OBT (occult blood test), gastric barium meal, immunohistochemical examination, endoscopic ultrasound examination
Patients often have gastrointestinal bleeding, manifested as positive occult blood test in feces, and histopathological examination is the basis for diagnosis.
1. Barium meal X-ray examination: Barium meal in the upper gastrointestinal tract can detect diameters greater than2cm tumor, with clear edges, round or oval filling defects. Barium meal can suggest that the mass is located under the mucosa, but cannot distinguish between lipomas and other submucosal lesions. The shape changes of the tumor when pressed are characteristic of lipomas, but only larger tumors can show this feature. In addition to the common features of gastric submucosal tumors, gastric lipomas have unique manifestations due to the low density and softness of the fatty tissue:
(1)The defect area caused by the mass is more transparent and more distinct.
(2)Deformation: The fatty tumor is soft, and the size and shape of the defect shadow can change when pressed, and even appear intermittently during the filling phase. When the gastric wall muscle layer contracts, it can also compress the tumor. In the contraction phase, it is small and tends to be elliptical, and in the relaxation phase, it becomes larger and presents a similar circular shape.
(3Displacement: The shadow of the filling defect of the fatty tumor located in the prepyloric area is more likely to move through the pyloric canal into the bottom of the duodenal bulb and appear as a 'prolapse sign', and the pyloric canal also widens at the same time.
2. CT examination: Abdominal CT not only can understand the growth of the tumor within the wall, but also can measure its CT value, understand the tissue structure of the tumor, achieve the purpose of clear diagnosis, has certain diagnostic value, can distinguish fat from other tissues, and there are several cases reported of confirmed diagnosis by CT.
3.Diagnosis endoscópica: el examen endoscópico es un método de diagnosis bastante preciso, con una tasa de positividad alta, pero se debe prestar atención a la distinción con el tumor extragástrico, se observa un tumor con superficie lisa, amarillo u naranja, suave, la mucosa del tumor tiene menor elasticidad, no puede regresar fácilmente después de ser tirado por la pinza de biopsia, formando un signo de toldo, cuando se presiona el tumor se forma una depresión, como la esponja, la biopsia rutinaria no puede alcanzar el tumor submucoso, es necesario utilizar la biopsia profunda con coagulación eléctrica para obtener el tejido tumoral, a veces se puede ver úlceras en la superficie del tumor, cuando la parte elevada cubre la mucosa normal y se forma una úlcera, se debe hacer una diagnosis diferencial con el cáncer, menor2cm son más comunes los pancreas ectópico, carcinoides o tumores miogénicos, los tumores de grasa son muy raros, para los que son mayores que2cm, la biopsia de identificación cualitativa del tumor es difícil, Kitahara Toshihiko y otros utilizan el neodimio itrio aluminio garnet (Nd-Láser YAG o etanol causan úlceras, luego se realiza una biopsia en la profundidad de la úlcera, incluso así, aún hay casos de diagnóstico falso o omisión, por lo que el uso rutinario de la endoscopia con ultrasonido es muy necesario.
4.Ecosonografía endoscópica: puede detectar tumores de alta ecogenicidad difusos submucosos, lo que también es útil para la diagnosis.