number of patients with primary malignant tumors of the small intestine and the number of patients who received chemotherapy showed an increasing trend. The ratio of male to female was 1.58:1. The male patients significantly exceed the female patients with tumors of non-ampullary duodenum, jejunum and duodenal ampulla; and most of the patients are over 60 years of age. For patients burdened with either of the pathological types of tumors, the males exceeded the females, but there was no significant difference. Abdominal pain was the main clinical manifestation for patients with tumors of non-ampullary duodenum, jejunum and ileum, and the most common clinical manifestations were jaundice and abdominal pain for patients with ampullary duodenal tumors, adenocarcinoma, neuroendocrine tumors and sarcoma. In addition, patients with stromal tumors were prone to gastrointestinal bleeding. Gastrointestinal endoscopy was the most common examinational procedure. Patients under 60 years of age were prone to surgery and chemotherapy after surgery, and patients over 60 years of age were prone to supportive treatment and chemotherapy without surgery. The medium overall survival of patients who received surgery without chemotherapy, chemotherapy after surgery, chemotherapy without surgery and supportive treatment were 40.0, 35.0, 9.0 and 7.5 months, respectively. For the 173 SBA patients with follow-up data, treatment, age and distant metastasis were important prognostic factors; 149 of 173 SBA patients received only surgery, and the depth of tumor invasion, lymph node metastasis and surgical approach were important prognostic factors. Adjuvant chemotherapy had not provided significant benefit to prolong OS in patients with adenocarcinoma. The incidence of small intestine primary malignant tumors is very low, and it is difficult to diagnose. The patients should be aggressively treated and regularly followed up with related clinical and pathological features. Currently, surgery is the most effective treatment, and the role of chemotherapy needs further large-scale clinical studies.

Malignant tumours of the small intestine

Adenocarcinoma, neuroendocrine tumours, sarcomas and lymphomas are the four most common malignant tumours arising in the small intestine, although over forty different histological subtypes are described. Collectively these account for only 2% of cancers of the digestive system. The incidence of small bowel cancer has increased in recent decades with a four-fold increase in carcinoid tumours. Risk factors for small bowel tumours include coeliac disease, inflammatory bowel disease and a number of genetic abnormalities. The non-specific nature of their symptoms and the difficulty in visualising these tumours with normal endoscopic techniques often results in late diagnosis. Furthermore the paucity of literature on this topic has made it difficult to standardise management. There has however been marked improvement in imaging methods resulting in earlier diagnosis in many cases. As expected, early detection of localised, well differentiated tumours followed by surgical resection with negative margins offers the best chance of long term survival. Better adjuvant treatment, notably for gastrointestinal stromal tumours, has improved 5-year survival rates significantly. Development of surveillance guidelines for at risk populations may be a valuable way of improving early diagnosis of this challenging group of conditions.

What are the latest pharmacotherapy options for small bowel adenocarcinoma?

Incidence of small bowel adenocarcinoma is slowly but steadily increasing. As we gain more knowledge of the molecular basis of this disease, we may be able to approach it via using novel biologic or targeted therapies with or without traditional chemotherapy agents. In the meantime, early diagnosis is still best as it prompts early surgical resection and offers potential cure. The role of adjuvant and neoadjuvant therapy is currently being explored in clinical trials. Several clinical trials have suggested that first-line chemotherapy for patients with metastatic disease should consist of either 5-fluorouracil-leucovorin-oxalipatin or capecitabine-oxaliplatin, while 5-fluorouracil-leucovorin-irinotecan can be reserved for second-line treatment. However, we realize the limitations of these studies, given their small sample size and/or retrospective nature. Single-agent 5-fluorouracil/capecitabine should be considered in patients who are either intolerant to or experience significant side effects with oxaliplatin or irinotecan. We believe that cancers originating in the ampulla of Vater probably deserve a prospective randomized trial of cisplatin-gemcitabine, the current standard of therapy for advanced biliary malignancies.

Surgical procedure depending on the depth of tumor invasion in duodenal cancer

BACKGROUND

Duodenal cancer excluding Vater's papilla cancer is a relatively rare disease entity; therefore, the most appropriate operative methods depending on the tumor condition, such as the tumor site and/or depth of invasion, still remain unclear. The aim of this study is to determine an appropriate operative method and an appropriate extent of lymph node dissection depending on tumor site or tumor invasion depth.

METHODS

Data of a total of 35 patients with duodenal cancer who underwent resectional surgery with curative intent were reviewed retrospectively, and the clinicopathological factors and survival outcomes were investigated.

RESULTS

Overall 5-year survival rates of all resected cases were 63.0% (median survival: 9.1 years). Multivariate analysis identified histological G3/4 (P = 0.002) and presence of lymph node metastasis (P = 0.004) as independent adverse prognostic factors. Of the 35 patients, 11 (31.4%) had lymph node metastasis. In all patients with the tumor invasion depth within limited to the mucosa or submucosa (T1a or T1b), lymph node metastasis was absent (0/15 patients). T2/3/4 tumor (P < 0.001) and G3/4 (P = 0.021) were identified as predictors of the presence of lymph node metastasis. Four (11.4%) of the 35 patients had metastasis in the infrapyloric node.

CONCLUSIONS

Limited resection is sufficient for patients with T1a tumor. In the case of T1b tumor, limited resection or pancreatoduodenectomy may be selected after performing pancreaticoduodenal node biopsy as sentinel lymph node biopsy. For patients with T2-4 tumor, pancreatoduodenectomy or substomach preserving pancreatoduodenectomy (excepting Pylorus-preserving pancreatoduodenectomy) with regional lymph node dissection should be performed.

Imaging the small bowel

PURPOSE OF REVIEW

Radiologic investigations continue to play a pivotal role in the diagnosis of pathologic conditions of the small intestine despite enhancement of capsule endoscopy and double-balloon endoscopy. Imaging techniques continue to evolve and new techniques in MRI in particular, are being developed.

RECENT FINDINGS

Continued advances in computed tomography (CT) and MRI techniques have reinforced the importance of these imaging modalities in small bowel assessment. The more invasive enteroclysis technique yields better small bowel distension for both CT and MRI when compared with peroral enterography, but no clinically significant difference is seen in terms of diagnostic accuracy. Recent concern regarding radiation exposure means that MRI is gaining in popularity. Fluoroscopic studies such as barium follow through and small bowel enteroclysis are being replaced by the cross-sectional alternatives. Contrast-enhanced ultrasound is showing results comparable with CT and MRI, but concern remains regarding reproducibility, especially outside centres that specialize in advanced sonographic techniques.

SUMMARY

CT and MRI enterography are comparable first-line modalities for patients with suspected small bowel disease, but magnetic resonance enterography is favoured given the absence of ionizing radiation. Capsule endoscopy is a reasonable alternative investigation in exploration of chronic gastrointestinal blood loss, but is best kept as a second-line test in patients with other symptoms.

Resection of at-risk mesenteric lymph nodes is associated with improved survival in patients with small bowel neuroendocrine tumors

BACKGROUND

Neuroendocrine tumors of the small intestine commonly metastasize to regional lymph nodes (LNs). Single-institution reports suggest that removal of LNs improves outcome, but comprehensive data are lacking. We hypothesized that the extent of lymphadenectomy reported in a large administrative database would be associated with overall survival for jejunal and ileal neuroendocrine tumors.

METHODS

A search of the Surveillance Epidemiology and End Results database was performed for patients with jejunal and ileal neuroendocrine tumors from 1977 to 2004. Descriptive patient characteristics were collected to include age at diagnosis, sex, race, grade, primary tumor size, LN status, number of LNs resected, presence of distant metastasis, and the type of operation. Statistical analyses were limited to patients with only one primary tumor to exclude patients with other malignancies. Univariate and multivariate analyses were performed to analyze the number of LNs resected and the LN ratio (number of positive LNs/total number of LNs removed) to determine the effect on cancer-specific survival.

RESULTS

Altogether, 1,364 patients were included in this analysis. Removal of any LNs was associated with improved cancer-specific survival when compared to patients with no LN removal reported (p = 0.0027) on univariate analysis. Among those who had any LNs removed, a median of eight LNs were identified in resection specimens with a median LN ratio of 0.29 (range 0-1). On multivariate analysis (adjusting for age and tumor size), patients with >7 LNs removed experienced better cancer-specific survival than those with ≤ 7 LNs removed (median survival not reached vs. 140 months): hazard ratio and 95 % confidence interval were 0.573 (0.402, 0.817) (p = 0.002).

CONCLUSIONS

This review of a large number of surgical patients demonstrates that regional mesenteric lymphadenectomy in conjunction with resection of the primary tumor is associated with improved survival of patients with small bowel neuroendocrine tumors.

Complete response and prolonged disease-free survival in a patient with recurrent duodenal adenocarcinoma treated with bevacizumab plus FOLFOX6

Small bowel adenocarcinoma is an uncommon gastrointestinal malignancy with limited data on effective chemotherapy in the adjuvant setting, as well as for advanced disease. We present a case report of a patient with recurrent duodenal adenocarcinoma after resection and adjuvant chemotherapy who experienced a complete response to bevacizumab with oxaliplatin and 5FU (FOLFOX) followed by bevacizumab/capecitabine maintenance therapy for 2 years. The patient continues to be disease-free 8 years after his recurrence. This case highlights the potential of vascular endothelial growth factor (VEGF) inhibitors to enhance chemotherapeutic regimens for advanced small bowel adenocarcinoma.

Small bowel adenocarcinoma: epidemiology, risk factors, diagnosis and treatment

Small bowel adenocarcinomas are rare tumours, but their incidence is increasing. Their most common primary location is the duodenum. The few studies that have collected data regarding small bowel adenocarcinoma are not homogeneous and are widely spread over time. Even though these tumours are most often sporadic, some predisposing diseases have been identified, among which Crohn's disease and genetic syndromes. Early diagnosis of small bowel adenocarcinoma remains difficult despite significant radiological and endoscopic progress. After surgical resection the main prognostic factor is node invasion; in this case, adjuvant chemotherapy can be expected to be beneficial, although this has not been established by randomised trials. For metastatic disease, platinum-based chemotherapy seems to be the most effective treatment. Targeted therapies have not yet been evaluated in this type of cancer.

MRI-guided laser ablation of neuroendocrine tumor hepatic metastases

BACKGROUND

Neuroendocrine tumors (NET) represent a therapeutically challenging and heterogeneous group of malignancies occurring throughout the body, but mainly in the gastrointestinal system.

PURPOSE

To describe magnetic resonance imaging (MRI)-guided laser ablation of NET liver metastases and assess its role within the current treatment options and methods.

MATERIAL AND METHODS

Two patients with NET tumor hepatic metastases were treated with MRI-guided interstitial laser ablation (LITT). Three tumors were treated. Clinical follow-up time was 10 years.

RESULTS

Both patients were successfully treated. There were no local recurrences at the ablation site during the follow-up. Both patients had survived at 10-year follow-up. One patient is disease-free.

CONCLUSION

MRI-guided laser ablation can be used to treat NET tumor liver metastases but combination therapy and a rigorous follow-up schedule are recommended.

A single institution's experience with surgical cytoreduction of stage IV, well-differentiated, small bowel neuroendocrine tumors

BACKGROUND

Well-differentiated neuroendocrine tumors (NETs) of the gastrointestinal tract are rare, slow-growing neoplasms. Clinical outcomes in a group of stage IV, well-differentiated patients with NETs with small bowel primaries undergoing cytoreductive surgery and multidisciplinary management at a single center were evaluated.

STUDY DESIGN

The charts of 189 consecutive patients who underwent surgical cytoreduction for their small bowel NETs were reviewed. Information on the extent of disease, complications, and Kaplan-Meier survival were collected from the patient records.

RESULTS

A total of 189 patients underwent 229 cytoreductive operations. Ten percent of patients required an intraoperative blood transfusion and 3% (6 of 229) had other intraoperative complications. For all 229 procedures performed, mean (± SD) stay in the ICU was 4 ± 3 days and in the hospital was 9 ± 10 days. Before discharge, 51% of patients had no postoperative complications and 39% of patients had only minor complications. In a 30-day follow-up period from discharge, 85% of patients had no additional complications and 13% had only minor complications. The 30-day postoperative death rate was 3% (5 of 189). Mean survival from histologic diagnosis of NET was 236 months. The 5-, 10-, and 20-year Kaplan-Meier survival rates from diagnosis were 87%, 77%, and 41%, respectively.

CONCLUSIONS

Cytoreductive surgery in patients with well-differentiated midgut NETs has low mortality and complication rates and is associated with prolonged survival. We believe that cytoreductive surgery is a key component in the care of patients with NETs.

Increased incidence of gastrointestinal cancers among patients with pyogenic liver abscess: a population-based cohort study

BACKGROUND & AIMS

The relationship between pyogenic liver abscess (PLA) and gastrointestinal (GI) cancer was first reported more than 20 years ago, yet little is known about this connection. We evaluated this association in a population-based, retrospective, cohort study.

METHODS

Using Taiwan National Health Insurance claims data, we collected data on a cohort of 14,690 patients with PLA diagnosed from 2000 to 2007. A reference cohort of 58,760 persons without PLA (controls) was selected from the same database, frequency matched by age, sex, and index year. Both cohorts were followed up until the end of 2009, and incidences of GI cancer were calculated.

RESULTS

The incidence of GI cancer was 4.30-fold higher among patients with PLA compared with controls (10.8 vs 2.51/1000 person-years). Site-specific analysis showed that the highest incidence of colorectal cancer was among patients with PLA and diabetes mellitus, followed by patients with PLA without diabetes and controls with diabetes (9.58, 5.76, and 1.49/10,000 person-years, respectively). The PLA cohort also had a high risk of small intestine cancer (adjusted hazard ratio [aHR], 12.7; 95% confidence interval [CI], 5.79-27.7) and biliary tract cancer (aHR, 9.56; 95% CI, 6.68-13.7). Their risk of pancreatic cancer (aHR, 2.51; 95% CI, 1.68-3.76) was also significant. However, patients with PLA did not have an increased risk of gastric cancer compared with controls.

CONCLUSIONS

In a population-based study, we found that the incidence of GI cancer is increased more than 4-fold among patients with PLA compared with controls. PLA might therefore be an indicator of GI cancer. Patients with PLA had the highest incidence of colorectal cancer, followed by cancers of the biliary tract, pancreas, and small intestine.

Small intestinal tumours

Objective. Balloon enteroscopy (BE) and capsule enteroscopy (CE) are enteroscopy methods that allow examination and treatment of the small bowel. Before the CE and BE era, the small intestine was difficult to access for investigation. Small intestinal tumours are infrequent conditions, but about half of them are malignant. Materials and Methods. A total of 303 BEs were performed in 179 patients. Oral insertion was performed in 240 and anal in 63 BEs. Indications for the procedure in our patients with small bowel tumours were anaemia and/or bleeding, obstruction, suspicion of carcinoid tumour, or suspicion of Peutz-Jeghers syndrome. Results. In 50 of our 179 patients (28%), we diagnosed some small intestinal tumours: hamartomas in Peutz-Jeghers syndrome in 16 patients, adenocarcinoma in 7, lymphoma in 6, carcinoid tumour in 4, melanoma and stromal tumour in 3, adenoma, lipoma, and inflammatory polyps in 2, and granular cell tumour, cavernous lymphangioma, fibrolipoma, Cronkhite-Canada polyps, and metastatic involvement in individual cases. Conclusion. BE facilitates exploration and treatment of the small intestine. The procedure is generally safe and useful. BE and CE are essential modalities for the management of small intestinal diseases.

Small bowel adenocarcinoma phenotyping, a clinicobiological prognostic study

BACKGROUND

Small bowel adenocarcinoma (SBA) is a rare tumour with a poor prognosis. Molecular biology data on SBA carcinogenesis are lacking.

METHODS

Expression of HER2, β-catenin, p53 and mismatch repair (MMR) protein was assessed by immunohistochemistry. KRAS, V600E BRAF mutations and microsatellite instability were investigated.

RESULTS

We obtained samples from 63 SBA patients (tumour stages: I-II: 30%; III: 35%; IV: 32%; locally advanced: 3%). HER2 overexpression (3+) was observed in 2 out of 62 patients, overexpression of p53 in 26 out of 62, abnormal expression of β-catenin in 12 out of 61, KRAS mutation in 21 out of 49, BRAF V600E mutation in 1 out of 40 patients, MMR deficiency (dMMR) in 14 out of 61 and was consistent with Lynch syndrome in 9 out of 14 patients. All of the dMMR tumours were in the duodenum or jejunum and only one was stage IV. Median overall survival (OS) was 36.6 months (95% CI, 26.9-72.2). For all patients, in univariate analysis, stages I-II (P<0.001), WHO PS 0-1 (P=0.01) and dMMR phenotype (P=0.02) were significantly associated with longer OS. In multivariate analysis, disease stage (P=0.01) and WHO PS 0-1 (P=0.001) independently predicted longer OS. For stage IV patients, median OS was 20.5 months (95% CI: 14.6; 36.6 months). In multivariate analysis, WHO PS 0-1 (P=0.0001) and mutated KRAS status (P=0.02) independently predicted longer OS.

CONCLUSION

This large study suggests that molecular alterations in SBA are closer to those in colorectal cancer (CRC) than those in gastric cancer, with low levels of HER 2 overexpression and high frequencies of KRAS mutations. The seemingly higher frequency of dMMR than in CRC may be explained by the higher frequency of Lynch syndrome in SBA patients. A dMMR phenotype was significantly associated with a non-metastatic tumour (P=0.02). A trend for a good prognosis and a duodenum or jejunum primary site was associated with dMMR.

Quality of life, resource utilisation and health economics assessment in advanced neuroendocrine tumours: a systematic review

Neuroendocrine tumours (NET) are often diagnosed at an advanced stage when the prognosis is poor for patients, who often experience diminished quality of life (QoL). As new treatments for NET become available, it is important to characterise the associated outcomes, costs and QoL. A comprehensive search was performed to systematically review available data in advanced NET regarding cost of illness/resource utilisation, economic studies/health technology assessment and QoL. Four rounds of sequential review narrowed the search results to 22 relevant studies. Most focused on surgical procedures and diagnostic tools and contained limited information on the costs and consequences of medical therapies. Multiple tools are used to assess health-related QoL in NET, but few analyses have been conducted to assess the comparative impact of available treatment alternatives on QoL. Limitations include English language and the focus on advanced NET; ongoing terminology and classification changes prevented pooled statistical analyses. This systematic review suggests a lack of comparative economic and outcomes data associated with NET treatments. Further research on disease costs, resource utilisation and QoL for patients with advanced NET is warranted.

S100A4 expression is a prognostic indicator in small intestine adenocarcinoma

AIMS

Due to the rarity of small intestine adenocarcinoma (SIAC), estimating the prognosis for patients with surgically resected SIAC is difficult. Overexpression of S100A4 has been linked to worse patient survival in several malignant neoplasms, but its significance in SIAC has not been determined.

METHODS

S100A4 protein expression was assessed in 197 surgically resected SIAC cases and compared with clinicopathological factors, including patient survival.

RESULTS

A progressive increase in S100A4 labelling was observed in normal intestinal epithelium, adenoma and adenocarcinoma (p<0.001), and 50 SIAC cases (26.2%) showed strong S100A4 expression. Patients with SIAC with strong S100A4 expression had a higher pT classification (p=0.05), as well as increased lymph node metastasis (p=0.009) and perineural invasion (p=0.002). Patients with SIAC with strong S100A4 expression had significantly worse survival (median survival, 21 months) than those with weak/no S100A4 expression (42.5 months) by univariable (p=0.04) and multivariable (p=0.01) analyses.

CONCLUSIONS

S100A4 overexpression is observed in a subset of SIACs, is associated with advanced disease and can be used as a prognostic indicator of poor prognosis in patients with SIAC.

Small bowel adenocarcinomas--existing evidence and evolving paradigms

Small bowel cancers account for 3% of all gastrointestinal malignancies and small bowel adenocarcinomas represent a third of all small bowel cancers. Rarity of small bowel adenocarcinomas restricts molecular understanding and presents unique diagnostic and therapeutic challenges. Better cross-sectional imaging techniques and development of enteroscopy and capsule endoscopy have facilitated earlier and more-accurate diagnosis. Surgical resection remains the mainstay of therapy for locoregional disease. In the metastatic setting, fluoropyrimidine and oxaliplatin-based chemotherapy has shown clinical benefit in prospective non-randomized trials. Although frequently grouped under the same therapeutic umbrella as large bowel adenocarcinomas, small bowel adenocarcinomas are distinct clinical and molecular entities. Recent progress in molecular characterization has aided our understanding of the pathogenesis of these tumours and holds potential for prospective development of novel targeted therapies. Multi-institutional collaborative efforts directed towards cogent understanding of tumour biology and designing sensible clinical trials are essential for developing improved therapeutic strategies. In this Review, we endeavour to outline an evidence-based approach to present-day management of small bowel adenocarcinoma, describe contemporary challenges and uncover evolving paradigms in the management of these rare 'orphan' neoplasias.

A large prospective study of risk factors for adenocarcinomas and malignant carcinoid tumors of the small intestine

PURPOSE

Small intestinal cancer is increasing in the U.S.A, yet little is known about its etiology. Our aim was to prospectively evaluate risk factors for this malignancy by the two main histologic subtypes (adenocarcinomas and carcinoids).

METHODS

Hazard ratios and 95% confidence intervals (CI) were estimated for all incident small intestinal cancers (n = 237), adenocarcinomas (n = 84), and malignant carcinoids (n = 124), by demographic and lifestyle factors among 498,376 men and women.

RESULTS

Age was the only risk factor for adenocarcinomas (HR for ≥ 65 vs. 50-55 years = 3.12, 95% CI 1.33, 7.31). Age (HR for ≥ 65 vs. 50-55 years = 3.31, 95% CI 1.51, 7.28), male sex (HR = 1.44, 95% CI 1.01, 2.05), body mass index (BMI, HR for ≥ 35 vs. 18.5-< 25 kg/m2 = 1.95, 95% CI 1.06, 3.58), and current menopausal hormone therapy use (HR = 1.94, 95% CI 1.07, 3.50) were positively associated with malignant carcinoids. A family history of any cancer or colorectal cancer (HR = 1.42, 95% CI 0.99, 2.03; 1.61, 0.97, 2.65, respectively), or a personal history of colorectal polyps (HR = 1.51, 95% CI 0.92, 2.46) produced elevated, but not statistically significant, risks for malignant carcinoids. Race, education, diabetes, smoking, physical activity, and alcohol intake were not associated with either histologic subtype.

CONCLUSIONS

Risk factors differed according to cancer subtype; only age was associated with adenocarcinomas, whereas age, male sex, BMI, and menopausal hormone therapy use were positively associated with malignant carcinoids.

Small bowel carcinoid: Location isn’t everything!

AIM: To investigate the prognostic significance of the primary site of disease for small bowel carcinoid (SBC) using a population-based analysis.

METHODS: The Surveillance, Epidemiology and End Results (SEER) database was queried for histologically confirmed SBC between the years 1988 and 2009. Overall survival (OS) and disease-specific survival (DSS) were analyzed using the Kaplan-Meier method and compared using Log rank testing. Log rank and multivariate Cox regression analyses were used to identify predictors of survival using age, year of diagnosis, race, gender, tumor histology/size/location, tumor-node-metastasis stage, number of lymph nodes (LNs) examined and percent of LNs with metastases.

RESULTS: Of the 3763 patients, 51.2% were male with a mean age of 62.13 years. Median follow-up was 50 mo. The 10-year OS and DSS for duodenal primaries were significantly better when compared to jejunal and ileal primaries (P = 0.02 and < 0.0001, respectively). On multivariate Cox regression analysis, after adjusting for multiple factors, primary site location was not a significant predictor of survival (P = 0.752 for OS and P = 0.966 DSS) while age, number of primaries, number of LNs examined, T-stage and M-stage were independent predictors of survival.

CONCLUSION: This 21-year, population-based study of SBC challenges the concept that location of the primary lesion alone is a significant predictor of survival.

The effects of chemotherapy on primary small bowel cancer: A retrospective multicenter observational study in Japan

Small bowel cancer is relatively rare among gastrointestinal tract cancers, including esophageal, gastric and colorectal cancers. The majority of cases of small bowel cancer are diagnosed at an advanced stage, resulting in poor outcomes. The clinical effects of chemotherapy on small bowel cancer have been investigated in a limited number of studies from Europe and the USA. However, they have not yet been fully investigated in Asian countries, including Japan. This retrospective multicenter observational study was designed to investigate the efficacy of chemotherapy on small bowel cancer. A questionnaire survey was conducted in 28 hospitals affiliated with the Osaka University Hospital. We retrospectively reviewed the medical records of 61 patients with small bowel cancer (32 patients who were unable to undergo curative resection or had unresectable distant metastases and 29 who underwent curative resection), treated between 1996 and 2009, to evaluate the outcomes and the efficacy of chemotherapy. There was no significant difference in the overall survival between the patients undergoing curative resection with postoperative adjuvant chemotherapy and those without postoperative adjuvant chemotherapy. In patients with non-curative resection or unresectable distant metastases, the response rate to chemotherapy was 31.6% and the overall survival was significantly higher compared to that without chemotherapy (P=0.008). The study results suggested that chemotherapy is effective for Japanese patients with small bowel cancer who cannot undergo curative resection or have unresectable distant metastases.