Why Does Gastrointestinal Bleeding Occur in Advanced Cancer?

In advanced-stage cancer, gastric bleeding may result from ulceration.

In general, tumors in late-stage cancer are particularly large. When a tumor grows to a substantial size, its central region often experiences impaired blood supply, leading to ischemia and necrosis. Many cancer patients present with gastric bleeding and melena; minor bleeding may stop spontaneously. However, when the tumor is large, extensive central ulceration occurs, exposing and rupturing blood vessels, which can cause massive hemorrhage. Therefore, prompt medical evaluation and treatment at a hospital are essential.