A 62-year-old woman undergoes screening upper endoscopy for chronic dyspepsia. A gastric mass is identified and biopsied. The pathologist reports gastric adenocarcinoma. Which is the most common anatomical site of gastric carcinoma in the stomach?

Explanation

## Anatomical Sites of Gastric Carcinoma **Key Point:** The pyloric antrum and lesser curvature are the most common sites of gastric carcinoma, accounting for approximately 50–60% of all gastric cancers. ### Distribution by Site | Anatomical Site | Frequency | Features | | --- | --- | --- | | **Pyloric antrum + lesser curvature** | 50–60% | Most common; associated with H. pylori | | **Fundus + greater curvature** | 20–30% | Second most common | | **Cardia + GE junction** | 10–15% | Associated with Barrett's esophagus, GERD | | **Body of stomach** | 5–10% | Least common | ### Why Antrum and Lesser Curvature? 1. **Chronic H. pylori infection**: Preferentially colonizes the antrum and lesser curvature, leading to chronic atrophic gastritis and intestinal metaplasia in these regions 2. **Acid-secreting mucosa**: The antrum is the site of gastrin-producing G cells; chronic inflammation here triggers the Correa cascade 3. **Stasis and bile reflux**: The pyloric region is prone to stasis and bile reflux, both carcinogenic factors 4. **Lymphatic drainage**: Rich lymphatic network in the lesser curvature facilitates early nodal involvement ### Clinical Correlations **High-Yield:** In India and East Asia, where H. pylori prevalence is high, antral and lesser curvature cancers predominate. These are often diagnosed at advanced stages because the antrum is less accessible to early detection. **Clinical Pearl:** Cardia and GE junction cancers are increasing in the West due to rising GERD and Barrett's esophagus. These are often adenocarcinomas of the gastroesophageal junction and may be classified as esophageal cancers depending on the epicenter of the lesion. ### Staging and Prognosis by Site - **Antral cancers**: Often present at advanced stage (T3–T4) due to late symptoms; involve regional lymph nodes early - **Cardia cancers**: May extend into the esophagus; associated with worse prognosis - **Fundal cancers**: Tend to be diagnosed later due to silent location **Mnemonic: ALFC** — **A**ntrum (most common), **L**esser curvature (most common), **F**undus (second most), **C**ardia (least common).