Endoscopic Diagnosis of Small Bowel Tumor

Abstract

Recent technological advances, including capsule endoscopy (CE) and balloon-assisted endoscopy (BAE), have revealed that small intestinal disease is more common than previously thought. CE has advantages, including a high diagnostic yield, discomfort-free, outpatient basis, and physiological images. BAE enabled endoscopic diagnosis and treatment in the deep small bowel. Computed tomography (CT) enterography with negative oral contrast can evaluate masses, wall thickening, and narrowing of the small intestine. In addition, enhanced CT can detect abnormalities outside the gastrointestinal tract that endoscopy cannot evaluate. Each modality has its advantages and disadvantages, and a good combination of multiple modalities leads to an accurate diagnosis. As a first-line modality, three-phase enhanced CT is preferred. If CT shows a mass, stenosis, or wall thickening, a BAE should be selected. If there are no abnormal findings on CT and no obstructive symptoms, CE should be selected. If there are significant findings in the CE, determine the indication for BAE and its insertion route based on these findings. Early diagnosis of small intestinal tumors is essential for favorable outcomes. For early diagnosis, the possibility of small bowel lesions should be considered in patients with unexplained symptoms and signs after examination of the upper and lower gastrointestinal tract.

Keywords: CT enterography; balloon-assisted enteroscopy; capsule endoscopy.

Figure 1

Small bowel adenocarcinomas, which are often advanced at the time of diagnosis, and endoscopic findings often include ulceration and stenosis. (a1,a2) DBE revealed adenocarcinoma in the proximal jejunum. Endoscopic enteroclysis showed the stenosis as an apple core sign. (b1,b2) DBE revealed adenocarcinoma with ulceration. CT showed mild stenosis.

Figure 2

Gastrointestinal stromal tumor (GIST): (a1–a3) Contrast-enhanced CT revealed a well-enhanced lesion. DBE showed a submucosal tumor covered by normal mucosa. (b) In patients with bleeding symptoms, erosions, ulcers, or dilated blood vessels are seen on the surface.

Figure 3

Malignant lymphoma: (a) Follicular lymphoma is characterized by aggregations of large and small white granules. The lesions are distributed focally from the duodenum to the jejunum. (b) Rarely, it may be a form of concentric stenosis with ulceration. (c1,c2) Diffuse large B-cell lymphoma (DLBCL) often shows an ulcerated or polypoid morphology, and the biopsy should be taken from the ulcer bed rather than from the edges. CT revealed a wall-thickened intestine with a dilated lumen. DBE showed an ulcerated lesion.

Figure 4

Neuroendocrine tumor: (a) SMT-like lesion with atrophied surface villi and dilated capillaries (b) A high-grade lesion with ulcers on the surface.

Figure 5

Metastatic tumors: (a) metastatic jejunal tumor from angiosarcoma of the breast. (b) Metastatic jejunal tumor from lung cancer.

Figure 6

(a) Lipoma: Lipomas are yellowish-white submucosal tumors that are soft and deform when pressed with forceps. It is characterized by low density on CT as well as fatty tissue and high echoic lesions on ultrasound. (b) Cavernous hemangioma: Localized cavernous hemangiomas are soft, pale to dark red submucosal tumors with a smooth surface.

Figure 7

Lymphangioma: Lymphangiomas have different endoscopic appearances depending on the depth of the dilated lymphatic channels. (a) If the lesion has dilated lymphatic channels in the mucosa, it will be an elevation with white dots on the surface. (b) If the lesion is primarily in the submucosa, it will have a smooth surface and a yellowish-white to pale blue submucosal tumor without white dots.

Figure 8

(a1–a3) Inflammatory fibroid polyp (IFP): IFP is a pedunculated or sub-pedunculated lesion that may be found as a submucosal tumor, but as it grows, the mucosa is shed by mechanical stimulation and is found as a smooth, protruding lesion. A large IFP can cause intussusception. This lesion was treated by a laparoscopy-assisted partial small bowel resection. (b) Ectopic pancreas: Ectopic pancreas presents as a 10~20 mm-sized, hemispherical, or sub-pedunculated SMT-like appearance with multiple nodules covered by thin, normal mucosa reflecting the internal multifocal structure, with a slight depression on the surface.

Figure 9

Polyps in patients with Peutz–Jeghers syndrome: (a) Most polyps in patients with Peutz–Jeghers syndrome are pedunculated or sub-pedunculated polyps. (b) Some of the growing lesions are branched, bifid, or multinodular, reflecting dendritic growth of the muscularis mucosa.

Figure 10

Polyps in patients with familial adenomatous polyposis: (a) Small, flat lesions often occur from the duodenum to the jejunum. (b) A large adenoma in the proximal jejunum was detected by double-balloon enteroscopy after a long period of surveillance and treatment using only conventional upper gastrointestinal endoscopy. This lesion was treated by endoscopic submucosal dissection (ESD) using the pocket-creation method and balloon-assisted endoscopy [64].