Early Stage Diagnosis Methods for Advanced Gastric Cancer

The diagnosis of advanced gastric cancer involves two key components: qualitative diagnosis and staging evaluation. Qualitative diagnosis primarily relies on endoscopic biopsy to analyze the pathological type of the tumor, which is considered the gold standard for accurate identification. Staging evaluation, on the other hand, involves a combination of imaging techniques such as CT scans, MRI, and PET-CT, along with blood serum tumor marker tests to determine the extent of cancer spread.

CT scans are widely used due to their high spatial resolution, allowing doctors to clearly visualize the tumor's relationship with surrounding blood vessels and organs. This information is crucial for planning surgical interventions and predicting patient outcomes. While CT is effective for local assessment, MRI offers superior soft tissue contrast, making it particularly useful in detecting liver metastases and determining the number of affected sites.

PET-CT plays a vital role in identifying systemic or microscopic metastases, offering advantages over traditional imaging methods like CT and MRI in detecting widespread disease. In addition to imaging, serum tumor markers such as CA19-9, CEA, and CA125 are commonly used to support the diagnostic process. Although no single tumor marker is completely specific to gastric cancer, CA19-9, CA724, and CA125 have shown clinical relevance in detection and monitoring.

CA125, in particular, is helpful in assessing peritoneal metastasis, which is a key factor in determining treatment options. Some patients may also exhibit elevated levels of alpha-fetoprotein (AFP), indicating a rare subtype known as hepatoid gastric cancer or AFP-secreting gastric cancer. This variant is associated with a poorer prognosis and requires more aggressive management strategies. Combining these diagnostic tools allows for a comprehensive evaluation of advanced gastric cancer, improving both accuracy and patient care outcomes.