Gastric Cancer: A Review

Area of Science:

• Oncology
• Gastroenterology

Background:

• Gastric cancer is a significant global health concern, with millions of new cases and hundreds of thousands of deaths reported annually.
• The majority of gastric cancers are adenocarcinomas, predominantly affecting the stomach body or antrum, and are more common in men, with a median age at diagnosis of 68 years.

Purpose of the Study:

• To summarize the current understanding of gastric cancer epidemiology, risk factors, diagnosis, and treatment strategies.
• To highlight advancements in treatment for advanced or metastatic gastric cancer, including the role of immunotherapy and targeted therapies.

Main Methods:

• Review of epidemiological data on gastric cancer incidence and mortality.
• Analysis of diagnostic methods, including endoscopic biopsy.
• Evaluation of treatment outcomes for localized, locally advanced, and metastatic gastric cancer based on current clinical practices and emerging therapies.

Main Results:

• Gastric cancer diagnosis often occurs at advanced stages (locally advanced or metastatic) in the US, with less than 10% of metastatic cases surviving beyond 5 years.
• Helicobacter pylori infection, smoking, alcohol, obesity, and salt intake are key modifiable risk factors.
• Localized gastric cancer treated with surgery has a 5-year survival rate of 75%.
• Advanced gastric cancer treatments involving perioperative chemotherapy, immunotherapy (e.g., durvalumab), and targeted therapies (e.g., trastuzumab for ERBB2-overexpressing cancers, zolbetuximab for CLDN18.2-overexpressing cancers) improve survival by several months.

Conclusions:

• Early diagnosis through screening in high-incidence countries improves survival.
• Multimodal treatment approaches, including surgery, chemotherapy, immunotherapy, and targeted therapy, are crucial for managing gastric cancer at different stages.
• Emerging targeted therapies and immunotherapies offer survival benefits for patients with advanced or unresectable gastric cancer, particularly when guided by specific biomarkers.