Gastric Cancer CT Imaging Characteristics

Gastric cancer can be classified into early and advanced stages, each with distinct CT imaging features. The detection and interpretation of these features play a crucial role in diagnosis and staging. Below is a detailed overview of the CT manifestations associated with different stages of gastric cancer.

In early gastric cancer, the lesion is typically small and confined to the mucosa or submucosa. Due to its limited size and depth, it is often difficult to detect using conventional CT imaging. In such cases, endoscopy remains the gold standard for accurate diagnosis.

On the other hand, advanced gastric cancer involves deeper layers of the gastric wall, including the submucosa and muscularis propria. CT scans often reveal localized or diffuse thickening of the gastric wall, which may appear irregular or nodular. Ulcerations are frequently observed, and the affected gastric wall may demonstrate a rigid, inflexible structure. When the tumor grows beyond the stomach, it can invade adjacent organs such as the left lobe of the liver or the pancreas.

Lymph node metastasis is another key indicator seen in advanced stages. Enlarged lymph nodes can be identified in the perigastric region, hepatogastric ligament, or even in the retroperitoneum. Additionally, distant metastases are common in later stages, with the liver being a frequent site. Multiple low-density lesions in the liver parenchyma may be visible on CT scans, indicating hepatic metastasis.

Based on CT findings, gastric cancer is typically staged into four categories:

- Stage I refers to a localized tumor confined to the gastric lumen without lymph node involvement or adjacent organ invasion.
- Stage II is characterized by gastric wall thickening of 1 cm or more.
- Stage III indicates local spread to nearby organs or structures.
- Stage IV is defined by the presence of distant metastases, such as those found in the liver or other organs.

Accurate CT staging helps guide clinical decision-making and ensures patients receive the most appropriate treatment. By identifying key imaging features, radiologists can contribute significantly to the management of gastric cancer patients.