Primary malignant tumors in the small bowel: a comparison of the small-bowel enema and conventional follow-through examination

Surgical Resection of Metastatic Malignant Small Bowel Obstruction

Small bowel cancer is a rare cause of small bowel obstruction (SBO) that is often discovered too late, leading to a poor prognosis at diagnosis. This case describes an African American patient with a previous history of abdominal surgery who presented to the emergency department with a partial small bowel obstruction (PSBO) that failed to resolve with conservative measures, therefore requiring surgical intervention. An exploratory laparoscopy revealed a firm apple core mass obstructing the lumen of the proximal jejunum 20 cm from the ligament of Treitz. The involved portion of the small bowel was resected with wide margins and sent to pathology. The small bowel was reconstructed by a functional end-to-end anastomosis, and the patient was admitted for observation until the return of bowel function. The pathology report, returned four weeks after the patient's discharge, reported metastatic adenocarcinoma originating from the small intestine. The patient was referred to oncology for further management of his metastatic cancer. Small bowel cancer, although rare, should always be part of the differential diagnosis in the case of small bowel obstruction. If cancer is suspected during exploratory surgery, the entire peritoneal cavity should be explored, and oncologic bowel resection should be performed with adequate margins. Final staging then occurs in the postoperative period.

Performance of Multidetector Computed Tomography and Negative Versus Positive Enteric Contrast for Evaluation of Gastrointestinal Neuroendocrine Neoplasms

BACKGROUND

Routine computed tomography (CT) scans are thought to have poor performance for detection of gastrointestinal (GI) neuroendocrine neoplasms (NENs), which leads to delayed workup. Detection of even 1 bowel tumor can guide diagnostic workup and management. The purposes of this study were to assess the accuracy of multidetector computed tomography (MDCT) and to compare negative versus positive enteric contrast in detecting at least 1 GI tumor per patient with suspected or confirmed diagnosis of a NEN.

METHODS

This retrospective study included 107 patients with intravenous and oral contrast (65 positive, 40 negative, and 2 no oral contrast) abdominopelvic MDCT. Two abdominal radiologists independently analyzed the CTs for detection and localization of bowel NENs. Surgical pathology was considered the reference standard. Analyses included κ and summary statistics, McNemar test, Pearson χ2 test, and Fisher exact test.

RESULTS

Among the 107 CT scans, there were 30 pathology negative studies and 77 studies with positive pathology for GI NEN. Interreader agreement for CT evaluation was substantial (κ = 0.61). At least 1 GI NEN per patient was detected with 51% to 53% sensitivity, 87% to 93% specificity, 91% to 95% positive predictive value (PPV), 42% negative predictive value, and 63% accuracy for each reader, and 57% accuracy when only the concordant (ie, matching) results of the 2 readers were considered. Computed tomography scans with negative enteric contrast had significantly higher sensitivity for concordant results than CTs with positive enteric contrast (58% vs 30%, P = 0.01). Specificity (100% vs 95%, P = 0.5), PPV (100% vs 93%, P = 0.49), negative predictive value (39% vs 39%, P = 0.99), and accuracy (67% vs 51%, P = 0.10) were not significantly different for negative versus positive enteric contrast for the concordant results. There was no significant difference in GI NEN localization between the readers.

CONCLUSIONS

Routine MDCT with either positive or negative enteric contrast can detect at least 1 GI tumor per patient with more than 90% PPV and more than 50% accuracy in patients suspected of GI NEN. Using negative enteric contrast improves sensitivity for GI NEN versus positive enteric contrast. In addition, there is high accuracy in localizing the bowel tumor with positive or negative enteric contrast, which may guide surgery. Radiologists should have heightened awareness that evaluating such scans closely may lead to detection of primary bowel NENs at a higher rate than previously reported.

Pediatric Neuroendocrine Carcinoid Tumors: Review of Diagnostic Imaging Findings and Recent Advances

OBJECTIVE

Although rare, pediatric neuroendocrine tumors including carcinoid tumor have increased in incidence over the past few decades. Despite increased recognition, survival rates have not significantly improved. Earlier detection of these tumors is necessary to improve clinical outcomes. This article discusses imaging approaches for detecting pediatric carcinoid tumors including anatomic imaging methods such as CT and MRI as well as functional imaging methods targeting the somatostatin receptor including ¹¹¹In-labeled octreotide and newer ⁶⁸Ga-based radiotracers that may hold promise in hybrid PET/CT or PET/MRI.

CONCLUSION

Improvements in functional imaging with novel somatostatin receptor-specific radiotracers along with fused functional and anatomic imaging have substantially improved the clinical detection of carcinoid tumors. Although rare, these tumors are encountered in children, and an awareness of the appropriate use of various imaging methods is essential for pediatric specialists. Further research is needed to ascertain the diagnostic value of newer imaging methods and radiotracer-based treatment approaches, especially in the pediatric population.

Adenocarcinoma of Small Bowel

Small bowel cancer is one of the rarest cancers in the gastrointestinal tract. The diagnosis is usually late and most patients presented with the advanced stage. Because of this rarity, there is limited data when making decisions for treatment and biological behavior. Most forms of the cancer occur in the duodenum with surgery being the treatment of choice if the cancer is operable. Chemotherapy has an accepted role in duodenal cancer, with the best form being regimen, which yields the best result in combination with capecitabin and oxaliplatin. Our case patient was present with liver metastasis and a huge mass in her first duodenal region so we were required to use chemotherapy and radiotherapy. Like other duodenal cancers, the metastasis decreased her survival and she died about 13 months after diagnosis.

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.

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.

Small Bowel Imaging: Clinical Applications of the Different Imaging Modalities—A Comprehensive Review

In the last years, MR and CT techniques have been optimized for small bowel imaging and are playing an increasing role in the evaluation of small bowel disorders. In comparison to traditional barium fluoroscopic examinations, spatial and temporal resolution is now much more improved partially thanks to modern bowel distending agents. However, there is a global interest in implementing techniques that either reduce or eliminate radiation exposure. This is especially important in patients with chronic diseases such as inflammatory bowel disease who may require multiple studies over a lifetime. Owing to the excellent soft tissue contrast, direct multiplanar imaging capabilities, new ultrafast breath-holding pulse sequences, lack of ionizing radiation, and availability of a variety of oral contrast agents, MR is well suited to play a critical role in the imaging of small bowel disorders.

Jejunal adenocarcinoma: an elusive diagnosis

Tubercular stricture of small bowel is a common cause of subacute intestinal obstruction in India. In a small subset of patients the cause of the intestinal obstruction could be adenocarcinoma of jejunum. It is difficult to diagnose preoperatively. The point of concern is compared to tubercular stricture, the treatment of jejunal adenocarcinoma is always surgical in the form of cancer directed surgery. The operating surgeon needs to have a very high suspicion for jejunal adenocarcinoma because the timely treatment offers the best survival in otherwise an aggressive disease with bleak prognosis.

Developing a new measure of small bowel peristalsis with dynamic MR: a proof of concept study

BACKGROUND

Small bowel peristalsis is a complex of many individual motion elements. Although each element of peristalsis can be measured there is no current global measure of peristalsis.

PURPOSE

To examine the feasibility of automated computerized assessment of global small bowel motility using simple computational methods.

MATERIAL AND METHODS

Coronal dynamic MR images were obtained from five healthy volunteers who had fasted for 9 h and drunk 1.5 L of water. Images were taken using single breath-hold and ECG triggering. Acquisitions were repeated at 10 and 20 min after an intramuscular injection of hyoscine butylbromide. Parametric maps were generated representing the mean change in signal amplitude (MSA) per voxel for each dynamic acquisition. Two observers independently assessed thresholding for optimal segmentation of small bowel from other sources of signal. Total voxel activity (TVA) for each study was calculated as a sum of MSA per slice and whole examination and TVA profiles were generated.

RESULTS

Independent observations suggest that the automated segmentation method described usefully segments small bowel activity from other signal. Small bowel movement represented as TVA varied three-fold in the five volunteers and was inhibited by anti-muscarinic injection.

CONCLUSION

It is possible to develop a new measure, based on automated segmentation of mean signal amplitude changes, of small bowel peristalsis using dynamic MR.

Small bowel adenocarcinoma - report of two cases and review of literature

Although accounting for 90 % of the intestinal surface area, small bowel adenocarcinomas are not common. The majority of these lesions are incidentally detected during laparotomy for intestinal obstruction or perforation. The symptoms associated with these lesions are not very specific and preoperative diagnosis is rare. We report two cases of jejunal adenocarcinomas detected in patients undergoing laparotomy for acute abdomen and review the literature for small bowel adenocarcinomas.

Small bowel endoscopy and Peutz-Jeghers syndrome

Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant inherited disease. It is clinically characterized by the development of gastrointestinal hamartomas, mainly located in the small bowel. These hamartomas are prone to complications such as intussusceptions, abdominal complaints and anaemia. Furthermore, patients are at increased risk for developing small bowel cancer. Therefore, regular surveillance of the small bowel is indicated. However, the optimal strategy for surveillance has not been determined yet. This review gives an overview of the different techniques that have been described to examine the small bowel of PJS patients. First, a number of radiologic and endoscopic imaging modalities with diagnostic value are discussed. Secondly, recently developed advanced endoscopy techniques are described that can serve both as a diagnostic and therapeutic tool in the surveillance of the small bowel. Finally, a recommendation is given how to apply these individual techniques for small bowel surveillance in a step-up approach.

Current advance in small bowel tumors

Small intestinal tumors are difficult challenge to gastroenterologists. The difficulty in making a diagnosis of small intestinal tumor lies in the relative inaccessibility and absence of typical presentation. New endoscopic and radiologic technologies provide clear and fine anatomical visualization of the small bowel and are approved to improve the diagnostic sensitivity and accuracy. Patients at risk of small intestinal tumors might gain a benefit from proper surveillance with this new technology. Minimally invasive therapy is now available with advance of balloon assisted enteroscopy. This review describes the general aspect of the small intestinal tumors, focusing on the new modalities for diagnosis.

[Surgical interventions for small bowel tumors at our department in the last 3 years]

Adenocarcinoma of the small intestine is a rare type of cancer in Hungary as well as in the world. It is more commonly found in patients with coeliac disease (lymphoma) and in hereditary bowel cancer syndromes (hereditary non-polyposis colorectal cancer, familial adenomatous polyposis, and Peutz-Jegher syndrome). Due to the relatively featureless presentation there is usually a few months delay in diagnosis of the disease In addition, small bowel cancer is frequently diagnosed on laparotomy only. We analyzed the small bowel malignancies treated in our department in the last 3 years from the point of view of incidence, preoperative evaluation, surgical intervention, and pathology. All patients were admitted as emergencies, so they underwent rapid investigations, and emergency or semi-emergency surgical interventions. Importantly, preoperative investigations helped to establish operative indication only rather than providing exact diagnosis. The operative procedure was small bowel resection in all cases. Pathological diagnosis included GIST, adenocarcinoma, and non-Hodgkin lymphoma as well.

MR enteroclysis in the diagnosis of small-bowel neoplasms

PURPOSE

To evaluate the diagnostic accuracy and interobserver variance of magnetic resonance (MR) enteroclysis in the diagnosis of small-bowel neoplasms, with small-bowel endoscopy, surgery, histopathologic analysis, and follow-up serving as standards of reference, and to identify MR enteroclysis characteristics capable of enabling discrimination between benign and malignant small-bowel neoplasms.

MATERIALS AND METHODS

This study was performed in accordance with the guidelines of the institutional review board, and the requirement for informed consent was waived. MR enteroclysis studies of 91 patients (43 women, 48 men; age range, 18-83 years) were retrospectively evaluated by two radiologists blinded to clinical details. Only studies explicitly performed to investigate or exclude the presence of small-bowel neoplasms were included. Radiologic findings were compared with findings of double-balloon endoscopy (n = 45), surgery (n = 18), esophagogastroduodenoscopy (n = 3), ileocolonoscopy (n = 2), autopsy (n = 2), and clinical follow-up for more than 18 months (n = 21). Efficacy parameters were calculated with 95% confidence intervals. Tumor characteristics were compared with the Student t test and the Fisher exact test.

RESULTS

Readers 1 and 2 interpreted 31 and 33 studies, respectively, as depicting a small-bowel neoplasm and 19 and 17 studies, respectively, as depicting small-bowel malignancy. In 32 patients, the presence of small-bowel neoplasm was confirmed. In 19 of these patients, the neoplasm was malignant. Sensitivity and specificity in the diagnosis of small-bowel neoplasms was 0.91 and 0.95, respectively, for reader 1 and 0.94 and 0.97, respectively, for reader 2; the kappa value was 0.95. Factors associated with malignancy were the presence of longer solitary nonpedunculated lesions, mesenteric fat infiltration, and enlarged mesenteric lymph nodes.

CONCLUSION

Eighty-six of 91 studies were correctly interpreted, resulting in an overall diagnostic accuracy of 0.95 for MR enteroclysis in the detection of small-bowel neoplasms.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.09090828/-/DC1.

Comprehensive review of small bowel metastasis from head and neck squamous cell carcinoma

Secondary tumours of small intestine account for 10% of all small bowel cancers. The most common sites of primary tumour metastasizing to small bowel are uterus, cervix, colon, lung, breast and melanoma. The majority of these metastatic tumours come from adenocarcinoma primaries; squamous cell carcinoma constitutes a very small proportion of all metastatic small intestinal lesions. Metastasis to small bowel by head and neck squamous cell carcinoma is extremely rare and carries an unfavourable prognosis. Owing to the limited number of published studies, its characteristic features, clinical presentation and outcomes are poorly described. This work aims at specifying these characteristics by reviewing, compiling, analysing and reporting all published cases in the published literature on small bowel metastasis secondary to head and neck squamous cell carcinoma. To the best of our knowledge, this is the first comprehensive review article on the small intestinal metastasis from head and neck squamous cell carcinoma.

Adenocarcinoma of the small bowel: a surgical dilemma

Malignant tumors of the small intestine are among the rarest types of gastrointestinal cancers. Due to their infrequent occurrence and the multitude of tumor types (viz, adenocarcinomas, carcinoids, sarcomas, and lymphomas), not much is known about their natural history and presentation, and there is often delay in the diagnosis. Adenocarcinoma is the commonest histologic type of small bowel cancer. There are no prospective randomized trials that have elucidated the best diagnostic and therapeutic options for this rare condition. In this article, a case of adenocarcinoma of the jejunum presenting as an abdominal lump is presented, along with a review of the literature.

Adenocarcinoma of the small bowel: a surgical dilemma

Malignant tumors of the small intestine are among the rarest types of gastrointestinal cancers. Due to their infrequent occurrence and the multitude of tumor types (viz, adenocarcinomas, carcinoids, sarcomas, and lymphomas), not much is known about their natural history and presentation, and there is often delay in the diagnosis. Adenocarcinoma is the commonest histologic type of small bowel cancer. There are no prospective randomized trials that have elucidated the best diagnostic and therapeutic options for this rare condition. In this article, a case of adenocarcinoma of the jejunum presenting as an abdominal lump is presented, along with a review of the literature.

Enteroscopy and its relationship to radiological small bowel imaging

The field of radiological small bowel imaging is changing rapidly, as is small bowel enteroscopy. New techniques allow the depiction of intraluminal, mural, and extraintestinal features of various small bowel disorders, such as Crohn disease, small bowel polyposis syndromes, small intestinal malignancies, and celiac disease. For patients requiring repeated small bowel imaging, modalities that do not use ionizing radiation, such as ultrasound or magnetic resonance imaging, should be considered.

Normal small bowel wall characteristics on MR enterography

PURPOSE

To assess the normal small bowel parameters, namely bowel diameter, bowel wall thickness, number of folds (valvulae connivientes) per 2.5 cm (in.), fold thickness and interfold distance per small bowel segment (duodenum, jejunum, proximal ileum, distal ileum and terminal ileum) on MR enterography.

MATERIALS AND METHODS

Between September 2003 and January 2008, 280 MR enterography examinations were performed for investigation of known or suspected small bowel pathology. 120 of these examinations were normal. Sixty-five (m=29, f=36, mean age=34 years, range=17-73 years) of 120 examinations without a prior small bowel diagnosis, with no prior or subsequent abnormal radiology or endoscopy examinations, no prior small bowel surgery and with a minimum 3 years follow-up demonstrating normality were retrospectively evaluated for the described small bowel parameters.

RESULTS

We found the mean diameter of the duodenum to be 24.8mm (S.D.=4.5mm), jejunum to be 24.5mm (S.D.=4.2mm), proximal ileum to be 19.5mm (S.D.=3.6mm), distal ileum to be 18.9 mm (S.D.=4.2mm) and terminal ileum to be 18.7 mm (S.D.=3.6mm). The number of folds per 2.5 cm varied from 4.6 in the jejunum to 1.5 in the terminal ileum. The fold thickness varied from 2.1mm in the duodenum to 1.8mm in the terminal ileum. The small bowel parameters gradually decreased in size from the duodenum to the smallest measurements which were in the terminal ileum. The bowel wall is similar in size throughout the small bowel measuring 1.5+/-0.5mm.

CONCLUSION

These results provide the mean, range of normality and standard deviation of the small bowel parameters per segment on the current population on MR enterography. From our experience, knowledge of these parameters is extremely helpful and essential in the everyday assessment of MR enterography studies.

Multidetector CT in small-bowel neoplasms

PURPOSE

The aim of this study was to assess the diagnostic potential of multidetector computed tomography (MDCT) in the evaluation of small-bowel neoplasms.

MATERIALS AND METHODS

We studied 120 patients with suspected small-bowel disease by 16-slice MDCT after oral administration of a polyethylene glycol solution (n=56) or methylcellulose via a nasojejunal tube (n=64). Unenhanced and contrast-enhanced CT was performed. Contrast-enhanced CT images were acquired 40 s after IV injection of 130 ml of iodinated contrast agent at a rate of 3 ml/s. Multiplanar reconstructions were performed at the end of the examinations.

RESULTS

Fifteen patients were found to be affected by small-bowel neoplasm (six had non-Hodgkin's lymphoma, three had carcinoid tumour, two had Peutz-Jeghers syndrome, two had adenocarcinoma, two had melanoma metastases, one had lipoma). In the remaining patients, 58 cases of Crohn's disease and seven miscellaneous diseases were detected. All findings were confirmed by barium studies, surgery or endoscopy.

CONCLUSIONS

MDCT performed after bowel-loop distension with low-density contrast material and IV administration of iodinated contrast agent is a reliable method for diagnosing and staging small-bowel neoplasms.

The patient with recidivent obscure gastrointestinal bleeding

Obscure gastrointestinal (GI) bleeding is defined as visible or invisible GI blood loss, the source of which can not be identified by standard endoscopy (oesophagogastroduodenoscopy and colonoscopy). Nowadays, GI bleeding is divided into upper, mid- and lower bleeding. Mid-GI bleeding covers the section from the Treitz ligament to the ileocaecal valve. The new diagnostic methods of capsule endoscopy and double balloon enteroscopy have revolutionised the diagnostic approach in recent years. As a result, previous radiological and nuclear medicine techniques (small bowel X-ray, scintigraphy and angiography), but also endoscopic techniques, such as the push enteroscopy and intraoperative endoscopy, are becoming less important. After standard endoscopy and persistent blood loss it is advisable to first have these procedures repeated by an experienced examiner under optimal conditions. Nevertheless, no source of bleeding is identified by this method in 5% of cases. It is then recommended to use capsule endoscopy and, depending on the findings, double balloon enteroscopy with the option of intervention. In patients with unstable circulation an invasive procedure (intraoperative endoscopy) may be required.

Small bowel tumors

WCE is a noninvasive diagnostic technique that visualizes the entire small intestine and identifies lesions in parts of the small bowel not reached by traditional endoscopy. Although further studies are needed to define the exact role of WCE for diagnosing and managing small bowel tumors, its sensitivity has been shown to be superior to PE and small bowel follow-through in regard to diagnosing patients who have obscure GI bleeding, the most common indication for capsule endoscopy in the authors' series of patients with documented small bowel tumors. As more material is published, capsule endoscopy likely will be confirmed to be the diagnostic procedure of choice in patients with suspected small bowel tumors.

Small intestinal metastasis from small cell lung cancer

A 71-year-old man who had small cell lung cancer was referred to our institution. Before starting chemotherapy, anemia progressed and stool examination was positive for occult blood. An abdominal computed tomography scan with contrast medium enhancement of the gastrointestinal tract disclosed a small intestinal tumor. Histological examination after the surgery confirmed that the tumor was metastasis of lung cancer. The patient survived for 3 years after the resection. Although clinically apparent metastases of lung cancer to the small intestine are rare and are reported to have a poor prognosis, early detection and intervention might enhance the chance of survival.

Obscure gastrointestinal bleeding

Obscure GI bleeding is a relatively common problem facing internists, gastroenterologists, and surgeons in a typical clinical practice. The etiology is occasionally suggested by the patient's age, history, and medications. Management is complicated and typically requires a team-oriented approach, with input from the internist, gastroenterologist, radiologist, and surgeon alike. SBFT and enteroclysis seem to have a limited role, unless there is a high suspicion of a small bowel mass lesion or Crohn's disease. Scintigraphy may be performed in patients with active bleeding in whom endoscopy has failed oris contraindicated. Angiography may be used in patients with an early positive nuclear imaging or failed endoscopic therapy. Provocative angiography probably has a lower diagnostic yield than previously reported, and should be performed only in experienced centers. Helical CT is a new and potentially important option in patients with obscure bleeding, but is currently considered experimental. All patients with obscure GI bleeding should undergo repeat upper endoscopy and perhaps colonoscopy to rule out missed lesions. SBE seems to be complementary to capsule endoscopy, and it is unknown whether this should be performed before capsule endoscopy or only if capsule endoscopy yields a positive proximal small bowel finding. Double balloon enteroscopy seems promising, but the technique requires further study. Surgery should be reserved for patients who have a positive capsule endoscopy requiring surgical therapy or patients who have persistent GI bleeding requiring recurrent blood transfusions in whom all other modalities have failed. Treatment for vascularectasias, the most common cause of obscure GI bleeding, is currently inadequate,and typically requires a combination of multiple management approaches.

Imaging of small bowel disease: comparison of capsule endoscopy, standard endoscopy, barium examination, and CT

Capsule endoscopy is a revolutionary new diagnostic tool for the detection of small bowel disease. As the name implies, capsule endoscopy makes use of a swallowable video capsule; as such, it is the only technique that allows noninvasive endoscopic examination of the entire small bowel without sedation. Obscure gastrointestinal bleeding is the most common indication for capsule endoscopy, which commonly depicts arteriovenous malformations, small bowel tumors, and ulcers missed at standard endoscopy and imaging examinations. However, capsule endoscopy is not optimal for the localization of small bowel lesions. In addition, lesions can be missed due to poor bowel preparation, rapid or delayed small bowel transit, or orientation of the camera away from a lesion. Computed tomography and barium examinations are useful for detecting these missed lesions and for localizing lesions detected at capsule endoscopy. Other limitations of capsule endoscopy are the inability to treat lesions and its limited use in patients with small bowel strictures or obstruction. Nevertheless, this new technique is easy to perform, is well tolerated by patients, and, for the first time, allows noninvasive endoscopic evaluation of the entire small bowel.

Multidetector computed tomography enteroclysis (MDCT-E) with neutral enteral and IV contrast enhancement in tumor detection

The aim of our study was to evaluate the reliability of MDCT-enteroclysis (MDCT-E), an emerging technique of small bowel examination that combines the advantages of MDCT examination of the abdomen and the enteral volume challenge of enteroclysis, in evaluation of small bowel neoplasms. In our institutions, MDCT-E was used to study 456 patients (age range 21-84 years, mean 53 years) admitted for suspicion of small bowel disease. All examinations were done on multichannel CT units, 129 on a 16-slice scanner and 327 on a four-slice scanner. Post-processing and multiplanar reformatting and interpretation were performed on dedicated workstations. After adequate gastrointestinal preparation and naso-enteric intubation, small bowel was distended by methylcellulose infused by a peristaltic pump. One volumetric MDCT acquisition was obtained after 120-130 ml of intravenous contrast medium. Multiplanar reformatting was based on the image reconstruction parameters from 3 to 4 mm. Forty-five small bowel neoplasms were found; in the remaining cases, 223 Crohn's diseases and 149 other abnormalities were detected. All findings were confirmed by surgery, endoscopy or clinical follow-up. In our experience, MDCT-E with neutral enteral and IV contrast seems to be a reliable method in the diagnosis of small bowel neoplasms.

A retrospective review of enteroclysis in patients with obscure gastrointestinal bleeding and chronic abdominal pain of undetermined etiology

Our purpose was to determine the diagnostic utility of enteroclysis in the evaluation of obscure gastrointestinal bleeding and abdominal pain of unknown etiology. This is a retrospective review of 97 consecutive patients (mean age, 54.1+/-17.5 [SD] years; 49 male and 48 female) who underwent enteroclysis at Temple University Hospital from January 1994 to October 2001 for the evaluation of obscure GI bleeding or chronic abdominal pain of undetermined etiology. Prior to enteroclysis all patients had an EGD and colonoscopy, which were nondiagnostic for their symptoms. Sixty-three patients (64.9%) had enteroscopy performed prior to enteroclysis that was also negative. Enteroclysis results were defined as positive based on anatomical or functional abnormalities. Analysis of the data included the percentage yield of positive exams, the percentage of positive results per symptom category, and the percentage of patients with a change in clinical management based on positive enteroclysis results. Ninety-seven patients underwent enteroclysis. The indications for enteroclysis were obscure GI bleeding in 67 patients (69.1%) and chronic abdominal pain in 30 patients (30.9%). The number of positive exams was 19 (19.6%). Fourteen of the 67 patients with the indication of GI bleeding had a positive exam (21%), while 5 of the 30 patients with chronic abdominal pain had a positive result (16.7%). There was a change in clinical management due to the enteroclysis results in 10 patients: 7 patients with GI bleeding (10%) and 3 patients with chronic abdominal pain (10%). Positive enteroclysis findings included adhesions (7), filling defects and masses (5), strictures (2), small bowel diverticulosis (1), mucosal abnormalities (3), and a motility disorder (1). The overall positive yield for enteroclysis was 19.6%, with a yield of 16.7% for chronic abdominal pain and 21% for gastrointestinal bleeding. Enteroclysis results changed the clinical management in approximately 10% of the patients.

Small Bowel Adenocarcinoma: A Rare but Aggressive Disease

Unlike the colon and rectum, the small intestine is associated with a very low rate of tumor occurrence. Adenocarcinomas represent the most frequent of these rare digestive tumors and are often fatal as a result of tardy diagnosis. Regardless of the stage, surgery usually remains the cornerstone of small bowel adenocarcinoma therapy. Because of the rarity of the disease, very few significant clinical trials have identified any efficient nonsurgical treatment; however, recent data indicate these tumors might be sensitive to chemotherapy alone or in association with radiation therapy. Conversely, a great deal of progress has been achieved in diagnosis of the tumor, whether by adaptation of existing techniques or development of new ones. We reviewed the clinical aspects of this rare but aggressive disease, focusing on new diagnostic procedures as well as on recent advances in their therapeutic management.

Small bowel tumours: a 10 year experience in four sydney teaching hospitals

BACKGROUND

Small bowel tumours are uncommon and can have a long delay prior to diagnosis. The present study aims to compare the use of computed tomography (CT) and contrast small bowel series (SBS) in their diagnosis and to outline the clinical features of small bowel tumours.

METHODS

A retrospective, case note study was conducted between 1990 and 2000 in four Sydney teaching hospitals. The data collected included clinical features, investigations and tumour characteristics.

RESULTS

One hundred and sixty-six people with small bowel tumours were identified (91 malignant; 75 benign). Malignant tumours consisted of adenocarcinomas (31%), carcinoid tumours (12%), lymphomas (7%) and leiomyosarcomas (5%). Benign tumours consisted of adenomas (22%), hamartomas (13%), leiomyomas (4%), inflammatory polyps (4%) and hyperplastic polyps (2%) and a benign schwannoma (1%). Adenocarcinomas were mainly located in the duodenum (P < 0.001) and carcinoid tumours in the ileum (P < 0.001). Malignant tumours were associated with a higher proportion of symptoms (P < 0.01), signs (P < 0.001) and episodes of small bowel obstruction (P < 0.01). Abdominal CT scans demonstrated a greater sensitivity (87.7%) than SBS (72.9%) with a slightly improved sensitivity when both investigations were used (89.3%). Abdominal ultrasound had a lower sensitivity than both of the above investigations of 65%. Gastroduodenoscopy had a sensitivity of 90% for diagnosing duodenal tumours. Operative procedures were performed on 92 patients with a preoperative diagnosis made in 77%. Metastatic spread of malignant tumours was evident in 46%. The sites of spread were to lymph nodes (23%), liver (21%) and distant locations (2%) at diagnosis.

CONCLUSIONS

Malignant small bowel tumours are more likely to produce symptoms and signs than benign tumours, particularly caused by small bowel obstruction. Abdominal CT is the best radiological investigation for small bowel tumours and has a slight complimentary effect with SBS in improving the chances of detection. Gastroduodenoscopy remains the best investigation of duodenal tumours.

Multidetector-row computed tomography and 3-dimensional computed tomography imaging of small bowel neoplasms: current concept in diagnosis

The diagnosis of small bowel neoplasms can present a difficult challenge to the radiologist because the tumors are uncommon, often small, and may be difficult to detect radiographically. The most common small bowel neoplasms include adenocarcinoma, carcinoid, lymphoma, and gastrointestinal stromal tumors. The location and computed tomography (CT) appearance of the small bowel tumors may aid in the diagnosis. For instance, small bowel adenocarcinoma occurs more frequently in the duodenum and may result in obstruction. Carcinoid tumors are more common in the ileum and are typically hypervascular submucosal masses that produce a characteristic mesenteric mass when they spread to the mesenteric nodes. Lymphoma can occur anywhere along the gastrointestinal tract and have a variable CT appearance. It may appear as a single mass, multiple masses, an infiltrating lesion resulting in aneurysmal dilatation of the bowel, or as an exophytic mass. Gastrointestinal stromal tumors are more common in the jejunum and ileum and usually appear exophytic and bulky often with ulceration. Traditionally, small bowel series and enteroclysis have been used for imaging patients with suspected small bowel tumors. More recently, CT is beginning to play a more important role for this clinical indication. The thinner collimation possible with multidetector CT (MDCT) along with water as oral contrast and a good intravenous contrast bolus may improve the sensitivity of CT for detecting small bowel tumors. In addition, MDCT scanners improve the quality of the 3-dimensional CT (3D CT) images that are valuable to the clinicians and surgeons for surgical planning. It is important for the radiologist to be familiar with the CT appearance of these neoplasms and the potential role of MDCT and 3D imaging in their diagnosis and surgical planning.

3D modeling and virtual endoscopy of the small bowel based on magnetic resonance imaging in patients with inflammatory bowel disease

RATIONALE AND OBJECTIVES

Small bowel MRI (MR imaging) is a new imaging modality that excellently depicts small intestine pathology in patients with inflammatory bowel disease. Virtual endoscopy based on sectional imaging is a recently introduced technique to create endoscopy like views. The aim of this study was to evaluate the feasibility of virtual small bowel endoscopy based on MR imaging in patients with Crohn disease.

MATERIALS AND METHODS

Thirty consecutive patients with Crohn disease were scanned after oral application of pineapple juice for contrasting the small bowel. Dedicated high resolution T1 weighted 3D-FLASH sequences with fat suppression were used for volume scanning. Volume-rendered 3D models of the small bowel were created and virtual endoscopy was performed. The feasibility and quality of this new visualization method was assessed.

RESULTS

In nine of 30 patients virtual endoscopy was considered as good quality (flight through the entire small bowel was possible, typical folds were revealed). In 18 patients fair quality (at least 4/5 of the small bowel were depicted adequately) was assessed. In three of 30 patients virtual endoscopy was not sufficiently possible because of inadequate bowel filling or breathing artifacts. Three fistulae diagnosed on 2D MRI were visualized on the virtual endoscopic view.

CONCLUSION

Virtual endoscopy of the small bowel is feasible based on high resolution MR imaging. Vivid insight views and 3D models provide an interesting addition to sectional MR findings.

Radiologic evaluation and staging of small intestine neoplasms

The small intestine is an uncommon location for neoplasms in either clinical or radiological practice. Because of its anatomic location and morphology, diagnosis of the diseases that affect small intestine pose difficulties. Symptoms are nonspecific and endoscopy is commonly unsatisfactory. Since early and definite diagnosis is crucial for prompt therapy, radiological imaging plays an essential role. Enteroclysis is the primary and effective radiologic modality in the evaluation of small bowel neoplasms. On the other hand, computed tomography should be the complementary radiologic method as well as for staging. In this review, the most common neoplasms of the small intestine and their common radiologic findings have been discussed.

Malignant melanoma: patterns of metastasis to the small bowel, reliability of imaging studies, and clinical relevance

OBJECTIVES

The aims of this study were to determine the frequency of different patterns of melanoma metastases to small bowel on radiological examination, and to assess the reliability of the most commonly used radiological methods for detecting these lesions.

METHODS

The records of cases archived as melanoma metastatic to the small bowel of the Armed Forces Institute of Pathology were reviewed. The clinical information, type of imaging procedure performed, and radiological features were analyzed and compared to the findings at surgery and at autopsy.

RESULTS

A total of 32 patients had clinical and surgical data with pathological confirmation. Seven patients had metastasis involving the duodenum, 22 had jejunal involvement, and 11 had ileal involvement. Metastases were categorized as polypoid, cavitary, infiltrating, or exoenteric. The polypoid pattern was seen in 20 patients (63%), six of whom showed multiple polypoid lesions (>10), referred to as polyposis. The "target lesion," a discrete polypoid mass with a central ulceration, was observed in only three (9%) of the 32 patients. Eight patients (25%) demonstrated a cavitary pattern, a circumferential mass with inner marginal necrosis, and five (16%) showed an infiltrating pattern. One patient (3%) had an exoenteric lesion with a fistulous tract. The small bowel follow-through demonstrated 32 of 55 metastases (sensitivity 58%). Contrast-enhanced CT demonstrated 32 of 48 masses (sensitivity 66%). Of the six cases of malignant polyposis, none were identified using CT, and only two were diagnosed by small bowel follow-through.

CONCLUSIONS

The polypoid pattern, equally distributed between the jejunum and ileum, is the most common manifestation of metastatic melanoma to the small bowel. The target lesion was infrequently seen in this series. Small bowel follow-through and conventional CT seem to be unreliable in demonstrating melanoma metastases to the small bowel.

Utility of computed tomographic enteroclysis for the general surgeon(1)

Enteroclysis uses contrast fluid distention of the small bowel through a jejunal catheter with flouroscopic imaging to identify abnormalities. Computed tomograpic enteroclysis (CT-E) adds cross-sectional imaging to identify small bowel pathology to include masses, gastrointestinal bleeding of unknown origin, and partial obstruction. Computed tomography-enteroclysis is being used more frequently in the assessment of patients with possible small bowel pathology. This study examines the applicability of CT-E and its superiority over conventional enteroclysis.A retrospective chart review was used to examine all CT-E and enteroclysis studies performed at our institution during a 24-month period (August 1997 to August 1999). All patients that had received CT-E or enteroclysis were divided into 3 categories; group I: small bowel mass, group II: gastrointestinal bleeding, and group III: partial small bowel obstruction (pSBO). All patients included had received other radiological procedures based on the indication for examination to include esophagogastroduodenoscopy, colonoscopy, CT, abdominal x-rays, barium enema, and upper gastrointestinal with small bowel follow-through.Forty-nine studies were performed, with enteroclysis or CT-E, used in 46 patients. Median age was 62 years (M:F, 1:1). In group 1 (n = 10), no masses were noted, but all patients identified as having a mass on previous studies (n = 6) were determined not to have a mass by CT-E (n = 1) and enteroclysis (n = 5). In group II (n = 19), 1 small bowel source (jejujunal arteriovenous malformation) was identified through CT-E, and all other studies in both categories were negative/normal. In group III (n = 20), 5 pSBO were identified through CT-E that had not been previously described.Enteroclysis and CT-E are both effective at disproving the presence of small bowel masses discovered through less-specific radiological methods. In terms of gastrointestinal bleeding, CT-E is as effective as enteroclysis at identifying source of bleeding and may have an added role through its ability to better identify anatomic relationships. Computed tomography-enteroclysis was able to determine the presence of pSBO in 5 patients that previously had been undiagnosed. In conclusion, enteroclysis remains an effective radiological study for examination of the small bowel. Computed tomography-enteroclysis matches that effectiveness with the added benefit on high-resolution anatomic images that serve it well as an additional diagnostic tool for the General Surgeon in patients with difficult to diagnose small bowel pathology.

Role of conventional radiology in the diagnosis and staging of gastrointestinal tract neoplasms

Preoperative diagnosis and staging of primary gastrointestinal (GI) neoplasms are challenges for both clinicians and radiologists. Barium studies are very sensitive in disclosing primary malignancies, even at an early stage. Radiologic signs depend on the evolutional stage of the disease and its appearance on gross pathology. A neoplasm may be manifested on barium studies by a wide spectrum of findings, including mucosal abnormalities, mass presence, ulcerative lesions, submucosal infiltration, and lumen stenosis. Advanced disease can be accurately diagnosed, whereas early cancer should be differentiated from other neoplastic or inflammatory disorders by meticulous analysis of radiologic findings. The extent of GI involvement and multiplicity of the lesions can be assessed on barium studies. In the staging of GI neoplasms, barium studies are of little value. Skeletal survey by conventional radiographs and chest plain films can reveal distant metastases in a short time and with low cost, although they are not that sensitive to the detection of early or subtle lesions. The exact role of conventional radiology in the imaging workup of GI malignancies depends on local expertise and availability of other diagnostic techniques and modalities.