CT EVALUATION OF GASTRIC LESIONS:

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1 CT EVALUATION OF GASTRIC LESIONS: Pictural essay Hasni Bouraoui I, Kahloun A, Jemni H, Elouni F, Moulahi H, Daadoucha A, Ben Ali A, Sriha B, Tlili Graies K Departments of Radiology, Gastro enterology, Visceral surgery Hospital SAHLOUL Department of cytology Hospital Farhat Hached SOUSSE- TUNISIE

2 Introduction Multislice scan offers new opportunity for imaging of gastrointestinal tract especially in evaluation of gastric lesions. We propose a review of various lesions of the stomach, demonstrating the role of CT in their characterization.

3 Material and Methods Several cases of gastric lesions were investigated with a 16 multidetector CT scan, either for digestive symptoms or after endoscopy and biopsy. In all cases, gastric distension was obtained with water or oral contrast agent associated to intra venous contrast injection.

4 Results and comment The lesions reported are Neoplasic carcinoma gastric linitis stromal tumors lymphoma parietal involvement by a pancreatic tumor Krukenberg tumor

5 Non neoplasic varices duplication parietal hematoma caustic gastritis, phytobezoar

6 CT pattern was characteristic of the disease in all cases save 2 cases The antral duplication has been considered as duodenal and histological exam confirmed gastric origin. The trauma was neglected by the patient and the lesion diagnosed as stromal tumor, revealed after surgery an old hematoma.

7 Adenocarcinoma in 56 years old man. CTshows focal wall thickening in the antrum with marked enhancement of the mucosal layer( )

8 Adenocarcinoma in43 years old man. CTshows generalized mural thickening with marked enhancement of the gastric wall( )

9 Adenocarcinoma in 45 years old man. The wall thickening is extended to the duodenum( ) with a gastric distension

10 AdenocarcinomaLinitis plastica in 45 years old man. CT shows diffuse wall thickening of stomach

11 Gastric Adenocarcinoma Gastric carcinomas may manifest as a focal area of mural thickening with or without ulceration, as a polypoid lesion, or as generalized mural thickening. In early gastric cancers, malignant invasion is limited to the mucosa or submucosa, regardless of the presence of lymph node metastases. Advanced cancer may manifest as large, segmental, or diffuse wall thickening with irregular lobulation and, often, ulceration. Signet-ring cell cancer usually manifests as a scirrhous tumor of the stomach that leads to obliteration of gastric folds and diffuse thickening of the gastric wall (linitis plastica)

12 Carcinoma of the gastric cardia may be difficult to ppreciate at CT because of the normal soft-tissue thickening that occurs at the gastroesophageal junction. Proper distention of the stomach helps distinguish a focal tumor from the normal gastroesophageal junction. CT makes the T and N Staging of gastric cancer, detects metastases of liver, peritonea, lungs, adrenal glands, kidneys, bones, and the follow-up after partial gastrectomy.

13 Gastric lymphoma (biopsy proved). CT shows an infiltrative Gastro duodenal lymphoma as large areas of wall thickening ( ) with enlarged lymph nodes ( ).

14 Gastric Lymphoma Most cases of lymphoma involve the antrum and body, although the entire stomach can be involved. There are four gross pathologic types of gastric lymphoma: -Infiltrative gastric lymphoma -Ulcerative gastric lymphoma -Polypoid gastric lymphoma. CT is the primary imaging modality for pretreatment evaluation of abdominal lymphoma. It may allow depiction of a stomach lesion, staging of generalized lymphoma in the abdomen and chest and follow-up of disease progression in patients undergoing therapy. The CT appearances of lymphoma and gastric carcinoma may be very similar

15 53 years old woman with adenocarcinoma of the pancreas. CT shows direct invasion of the stomach( ) by the pancreatic tumor ( ).

16 CT of ovarian metastasis from gastric carcinoma( ) Tumors are lobulated and indistinguishable from uterus ( ) Krukenberg tumor s

17 Krukenberg tumor Krukenberg tumors are metastatic ovarian neoplasms from primary lesions in the gastrointestinal tract, in particular from carcinomas. When a malignant ovarian tumor is clinically suspected, CT may be the preferred method over sonography, and the stomach should be carefully examined on CT and probably by upper gastrointes tinal series and barium enema for possible primary tumor. At the same time, when CT is performed as a preoperative evaluation of gastric carcinoma, the ovaries must be routinely included in the CT field for possible Krukenberg tumor.

18 S Gastric stomal tumor in a 72years old man with weakness. CT shows an unresectable gastric mass ( ) completely surrounding the stomach with liver metastases. S : stomach lumen

19 gastric stromal tumor in a 42-year-old woman. The mass was diagnosed with endoscopic biopsy. CT shows an endoluminal mass ( )

20 Stromal tumors Gastrointestinal stromal tumors (GIST) are currently the most common nonepithelial tumors of the gastrointestinal tract. The CT features vary greatly, depending on the size and aggressiveness of the tumor and the time of presentation during the course of the disease. Primary GIST are typically large, hypervascular, enhancing masses on contrast-enhanced CT and are often heterogeneous because of necrosis, hemorrhage, or cystic degeneration at the time of presentation.

21 Ulceration and fistulization to the gastrointestinal lumen are also common features Often, tumor vessels can be seen within the tumors. The masses usually displace adjacent organs and vessels, but direct invasion of the adjacent structures is sometimes seen with advanced disease. It can be difficult to identify the origin of the mass because of its large size and prominent extraluminal location.

22 Gastric schwannoma. CT shows a submucosal softtissue mass without ulceration( ) The tumor was biopsy proved.

23 Gastric schwannoma. Neural tumors constitute about 5% 10% of benign gastric tumors. The majority are nerve sheath tumors (neurinomas, schwannomas, or neuromas). Most nerve sheath tumors are benign, but sarcomatous changes in these lesions have occasionally been reported. Neural tumors in the stomach usually appear on CT scans as submucosal masses with or without ulceration that are indistinguishable from other mesenchymal tumors

24 A 33 year-old man presented with abdominal pain and vomiting. Fibroscopy was normal. Ultrasonography: Gastro duodenal cystic mass( ).

25 Contrast CT. the mass is close to the gastro duodenal wall without lumen communications ( ). A duodenal duplication was suspected

26 MR: Axial T2 image: The cystic lesion is independent of the pancreas. The content is in hypersignal T2 ( ). Gastric duplication was confirmed at surgery and histopathological exam: HE 400: Gastric mucosa with squamous metaplasia ( )

27 Duplications of the stomach constituted about 7% of gastrointestinal tract duplications. The majority are non communicating, spherical cysts, and, although they are found anywhere in the stomach, the greater curve is the most common site They may be adherent to the pancreas. US can provide the most definitive information, however. In addition to demonstrating the cystic nature of the mass and its anatomic location. US may reveal the inner echogenic mucosal and outer hypoechoic muscle layers that are typical of a gastrointestinal tract duplication, regardless of its location. CT and MR imaging may be used to determine the nature, size, and extent of the mass. Although rare, a stomach duplication must be included in a diagnosis rang of the adult epigastric lesions.

28 L P A 67 years old woman presented with abdominal pain and vomiting. Ultrasonography: epigastric mass( ) and ascites( ). (P: pancreas, L: liver)

29 CT shows gastric mass ( ) and a second mass between stomach and liver( ) and ascite. Stromal tumor was suspected. Note the cystic lesion of liver( ) which cosidered as cystic metastase. Hematoma was confirmed at surgery and the revaeled an abdominal trauma which neglected by the patient and a bilary cyst.

30 Gastric injury Most gastric lacerations are caused by penetrating injuries, most commonly affecting the anterior wall. Patients with such injuries generaly are taken directly to surgery and are not examined with CT. Associated thoracic trauma is seen in 41% of cases. There can be substantial delay following trauma before gastric rupture occurs (days to weeks). CT findings in gastric trauma include intramural hematoma, extraserosal hematoma, or extravasated oral contrast material or air.

31 Gastric varices in a patient with hepatic cirrhosis and portal hypertension CT shows varices of the soft tissue within the posterior and posteromedial wall of the stomach.

32 Gastric Varices Varices are commonly associated with splanchnic obstruction or portal hypertension. The presence of gastric varices without esophageal varices has classically been considered a sign of isolated splenic vein occlusion, most commonly secondary to pancreatitis or pancreatic carcinoma. At CT, gastric varices appear as well-defined clusters of rounded or tubular soft tissue attenuation within the posterior and posteromedial wall of the proximal stomach. CT may indicate the origin of the varices by demonstrating such conditions as hepatic cirrhosis, calcific pancreatitis, and pancreatic carcinoma.

33 Caustic gastritis in 26 years old woman. CT shows gastric pneumatosis( ). At surgery necoosis and perforation of stomach were noted.

34 Caustic gastritis CT has proven to be valuable adjunct to endoscopy in the evaluation of caustic gastritis. It provides information about both the gastric wall involvement such pneumatosis, abscess, necrosis and perforation. CT is specially indicated when endoscopy is not possible.

35 Bezoars 19-year-old girl with psychiatric disorder. Endoscopic view of gastric : a large yellowish bezoar in the body of the stomach. CT shows an endoluminal gastric mass with peripheral calcification( ).

36 Gastric Bezoars Bezoars are collections or concretions of indigestible foreign material that accumulate and coalesce in the gastrointestinal tract. Most bezoars reside in the stomach Trichobezoars, or hairballs, are a mass of hairs and/or decaying food material, usually found in children and young females with psychiatric disorder or mental retardation. The symptoms of gastric bezoars are usually vague and nonspecific, and may include nausea, vomiting, epigastric pain and halitosis.

37 Gastric outlet obstruction, gastrointestinal tract bleeding, perforation, peritonitis, and intestinal obstruction may also complicating factors. Diagnosis of gastric bezoars requires a high index of suspicion. There is no classical presentation based on history or physical or radiographic findings. Upper gastrointestinal endoscopy is the most sensitive diagnostic method. Barium studies, sonography, and CT are also helpful in the diagnosis.

38 Conclusion CT has proven to be valuable adjunct to endoscopy in the evaluation of gastric diseases. It provides information about both the gastric wall involvement and the extra gastric extent in disease.