Various sonographic patterns of smooth muscle tumors of the gastrointestinal tract: a comparison with computed tomography

Basic practices for gastrointestinal ultrasound

The standard diagnostic modalities for gastrointestinal (GI) diseases have long been endoscopy and barium enema. Recently, trans-sectional imaging modalities, such as computed tomography and magnetic resonance imaging, have become increasingly utilized in daily practice. In transabdominal ultrasonography (US), the bowel sometimes interferes with the observation of abdominal organs. Additionally, the thin intestinal walls and internal gas can make structures difficult to identify. However, under optimal US equipment settings, with identification of the sonoanatomy and knowledge of the US findings of GI diseases, US can be used effectively to diagnose GI disorders. Thus, the efficacy of GIUS has been gradually recognized, and GIUS guidelines have been published by the World Federation for Ultrasound in Medicine and Biology and the European Federation of Societies for Ultrasound in Medicine and Biology. Following a systematic scanning method according to the sonoanatomy and precisely estimating the layered wall structures by employing color Doppler make diagnosing disease and evaluating the degree of inflammation possible. This review describes current GIUS practices from an equipment perspective, a procedure for systematic scanning, typical findings of the normal GI tract, and 10 diagnostic items in an attempt to help medical practitioners effectively perform GIUS and promote the use of GIUS globally.

Case Report: Giant Multiloculated Pseudocystic Jejunal Leiomyosarcoma in a Dog: Atypical Morphologic Features of Canine Intestinal Leiomyosarcoma

A 10-year-old intact female Rottweiler dog weighing 29 kg presented with 2 days history of vomiting, anorexia, and lethargy to KonKuk University Teaching Hospital, Seoul, South Korea. Ultrasonography and computed tomography (CT) scannings revealed a well-demarcated, large mass (29 × 19 × 11 cm) with numerous fluid-filled cavities. Metastases to adjacent lymph nodes were also identified on CT. This large mass and the affected intestinal segments were excised for palliative purposes. Postoperatively, the dog recovered uneventfully without any complications. The cut surface of the mass showed an exophytic growth pattern of multiloculated cystic lesions filled with serosanguineous fluid, large cavities filled with necrotic exudate, and fistulous connections between the intestinal lumen and the necrotic cavity in the mass. On histopathology, the mass was a spindle cell neoplasm expanding from the jejunal muscular layer and with pseudocystic changes. Additional immunohistochemical analysis using antibodies against smooth muscle actin, desmin, and CD-117 demonstrated that the mass was consistent with a leiomyosarcoma. Six months post-operatively, plain radiography revealed an abdominal mass, suspected to be recurrence from jejunal leiomyosarcoma. The owner decided to euthanize the dog due to financial constraints. This case report describes the atypical morphology and clinical progression of a large canine jejunal leiomyosarcoma, which had similar clinical features as those of human leiomyoma and leiomyosarcoma.

Demonstration of gastric submucosal lesions by high-resolution transabdominal sonography

PURPOSE

We evaluated the accuracy of high-resolution transabdominal sonography (TAUS) in identifying and characterizing gastric submucosal masses previously detected by endoscopy.

METHODS

Patients given endoscopy for suspected submucosal gastric lesions and 2 patients with gastric wall cysts were enrolled. Patients underwent TAUS and then endoscopic sonography (EUS) on the same day, and the sonographic results were compared with endoscopic and histologic findings.

RESULTS

Among 101 patients with gastric submucosal masses on endoscopy, TAUS revealed a mass in 94 (93%); of these 94 patients, 60 underwent EUS. The final diagnoses were 31 leiomyomas, 10 leiomyosarcomas, 13 ectopic pancreases, 2 cysts, and 1 glomus tumor, 1 carcinoid tumor, 1 lipoma, and 1 fibroma. Leiomyomas (mean size, 3.2 cm) and leiomyosarcomas (mean size, 7.1 cm) were shown sonographically to originate from the muscular layer. Ectopic pancreases (mean size, 1.2 cm) were shown to originate from the submucosal layer and had a homogeneously echogenic pattern. Gastric cysts were found in the submucosal layer and were anechoic. The glomus tumor and the carcinoid tumor were found in the muscular layer and were hypoechoic. The lipoma and the fibroma were located in the submucosal layer and were echogenic on TAUS.

CONCLUSIONS

TAUS had a detection rate of 93% in visualizing submucosal gastric masses previously identified by endoscopy. TAUS is less invasive than EUS and can be used to follow submucosal gastric masses that are not excised.

Characterization of gastrointestinal tumors

Transabdominal ultrasonography is used increasingly for the evaluation of gastrointestinal disorders in small animals, including neoplasms such as lymphosarcoma, carcinoma, and smooth muscle tumors (leiomyoma, leiomyosarcoma). An updated summary of the clinical studies currently investigating the use of ultrasonography to detect and to characterize gastrointestinal neoplasia is presented in this article.