Bowel cancer characteristics in patients with regional enteritis

Imaging of Bowel Lymphoma: A Pictorial Review

Intestinal lymphoma, although rare, is the second most common extra-nodal site of lymphoma, following stomach. It is usually secondary to systemic involvement and is predominantly of non-Hodgkin's subtype. In addition to the risk factors for lymphomas occurring elsewhere, certain risk factors are specific for intestinal lymphoma. These include enteropathies such as celiac disease and inflammatory bowel disease. Imaging is the cornerstone in the management of intestinal lymphoma. Contrast-enhanced computed tomography or positron emission tomography-computed tomography are the preferred modalities for diagnosis, staging, monitoring response to treatment, and for follow-up evaluation. Bowel lymphomas can have various morphological patterns on imaging; however, certain characteristic features, if present, may prove invaluable in its diagnosis. Hence, it is imperative to be acquainted with the myriad of imaging findings in bowel lymphoma and its complications which may not only help in vivo distinction from other commoner bowel lesions but alter the management accordingly.

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.

Rectal cancer in inflammatory bowel diseases: MR imaging findings

PURPOSE

To retrospectively analyze the MR imaging features of rectal cancer in patients with inflammatory bowel diseases (IBD).

MATERIALS AND METHODS

The MR imaging examinations of 13 patients with IBD-related rectal cancer were retrospectively reviewed. MR imaging included T2-weighted, diffusion-weighted (DW), and gadolinium chelate-enhanced MR imaging. MR imaging findings were analyzed and compared with endoscopic and histopathological findings.

RESULTS

Eight patients (8/13; 62%) had active IBD and five (5/13; 38%) had quiescent IBD on MR imaging. Two different tumor patterns were individualized including clearly visible soft-tissue mass (4/13; 31%) (Type 1 tumor) and marked circumferential rectal wall thickening (9/13; 69%) (Type 2 tumor). Twelve tumors (12/13; 92%) showed high signal intensity on T2-weighted MR images. All six tumors studied with DW-MR imaging (6/6; 100%) showed high signal on DW-MR imaging with restricted diffusion on apparent diffusion coefficient (ADC) map. On gadolinium chelate-enhanced MR imaging, heterogeneous enhancement was observed in one tumor (1/13; 8%), whereas 12 tumors (12/13; 92%) showed homogeneous enhancement. MR imaging showed pelvic fistula and intrapelvic abscess in association with four (4/13; 31%) and two tumors (2/13; 15%), respectively.

CONCLUSION

Our limited retrospective study demonstrates that rectal cancer in IBD patients can present as a circumferential wall thickening resembling inflammation and can occur in the absence of fistula or abscess. The use of T2-weighted and DW-MR imaging is recommended to improve rectal cancer detection in patients with long-standing IBD.

Small bowel adenocarcinoma and Crohn's disease: Any further ahead than 50 years ago?

This review of the literature on small bowel carcinoma associated with Crohn’s disease specifically addresses the incidence, risk factors, and protective factors which have been identified. It also reviews the clinical presentation, the current modalities of diagnosis, the pathology, treatment, and surveillance. Finally, the prognosis and future direction are addressed. Our experience with small bowel adenocarcinoma in Crohn’s disease is reported. Readers will be provided with a better understanding of this rare and often poorly recognized complication of Crohn’s disease.

Colorectal cancer in inflammatory bowel diseases: CT features with pathological correlation

PURPOSE

To describe CT features of inflammatory bowel disease (IBD)-related colorectal cancer and correlate the imaging findings with histopathological findings.

MATERIALS AND METHODS

CT imaging findings in 17 patients with IBD-related colorectal cancer were retrospectively evaluated. Imaging findings were correlated with surgical and histopathological findings. Univariate and multivariate analyses explored the relationships between CT and histopathological variables.

RESULTS

Two different CT patterns were individualized including clearly visible soft tissue mass (8/17; 47%) (Type 1 tumor) or stenosis with marked circumferential thickening resembling inflammation (9/17; 53%) (Type 2 tumor). At univariate analysis, thickness of tumor-free colorectal wall at CT was greater in Crohn disease (median, 13 mm) than in ulcerative colitis (median, 7 mm) (P = 0.011). Significant association was found between presence of signet ring cells and Type 2 tumor at CT (6/9, 67% P = 0.009) and colonic dilatation proximal to tumor (5/6, 83%; P = 0.035). At multivariate analysis, free-fluid effusion was the single independent CT variable predictive for the presence of signet ring cells (odds ratio = 50; 95% CI 2.56-977.02; P = 0.01).

CONCLUSION

Colorectal cancer in IBD displays two main features on CT. Type 2 tumors and free-fluid effusion correlate with presence of signet ring cells. Knowledge of these findings is critical to help suggest the diagnosis.

Small bowel adenocarcinoma in Crohn disease: CT-enterography features with pathological correlation

PURPOSE

The aim of this study was to analyze the clinical, pathological, and CT-enterography findings of small bowel adenocarcinomas in Crohn disease patients.

MATERIALS AND METHODS

Clinical, histopathological, and imaging findings were retrospectively evaluated in seven Crohn disease patients with small bowel adenocarcinoma. CT-enterography examinations were reviewed for morphologic features and location of tumor, presence of stratification, luminal stenosis, proximal dilatation, adjacent lymph nodes, and correlated with findings at histological examination.

RESULTS

The tumor was located in the terminal (n = 6) or distal (n = 1) ileum. On CT-enterography, the tumor was visible in five patients, whereas two patients had no visible tumor. Four different patterns were individualized including small bowel mass (n = 2), long stenosis with heterogeneous submucosal layer (n = 2), short and severe stenosis with proximal small bowel dilatation (n = 2), and sacculated small bowel loop with irregular and asymmetric circumferential thickening (n = 1). Stratification, fat stranding, and comb sign were present in two, two, and one patients, respectively.

CONCLUSION

Identification of a mass being clearly visible suggests strongly the presence of small bowel adenocarcinoma in Crohn disease patients but adenocarcinoma may be completely indistinguishable from benign fibrotic or acute inflammatory stricture. Knowledge of these findings is critical to help suggest the diagnosis of this rare but severe complication of Crohn disease.

Ileal adenocarcinoma in Crohn's disease: magnetic resonance enterography features

Patients with Crohn's disease are at increased risk for small bowel adenocarcinoma. We report herein two cases of Crohn's disease-related ileal adenocarcinoma, which were investigated by means of magnetic resonance (MR)-enterography. Two different patterns were observed. In one case, the tumor presented as long circumferential, asymmetric and heterogeneous thickening of the ileum with visible nodule on free induction echo stimulated acquisition images. In the other case, the malignant lesion presented as a tumor mass of the terminal ileum, extending onto the cecum, and showed restricted diffusion on diffusion-weighted MR imaging. In both cases, the tumors were diagnosed preoperatively. Histopathological analysis after surgical resection confirmed T4N1 poorly differentiated mucinous adenocarcinoma of the ileum in association with findings consistent with active in one case and inactive Crohn's disease in the other case. Our observations suggest that MR-enterography may be a useful imaging test for the detection of small bowel adenocarcinoma in patients with Crohn's disease.

Small-bowel adenocarcinoma in patient with Crohn's disease: report of a series of three cases

Patients affected with Crohn's disease (CD) have a recognized, but low relative risk of developing small-bowel adenocarcinoma (SBA). In fact, SBA develops in 2.2% of patients who have long-standing CD and it is seldom diagnosed preoperatively because of its rarity. A retrospective analysis of all cases of SBA in CD patients since 1980 was carried out in Rouen University Hospital. Three patients with known or unknown CD who presented with SBA with long-term follow-up were analysed. In our first case, the occlusive syndrome revealed SBA and CD simultaneously. Most ileal carcinomas in CD are located in strictures and are often incidentally diagnosed postoperatively, as in our three cases. Digestive surgeons and gastroenterologists must be aware that the diagnosis of SBA in CD is often made fortuitously on histological examination after surgical resection for an occlusive syndrome. Failure to detect SBA in patients with CD results in late diagnosis, with poor survival.

MDCT of small bowel tumours

Primary benign and malignant neoplasm of the small bowel are rare. Malignant tumours often present late symptoms resulting in a poor prognosis. Early detection of small bowel neoplasms is desirable but challenging for both clinicians and radiologists. Conventional double contrast enteroclysis was the method of choice in small bowel imaging but is increasingly being replaced by cross-sectional imaging methods as computed tomography (CT) and magnetic resonance imaging (MRI). Multidetector CT (MDCT) produces high-resolution cross-sectional imaging of the abdomen and the small bowel. It allows multiplanar visualisation of small bowel tumours, demonstrates signs of small bowel obstruction as well as the mural and extramural extent of small bowel malignancies. This aids planning for surgical resection. In addition, liver metastases or peritoneal seeding can be detected with CT. The best visualisation of small bowel neoplasms is achieved with CT enteroclysis or enterography and this review discusses these techniques and MDCT characteristics of small bowel tumours.

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.

Rapidly and infiltratively growing Crohn's carcinoma of the small bowel: serial radiologic findings and a review of the literature

We carried out a retrospective evaluation of serial changes in the small bowel radiographs of a patient with small bowel cancer accompanied by long-standing Crohn's disease. During the 8 months before diagnosis, marked morphological changes were noted. A solitary and irregular protrusion, and rapidly growing stricture under careful medical management of the underlying disease may indicate the development of cancer.

Crohn's disease: new imaging techniques

This chapter reviews the current state of imaging in Crohn's disease. Imaging plays an important role in the diagnosis and management of Crohn's disease. Imaging is complementary to the clinical assessment of the patient and other investigations including endoscopy. The choice of imaging modality depends on the clinical circumstances and local availability of resources and skills. Close co-operation between clinicians and radiologists is important. Barium radiology remains important. Magnetic resonance imaging (MRI) and ultrasound (US) should get special consideration because of the lack of ionizing radiation. MRI is particularly good at demonstrating the perianal complication of Crohn's disease. Computer tomography (CT) and US can be used for image-guided drainage of abscesses.

Imaging of primary small intestinal tumours by enteroclysis and CT with pathological correlation

Preoperative diagnosis of primary small intestinal neoplasms can be a challenge for both clinicians and radiologists. As a result of their infrequent occurrence, they invariably present difficult problems in diagnosis and management. These problems are reflected mainly in the delayed treatment and a very poor prognosis for such malignant tumours. Their morphological changes, however, shown in enteroclysis and CT, correlate almost perfectly with the lesions identified in the gross pathological specimens. This ability to accurately image a small intestinal neoplasm, independently of its size, anatomical localization and growing tendency, represents a major improvement in the diagnosis and management of these neoplasms. This paper, based on a large series of patients with primary small intestinal neoplasms, focuses on the recognition of their detailed radiological appearances when evaluated by enteroclysis and CT.

Pseudotumoral appearance of small bowel strictureplasty for Crohn's disease

In two patients with Crohn's disease, strictureplasties had been marked operatively by a metal clip, so that definitive location on subsequent small bowel examination was possible. Each strictureplasty presented radiologically as a short annular constriction with apparently shouldered edges and parallel lumen. Similar radiological features were found in five other patients with strictureplasties, suggesting that a pseudotumoral appearance is characteristic of strictureplasty. Attention is drawn to this finding to avoid confusion with malignancy.