Introduction

Gastric cancer, commonly known as stomach cancer, is a significant health concern worldwide. Among its various subtypes, HER2-positive (HER2+) gastric cancer has gained particular attention due to its distinct biological behavior and treatment strategies. This article delves into the causes, symptoms, and treatment options for HER2+ gastric cancer, providing crucial insights for patients, caregivers, and healthcare professionals.

Definition

HER2+ gastric cancer is a type of stomach cancer characterized by the overexpression of the human epidermal growth factor receptor 2 (HER2) protein, which promotes aggressive tumor growth. It accounts for approximately 10-20% of gastric and gastroesophageal junction cancers. HER2+ gastric cancer tends to be more aggressive than HER2-negative forms but can be treated with targeted therapies like trastuzumab (Herceptin) in combination with chemotherapy, improving patient outcomes.

What is HER2+ Gastric Cancer?

HER2 (human epidermal growth factor receptor 2) is a protein found on the surface of some cancer cells that promotes their growth. When a gastric cancer is HER2-positive, it means that the cancer cells have an overexpression of the HER2 protein, which leads to rapid tumor progression. This subtype accounts for approximately 15-20% of all gastric cancers and has a more aggressive clinical course compared to HER2-negative cancers.

HER2+ gastric cancer is typically diagnosed through specific tests such as immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH), which help determine HER2 protein levels and gene amplification.

Causes and Risk Factors

The exact causes of HER2+ gastric cancer remain unclear, but several risk factors contribute to the development of gastric cancer in general:

Genetic Factors – A family history of gastric cancer can increase the likelihood of developing the disease.

Helicobacter pylori Infection – Chronic infection with H. pylori bacteria is a significant risk factor for gastric cancer, causing inflammation and cellular changes in the stomach lining.

Dietary Habits – Consuming a diet high in salty, smoked, or processed foods can increase gastric cancer risk.

Smoking and Alcohol Consumption – Tobacco and excessive alcohol consumption have been linked to an increased risk of gastric cancer.

Age and Gender – The risk of developing gastric cancer increases with age, and it is more common in men than women.

Previous Stomach Conditions – Conditions such as chronic gastritis, gastric ulcers, and intestinal metaplasia can contribute to cancer development.

While these factors do not specifically cause HER2+ gastric cancer, they play a role in increasing the likelihood of developing any form of gastric cancer.

Symptoms of HER2+ Gastric Cancer

Early-stage gastric cancer, including HER2+ subtypes, often presents with minimal or vague symptoms, making early detection challenging. As the disease progresses, symptoms become more noticeable and may include:

• Persistent Indigestion – Frequent heartburn or stomach discomfort.
• Loss of Appetite and Weight Loss – Unexplained weight loss is a common indicator.
• Nausea and Vomiting – In some cases, vomiting may contain blood.
• Abdominal Pain – Persistent pain in the upper abdomen.
• Difficulty Swallowing (Dysphagia) – If the tumor obstructs the esophagus.
• Fatigue and Weakness – Often a result of malnutrition and anemia.
• Blood in the Stool – Black, tarry stools may indicate internal bleeding.

If these symptoms persist for more than a few weeks, seeking medical evaluation is crucial for early diagnosis and better treatment outcomes.

Diagnosis of HER2+ Gastric Cancer

Diagnosing HER2+ gastric cancer involves several tests:

Endoscopy with Biopsy – A thin, flexible tube with a camera is inserted into the stomach to examine abnormal tissues, and a biopsy is taken for further analysis.

Immunohistochemistry (IHC) Test – This test determines the level of HER2 protein expression in tumor cells.

Fluorescence In Situ Hybridization (FISH) Test – Confirms HER2 gene amplification when IHC results are inconclusive.

CT Scans and PET Scans – These imaging tests help assess the spread of the cancer.

Blood Tests – Tumor markers such as CEA and CA 19-9 may be elevated in some cases of gastric cancer.

Treatment Options for HER2+ Gastric Cancer

Treatment for HER2+ gastric cancer varies based on disease stage and overall patient health. The primary treatment options include:

Targeted Therapy:

The introduction of HER2-targeted drugs has significantly improved outcomes for patients with HER2+ gastric cancer. The most commonly used targeted therapy is:

• Trastuzumab (Herceptin) – This monoclonal antibody specifically targets HER2 proteins and is used in combination with chemotherapy for advanced or metastatic cases.
• Other Emerging Therapies – Newer agents like pertuzumab, trastuzumab deruxtecan, and tucatinib are being studied in clinical trials for improved efficacy.

Chemotherapy:

Chemotherapy is often used alongside targeted therapy to shrink tumors and slow cancer progression. Common chemotherapy drugs include:

• Fluoropyrimidines (5-FU, Capecitabine)
• Platinum-based drugs (Cisplatin, Oxaliplatin)
• Taxanes (Paclitaxel, Docetaxel)

Surgery:

For early-stage HER2+ gastric cancer, surgical removal of the tumor may be a curative option. Procedures include:

• Gastrectomy – Partial or total removal of the stomach, depending on tumor location.
• Lymphadenectomy – Removal of affected lymph nodes to prevent cancer spread.

Radiation Therapy:

Radiation therapy may be used in conjunction with chemotherapy (chemoradiotherapy) to reduce tumor size before surgery or to alleviate symptoms in advanced stages.

Immunotherapy:

In some cases, immunotherapy drugs such as pembrolizumab (Keytruda), which enhances the body’s immune response against cancer cells, may be considered.

Prognosis and Outlook

The prognosis for HER2+ gastric cancer depends on the stage at diagnosis and treatment response. While advanced cases remain challenging to treat, HER2-targeted therapies have significantly improved survival rates and quality of life. Clinical trials continue to explore newer treatment options, offering hope for better outcomes in the future.

Growth Rate of HER2+ Gastric Cancer Market

According to Data Bridge Market Research, the HER2+ Gastric Cancer market was estimated to be worth USD 1.32 billion in 2024 and is projected to grow to USD 1.86 billion by 2032. The market is anticipated to expand at a compound annual growth rate (CAGR) of 4.44% between 2025 and 2032, mainly because to the increasing prevalence and focused therapies.

Read More: https://www.databridgemarketresearch.com/reports/global-her2-gastric-cancer-market

Conclusion

HER2+ gastric cancer is a distinct and aggressive subtype of stomach cancer that requires a specialized treatment approach. Early diagnosis, targeted therapies, and a multidisciplinary treatment plan play a crucial role in improving patient outcomes. If you or a loved one experiences persistent gastric symptoms, seeking medical advice promptly can make a significant difference in the management and prognosis of the disease. Ongoing research and clinical advancements continue to pave the way for more effective treatments, offering new hope to patients battling HER2+ gastric cancer.