Gastroscopy for gastric cancer

Gastroscopy is a rapid, simple and accurate method for diagnosing gastric cancer. It is the main method for diagnosing gastric cancer and has very important clinical significance for the diagnosis, differential diagnosis and early diagnosis of gastric lesions.

1. Early gastric cancer Early gastric cancer is a cancer in which the infiltration is limited to the mucosa and submucosa, regardless of whether there is lymph node metastasis. The definition was proposed by the Japanese Endoscopy Society in 1964 and is still used today. A lesion with a diameter of less than 1 cm is called a small gastric cancer, and a lesion with a diameter of less than 0.5 cm is called a microgastric cancer. When the lesion diameter is greater than 4 cm, but the depth is limited to the mucosa or submucosa, it is called superficial extensive gastric cancer.

The types of early gastric cancer include:

(1) T-type early gastric cancer: The tumor is obviously raised, with an uneven surface, and may have bleeding spots and mucosal erosions. Most of them are pedunculated.

(2) Type ⅡA early gastric cancer: The height of the tumor is more than 0.5 mm. The tumor is slightly raised above the mucosa and has a large area and an irregular surface. It may be combined with type Ⅱc lesions, sometimes accompanied by bleeding and erosion. It is difficult to diagnose with the naked eye and often requires histopathological diagnosis.

(3) Type IIB early gastric cancer: The height of the tumor does not exceed the mucosal plane, and the boundary with the surrounding mucosa is unclear. The main changes are relatively widespread mucosal redness or paleness, and local mucosal irregularity and unevenness. It is difficult to diagnose, and sometimes multiple microscopic examinations are required.

(4) Type IIc early gastric cancer: The lesion mucosa is shallowly eroded, with white fur or redness at the bottom, and the edge of the lesion is regular.

(5) Type III early gastric cancer tumors are obviously sunken or ulcerated, with necrotic exudate often covering the base, irregular edges, and bleeding, erosion, or nodular changes. Diagnosis is relatively easy.

2. Advanced gastric cancer Advanced gastric cancer refers to lesions that invade below the muscularis propria, the serosa and the periserosa, regardless of the size of the lesion or the presence or absence of lymph node metastasis.

Advanced gastric cancer is divided into 4 types according to the Borrmann classification.

(1) Borrmann type I carcinoma: It is usually a single localized hemispherical or mushroom-shaped tumor that protrudes into the gastric cavity, with a wide base, clear outline, and a smooth surface. It may be accompanied by bleeding, erosion, and ulceration, with dirty moss attached to the surface. The color of the tumor is dark red or brownish red, which is significantly different from the color of the surrounding mucosa.

(2) Borrmann type II: Microscopically, it appears as a localized ulcer with a bank-like raised edge and clear boundaries. The base of the ulcer is irregular and covered with dirty exudate.

(3) 1130rrmann type III: Microscopically, there is ulceration on a prominently raised mass. The edge of the ulcer is raised like a star bank and gradually tilts toward the surrounding mucosa, with a clear boundary. The edge is often nodular and uneven. Some of the edges are fused with the surrounding mucosa due to cancerous infiltration, and the boundary is unclear. The local mucosa is interrupted and stiff, and gastric peristalsis disappears.

(4) 130rrmann type IV: The lesion is diffusely infiltrative, mainly in the gastric wall, and endoscopic diagnosis is difficult. Generally, multiple irregular erosions or small ulcers can be seen on the mucosal surface. In severe cases, there may be stenosis of the gastric cavity and limited expansion of the gastric wall. The disappearance of gastric peristalsis makes it difficult to observe the stomach, which can easily delay diagnosis and sometimes require multiple biopsies.