Primary malignant diseases of the small intestine

[Radiologic Diagnosis of Gastrointestinal Bleeding]

Gastrointestinal (GI) bleeding is not a single disease but a symptom and clinical manifestation of a broad spectrum of conditions in the GI tract. According to its clinical presentation, GI bleeding can be classified into overt, occult, and obscure types. Additionally, it can be divided into upper and lower GI bleeding based on the Treitz ligament. Variable disease entities, including vascular lesions, polyps, neoplasms, inflammation such as Crohn's disease, and heterotopic pancreatic or gastric tissue, can cause GI bleeding. CT and conventional angiographies and nuclear scintigraphy are all radiologic imaging modalities that can be used to evaluate overt bleeding. For the work-up of occult GI bleeding, CT enterography (CTE) can be the first imaging modality. For CTE, an adequate bowel distention is critical for obtaining acceptable diagnostic performance as well as minimizing false positives and negatives. Meckel's scintigraphy can be complementarily useful in cases where the diagnosis of CTE is suboptimal. For the evaluation of obscured GI bleeding, various imaging modalities can be used based on clinical status and providers' preferences.

Interventional gastroenterology in oncology

Cancer is one of the foremost health problems worldwide and is among the leading causes of death in the United States. Gastrointestinal tract cancers account for almost one third of the cancer-related mortality globally, making it one of the deadliest groups of cancers. Early diagnosis and prompt management are key to preventing cancer-related morbidity and mortality. With advancements in technology and endoscopic techniques, endoscopy has become the core in diagnosis and management of gastrointestinal tract cancers. In this extensive review, the authors discuss the role endoscopy plays in early detection, diagnosis, and management of esophageal, gastric, colorectal, pancreatic, ampullary, biliary tract, and small intestinal cancers.

Malignant Gastrointestinal Neuroectodermal Tumor: A New Kid on the Block?

ABSTRACT

Also referred to as "osteoclast-rich, clear cell sarcoma-like tumor of the gastrointestinal tract (CCSLGT)," malignant gastrointestinal neuroectodermal tumor is a newly described, rare, aggressive sarcoma that commonly arises in the small bowel, stomach, and colon. Histogenesis is likely from an autonomous nervous system-related primitive cell of neural crest origin. The hallmark genetic finding of EWS-CREB1 or EWS-ATF1 fusion transcripts clinches the diagnosis. Annular constrictive lesions tend to be smaller, show homogenous contrast enhancement on computed tomography, and may present with bowel obstruction. Larger, expansile masses tend to be exophytic and show heterogeneous contrast enhancement. Surgical resection is the mainstay of treatment. Frequent recurrences, metastases, and death from disease in 75% of patients portend a poor prognosis. Targeted chemotherapy based on specific tumor pathways is being developed.

Gastrointestinal Bleeding at CT Angiography and CT Enterography: Imaging Atlas and Glossary of Terms

Gastrointestinal (GI) bleeding is a common potentially life-threatening medical condition frequently requiring multidisciplinary collaboration to reach the proper diagnosis and guide management. GI bleeding can be overt (eg, visible hemorrhage such as hematemesis, hematochezia, or melena) or occult (eg, positive fecal occult blood test or iron deficiency anemia). Upper GI bleeding, which originates proximal to the ligament of Treitz, is more common than lower GI bleeding, which arises distal to the ligament of Treitz. Small bowel bleeding accounts for 5-10% of GI bleeding cases commonly manifesting as obscure GI bleeding, where the source remains unknown after complete GI tract endoscopic and imaging evaluation. CT can aid in identifying the location and cause of bleeding and is an important complementary tool to endoscopy, nuclear medicine, and angiography in evaluating patients with GI bleeding. For radiologists, interpreting CT scans in patients with GI bleeding can be challenging owing to the large number of images and the diverse potential causes of bleeding. The purpose of this pictorial review by the Society of Abdominal Radiology GI Bleeding Disease-Focused Panel is to provide a practical resource for radiologists interpreting GI bleeding CT studies that reviews the proper GI bleeding terminology, the most common causes of GI bleeding, key patient history and risk factors, the optimal CT imaging technique, and guidelines for case interpretation and illustrates many common causes of GI bleeding. A CT reporting template is included to help generate radiology reports that can add value to patient care. An invited commentary by Al Hawary is available online. Online supplemental material is available for this article. ^©RSNA, 2021.

Kvasir-Capsule, a video capsule endoscopy dataset

Artificial intelligence (AI) is predicted to have profound effects on the future of video capsule endoscopy (VCE) technology. The potential lies in improving anomaly detection while reducing manual labour. Existing work demonstrates the promising benefits of AI-based computer-assisted diagnosis systems for VCE. They also show great potential for improvements to achieve even better results. Also, medical data is often sparse and unavailable to the research community, and qualified medical personnel rarely have time for the tedious labelling work. We present Kvasir-Capsule, a large VCE dataset collected from examinations at a Norwegian Hospital. Kvasir-Capsule consists of 117 videos which can be used to extract a total of 4,741,504 image frames. We have labelled and medically verified 47,238 frames with a bounding box around findings from 14 different classes. In addition to these labelled images, there are 4,694,266 unlabelled frames included in the dataset. The Kvasir-Capsule dataset can play a valuable role in developing better algorithms in order to reach true potential of VCE technology.

Imaging of the small bowel: a review of current practice

This article summarises radiological imaging of the small bowel, with an emphasis on Crohn's disease. Different imaging techniques are discussed, including the advantages and disadvantages of each modality, and radiological findings for common small bowel pathologies are described, supplemented with pictorial examples.

Small Bowel Neoplasms: A Pictorial Review

Small bowel tumors are rare and account for approximately 3% of all gastrointestinal tumors in the United States. The incidence of small bowel neoplasms is rising-in particular, there is a rising incidence of small bowel carcinoid tumors. This may in part be due to small bowel lesion identification in an increasing number of cross-sectional imaging studies performed for other indications as well as increased use of advanced imaging techniques to assess specifically for small bowel disease. Diagnosis is a challenge owing to nonspecific clinical manifestation, rare occurrence, and low index of clinical suspicion. Yet, various small bowel neoplasms have characteristic imaging features at CT and MRI when optimal distention of the small bowel is achieved, correlating well with features seen in gross specimens. Understanding the imaging features of small bowel neoplasms is important to improve the radiologist's ability to diagnose and characterize small bowel neoplasms. Most small bowel tumors are clinically silent for long periods, and nearly half of the benign tumors are found incidentally during surgery or at cross-sectional imaging performed for other reasons. The authors review the imaging features of common benign and malignant small bowel neoplasms to aid the radiologist in diagnosis of small bowel tumors. ^©RSNA, 2020.

A convenient clinical nomogram for predicting the cancer-specific survival of individual patients with small-intestine adenocarcinoma

Background

The objective of this study was to develop a practical nomogram for predicting the cancer-specific survival (CSS) of patients with small-intestine adenocarcinoma.

Methods

Patients diagnosed with small-intestine adenocarcinoma between 2010 and 2015 were selected for inclusion in this study from the Surveillance, Epidemiology, and End Results (SEER) database. The selected patients were randomly divided into the training and validation cohorts at a ratio of 7:3. The predictors of CSS were identified by applying both forward and backward stepwise selection methods in a Cox regression model. The performance of the nomogram was measured by the concordance index (C-index), the area under receiver operating characteristic curve (AUC), calibration plots, the net reclassification improvement (NRI), the integrated discrimination improvement (IDI), and decision-curve analysis (DCA).

Results

Multivariate Cox regression indicated that factors including age at diagnosis, sex, marital status, insurance status, histology grade, SEER stage, surgery status, T stage, and N stage were independent covariates associated with CSS. These factors were used to construct a predictive model, which was built and virtualized by a nomogram. The C-index of the constructed nomogram was 0.850. The AUC values indicated that the established nomogram displayed better discrimination performance than did the seventh edition of the American Joint Committee on Cancer TNM staging system in predicting CSS. The IDI and NRI also showed that the nomogram exhibited superior performance in both the training and validation cohorts. Furthermore, the calibrated nomogram predicted survival rates that closely corresponded to actual survival rates, while the DCA demonstrated the considerable clinical usefulness of the nomogram.

Conclusion

We have constructed a nomogram for predicting the CSS of small-intestine adenocarcinoma patients. This prognostic model may improve the ability of clinicians to predict survival in individual patients and provide them with treatment recommendations.

Magnetic Resonance of Small Bowel Tumors

Tumors of the small intestine represent less than 5% of all gastrointestinal tract neoplasms. Magnetic resonance (MR) imaging is rapidly increasing clinical acceptance to evaluate the small bowel and can be the initial imaging method to investigate small bowel diseases. MR examinations may provide the first opportunity to detect and characterize tumors of the small bowel. Intraluminal and extraluminal MR findings, combined with contrast enhancement and functional information, allow accurate diagnoses and consequently characterization of small bowel neoplasms. This article describes the MR findings of primary small bowel neoplasms and the MR findings for the differential diagnosis are discussed.

Surgical Management of Jejunal Tumors: Experience from Tertiary Care Centre

INTRODUCTION

Small bowel is an uncommon site for primary neoplasm in the gastrointestinal tract. Traditionally, duodenum has been combined with jejunum and ileum in analysing the presentation and management of these tumors. Given the different presentation pattern, diagnostic difficulties and anatomical considerations, jejunal tumors may differ from duodenal tumors.

METHODOLOGY

Retrospective analysis of a prospectively maintained database of patients with histology proven jejunal tumors was done. Clinico-radiological characters, histological findings, surgical procedures and the outcomes in these patients were studied.

RESULTS

Sixteen patients were included in the study. Median age at presentation was 42 years (26-76 years) and majority were males (n = 11, 68.8%). Seven (43.7%) patients presented with emergencies. Endoscopic tissue diagnosis could be obtained in 5 (31.3%) patients. Histology of tumors were adenocarcinoma, gastrointestinal stromal tumor and lymphoma in 6 (37.5%), 5 (31.3%) and 3 (18.8%) respectively. Sarcoma (myxofibroma) and metastasis (urothelial origin) were present in one patient each. Two patients with adenocarcinoma had neoadjuvant chemotherapy. Curative resection was feasible in 14 patients. Resection of tumor-bearing segment with anastomosis was performed in 9 patients. Among these, 5 had duodenojejunostomy. One patient had resection and double-barrel jejunostomy. One patient with jejunal GIST had sleeve resection. Multi-visceral resection was performed in 3 patients. There were no mortality and median postoperative hospital stay was 11 days (range 7-33 days).

CONCLUSION

Histology spectrum of jejunal tumors are distinct. Difficulty in obtaining preoperative tissue diagnosis of these lesions need to be addressed by improved endoscopic and image-directed biopsy techniques.

Multimodality imaging of small bowel neoplasms

Although the small intestine accounts for over 90% of the surface area of the alimentary tract, tumors of the small intestine represent less than 5% of all gastrointestinal tract neoplasms. Common small bowel tumors typically are well evaluated with cross-sectional imaging modalities such as CT and MR, but accurate identification and differentiation can be challenging. Differentiating normal bowel from abnormal tumor depends on imaging modality and the particular technique. While endoscopic evaluation is typically more sensitive for the detection of intraluminal tumors that can be reached, CT and MR, as well as select nuclear medicine studies, remain superior for evaluating extraluminal neoplasms. Understanding the imaging characteristics of typical benign and malignant small bowel tumors is critical, because of overlapping features and associated secondary complications.

Radiologic Assessment of Gastrointestinal Bleeding

Gastrointestinal (GI) bleeding represents a broad differential of disease throughout the GI tract. The proper diagnostic evaluation of patients presenting with symptoms of GI bleeding depends on the overall clinical acuity and suspected source locations. The radiologic assessment of these patients is centered around computed tomography (CT) angiography, CT enterography, conventional angiography, and nuclear scintigraphy.

Imaging Workup of Acute and Occult Lower Gastrointestinal Bleeding

Lower gastrointestinal bleeding is defined as occurring distal to the ligament of Treitz and presents as hematochezia, melena, or with anemia and positive fecal occult blood test. Imaging plays a pivotal role in the localization and treatment of lower gastrointestinal bleeds. Imaging tests in the workup of acute lower gastrointestinal bleeding include computed tomography (CT) angiography, nuclear medicine scintigraphy, and conventional catheter angiography. Catheter angiography can also be used to deliver treatment. Imaging tests in the workup of occult lower gastrointestinal bleeding include CT enterography and nuclear medicine Meckel scan.

Computed Tomography Enterography

Computed tomography (CT) enterography is a noninvasive imaging modality with superb spatial and temporal resolution, specifically tailored to evaluate the small bowel. It has several advantages over other radiologic and optical imaging modalities, all of which serve as complementary investigations to one another. This article describes CTE technique, including dose reduction techniques, special considerations for the pediatric population, common technical and interpretive pitfalls, and reviews some of the more common small bowel entities seen with CTE.

Minimally Invasive Treatment of Sporadic Burkitt's Lymphoma Causing Ileocaecal Invagination

Introduction

Primary NHL (non-Hodgkin lymphoma) of the colon represents only 0.2% to 1.2% of all colonic malignancies. Burkitt's lymphoma (BL) is usually a disease reported in children and young people, most of them associated with EBV or HIV infection. We describe a rare case of intestinal obstruction due to sporadic Burkitt's lymphoma causing ileocaecal invagination explaining our experience Methods. A 31-year-old man presented with diffuse colic pain and weight loss. Clinical examination revealed an abdominal distension with pain in the right iliac fossa. Colonoscopy documented a caecal large lesion with ulcerated mucosa. Computed tomography (CT) have shown a 60 × 50 mm right colic parietal lesion with signs of ileocolic intussusception.

Results

Laparoscopic right hemicolectomy was performed. Postoperative period was uneventful. CD20+ high-grade B-cell Burkitt's lymphoma was confirmed by immunohistochemistry (CD20+, CD79+, and CD10+) and FISH test (t (8;14) (q24; q32). The patient was subsequently treated with adjuvant combination chemotherapy (Hyper-CVAD) and is alive and disease-free at 8 months follow-up.

Discussion

Adult sporadic Burkitt's lymphoma (BL) causing intestinal obstruction due to ileocaecal intussusception is an extremely rare occurrence and a diagnostic dilemma. Despite the surgical approach is selected based on patient's conditions and surgeon's expertise, minimally invasive method could be preferred.

Clinicopathological features, surgical treatments, and survival outcomes of patients with small bowel adenocarcinoma

To date, because of their rarity, the clinicopathological features and surgical outcomes of small bowel adenocarcinomas (SBAs) have been insufficiently explored. We evaluated the clinicopathological features and long-term outcomes of patients who underwent surgery for SBA.This retrospective study (from 1999 to 2016) examined patients with SBA treated surgically at the China National Cancer Center/Cancer Hospital. Clinicopathological features, preoperative evaluation, surgical treatment, and outcome parameters were reviewed and analyzed.Among the 241 patients studied, pancreaticoduodenectomies were performed in 51.0%, partial resection in 24.5%, palliative bypass surgery in 23.7%, and abdominal exploration in 0.8% of the patients. Majority of the patients were diagnosed at an advanced disease stage, and the duodenum was the most common tumor site. Postoperative complications occurred in 44.4% of the patients. Median overall and progression-free survival rates were 22.0 and 13.0 months, respectively. The 5-year overall and progression-free survival rates for patients with duodenal adenocarcinoma were 30.2% and 21.7%, respectively. Duodenal adenocarcinomas, lymph node metastases, distant metastases, poor differentiation, and lymphovascular invasion were associated with poor overall survival outcomes. The 3 factors associated with progression-free survival were the degree of differentiation, lymph node metastases, and distant metastases.Surgery remains the mainstay of treatment for SBA. A poor prognosis could be owing to the site, metastasis, differentiation, and lymphovascular invasion; however, the prognosis may improve through early diagnosis and operation.

Small-Bowel Neoplasms: Role of MRI Enteroclysis

Small-bowel neoplasms are the 3%–6% of all gastrointestinal tract neoplasms. Due to the rarity of these lesions, the low index of clinical suspicion, and the inadequate radiologic examinations or incorrect interpretation of radiologic findings, a delay in diagnosis of 6–8 months from the first symptoms often occurs. Even if conventional enteroclysis and capsule endoscopy are the most common procedures used to accurately depict the bowel lumen and mucosal surface, their use in evaluating the mural and extramural extents of small-bowel tumors is limited. Instead multidetector computed tomographic enteroclysis and magnetic resonance enteroclysis have the potential to simultaneously depict intraluminal, mural, and extraintestinal abnormalities. In particular MR enteroclysis has an excellent soft tissue contrast resolution and multiplanar imaging capability. It can provide anatomic, functional, and real time information without the need of ionizing radiation. MR findings, appearances of the lesions, combined with the contrast-enhancement behavior and characteristic of the stenosis are important to differentiate small-bowel neoplasm from other nonneoplastic diseases.

MDCT and clinicopathological features of small bowel gastrointestinal stromal tumours in 102 patients: a single institute experience

OBJECTIVE

Small bowel (SB) is the second most common site of gastrointestinal stromal tumours (GISTs). We evaluated clinical presentation, pathology, imaging features and metastatic pattern of SB GIST.

METHODS

Imaging and clinicopathological data of 102 patients with jejunal/ileal GIST treated at Dana-Farber Cancer Institute and Brigham and Women's Hospital (Boston, MA) between 2002 and 2013 were evaluated. Imaging of treatment-naive primary tumour (41 patients) and follow-up imaging in all patients was reviewed.

RESULTS

90/102 patients were symptomatic at presentation, abdominal pain and lower gastrointestinal blood loss being the most common symptoms. On pathology, 21 GISTs were low risk, 17 were intermediate and 64 were high risk. The mean tumour size was 8.5 cm. On baseline CT (n = 41), tumours were predominantly well circumscribed, exophytic and smooth/mildly lobulated in contour. Of 41 tumours, 16 (39%) were homogeneous, whereas 25 (61%) were heterogeneous. Of the 41 tumours, cystic/necrotic areas (Hounsfield units < 20) were seen in 16 (39%) and calcifications in 9 (22%). CT demonstrated complications in 13/41 (32%) patients in the form of tumour-bowel fistula (TBF) (7/41), bowel obstruction (4/41) and intraperitoneal rupture (2/41). Amongst 102 total patients, metastases developed in 51 (50%) patients (27 at presentation), predominantly involving peritoneum (40/102) and liver (32/102). 7/8 (87%) patients having intraperitoneal rupture at presentation developed metastases. Metastases elsewhere were always associated with hepatic/peritoneal metastases. At last follow-up, 28 patients were deceased (median survival, 65 months).

CONCLUSION

SB GISTs were predominantly large, well-circumscribed, exophytic tumours with or without cystic/necrotic areas. Complications such as TBF, bowel obstruction and intraperitoneal perforation were visualized at presentation, with patients with perforation demonstrating a high risk of metastatic disease. Exophytic eccentric bowel wall involvement and lack of associated adenopathy are useful indicators to help differentiate GISTs from other SB neoplasms.

ADVANCES IN KNOWLEDGE

SB GISTs are predominantly large, well-circumscribed, exophytic tumours, and may present with complications. They often are symptomatic at presentation, are high risk on pathology and metastasize to the peritoneum more commonly than the liver.

BWH emergency radiology--surgical correlation: small-bowel GI stromal tumor perforation

We present the radiological and intraoperative correlation of a large necrotic gastrointestinal stromal tumor (GIST) with features of a tumor-bowel fistula and perforation in a 49-year-old woman presenting to the emergency department with a 4-day history of worsening abdominal pain, vomiting, and diarrhea. The patient underwent urgent exploratory laparotomy for partial resection of the small bowel, with primary anastomosis. The purpose of this article is to emphasize the importance for emergency radiologists to be familiar with this entity and its possible complications to help guide the surgeons in the patient's management.

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.