Stomach Diseases: An Overview and Key Considerations

Stomach disease is a general term referring to various conditions affecting the stomach, including:

• Gastritis: Inflammation of the stomach lining, which can be acute or chronic.
• Peptic Ulcer Disease (PUD): Deeper sores in the stomach lining, forming ulcers.
• Stomach Cancer: Abnormal cell growth in the stomach lining, developing out of control.

1. Peptic Ulcer Disease:

1.1 Classification:

• Chronic Peptic Ulcer: The most common type, characterized by recurring ulcers that heal and then reappear.
• Acute Peptic Ulcer: Develops rapidly, often triggered by specific factors like stress, medication, or certain infections. Acute exacerbations of chronic ulcers are common.

1.2 Prevalence:

• The prevalence of peptic ulcer disease in Europe and the United States is estimated to be 5-10%, while in Vietnam it ranges from 4-8%.
• Men are disproportionately affected, accounting for 4/5 of all cases (men are four times more likely than women).

1.3 Causes:

Aggressive Factors:

• Hydrochloric Acid (HCl): Directly damages the stomach lining.
• Pepsin: A digestive enzyme that breaks down proteins and is particularly active in an acidic environment.
• Helicobacter pylori (HP): A bacteria that lives in the stomach and releases substances that cause disease.

Protective Factors:

• Mucus: Protects the stomach lining from HCl and pepsin.
• Bicarbonate: Neutralizes HCl.
• Blood: Supplies oxygen and nutrients to the lining.
• Prostaglandins: Help repair damaged cells and stimulate mucus production.
• Other Factors: Hormones, genetics, etc.

1.4 Role of Helicobacter pylori:

• 85-100% of peptic ulcer patients and 70% of those with gastric ulcers test positive for HP.
• Disease Mechanism:
  • Creation of an Alkaline Environment: HP releases ammonia (NH3), creating an alkaline environment conducive to its growth, causing H+ ions to diffuse backward, hindering mucus synthesis by cells. This disrupts mucus quality and distribution.
  • Adhesion to the Lining: HP secretes adhesins that help it bind firmly to the stomach lining cells.
  • Toxin Secretion: HP releases a cytotoxin that destroys gland cells in the lining, reducing mucus production.

1.5 Family History:

• 60% of peptic ulcer cases have a family history component.
• These individuals have 1.5-2 times more cells in their stomach lining, and their blood type is often O (1.4 times more common than other blood types).

1.6 Clinical Features:

• Chronic ulcers are more common in the duodenum than the stomach (ratio of 3:1), with most duodenal ulcers occurring at the first part of the duodenum. The anterior wall of the duodenum is more prone to ulceration than the posterior wall.
• 10-20% of patients have both gastric and duodenal ulcers.
• Lesions less than 0.3cm are often shallow erosions, while those larger than 0.6cm are definite ulcers. Approximately 90% of peptic ulcers are around 2cm in diameter, with around 10% of benign ulcers exceeding 4cm.
• The base of an ulcer has four layers: necrotic layer – fibrinoid layer – granulation layer – fibrous layer.

1.7 Diagnosis:

• X-rays, ultrasound, and endoscopy can detect 98% of peptic ulcers.

2. Stomach Cancer:

2.1 Classification:

• Gastric Adenocarcinoma: Accounts for 90-96% of stomach cancers.
• Lymphoma: Accounts for 4%.
• Carcinoid: Accounts for 3%.

2.2 Prevalence:

• Stomach cancer accounts for approximately 10% of all cancers and 50-70% of digestive cancers.
• In Vietnam, stomach cancer ranks second for men after lung cancer and third for women after breast cancer and cervical cancer.

2.3 Causes:

• Chronic Gastritis: Patients with chronic atrophic gastritis in the antrum have an 18-fold increased risk of stomach cancer. Chronic atrophic gastritis in the body of the stomach and severe pernicious anemia have a three-fold higher risk.
• Smoking: Heavy smokers have a 2-6 times higher risk of stomach cancer than non-smokers.
• Chronic Peptic Ulcer Disease: Long-standing chronic peptic ulcers, particularly in the lesser curvature and those with scarring, have a 7-10% malignant transformation rate.
• Gastric Surgery: The risk of cancer in the gastric stump varies from 1-16%.
• Gastric Polyps: Gastric adenomatous polyps have a 30% risk of malignant transformation.
• Family History: Only 4% of stomach cancer patients have a family history of the disease.
• Blood Type: Individuals with blood type A have a higher risk of stomach cancer than other groups.

2.4 Location of Cancer:

• Stomach cancer most commonly occurs in the antrum-pylorus region (50-60%), followed by the lesser curvature (20-30%), cardia (10-20%), the greater curvature (0.5%), and the fundus, anterior wall, and posterior wall (less common).

2.5 Cancer Type:

• Multifocal Stomach Cancer: Occurs in 1-8% of cases.

2.6 Cancer Stage:

Early Stage:

• Tumor size under 3cm, limited to the mucosa or submucosa but not invading the muscular layer. No metastasis, though some rare cases have shown early metastasis.
• Type 1 (Protruding, 20%): The tumor protrudes into the stomach lining, forming a polyp, nodule, or villous projection, found in 20% of cases.
• Type 2a (Flat, Protruding): The tumor grows in the mucosa, forming a small patch slightly raised with clear borders, slightly higher than the surrounding mucosa.
• Type 2b (Flat, Smooth): The tumor grows in the mucosa, forming a small, slightly firm patch, relatively flat compared to the surrounding normal mucosa.
• Type 2c (Flat, Depressed): The tumor grows in the mucosa, forming a small patch slightly depressed compared to the surrounding mucosa.
• Type 2c is the most common, representing 30-50% of cases.
• Type 3 (Ulcerative): Shows relatively clear ulceration depth, occurring in about 20-40% of cases.

Late Stage:

• Large tumors that invade the muscular layer of the stomach, possibly reaching the serosa, invading nearby organs, and metastasizing.
• Ulcerative Form: Most common, representing more than 50% of cases.

2.7 Treatment:

• Early Stage: Surgical treatment, with a 90-95% five-year survival rate.
• Late Stage: Surgical treatment combined with chemotherapy and radiation therapy, with a <10% five-year survival rate.

Note:

• This is a general overview of stomach diseases and should not replace professional medical advice.
• Stomach diseases can cause various unpleasant symptoms, even becoming life-threatening if left untreated.
• Consult a doctor for an accurate diagnosis and appropriate treatment.
• A healthy diet and lifestyle are crucial for preventing and managing stomach diseases.