her2 positive gastric cancer epidemiology forecast and analysis

Key Highlights

• Gastric cancer represents the fifth most prevalent malignant tumor, and the incidence of gastric cancer varies geographically across the globe. The highest incidence rates are observed in Eastern Asia and Eastern Europe. Japan and China have the highest rates of gastric cancer among the seven major markets and China, with around 128,400 and 357,250 cases, respectively, in 2024.
• Despite the high incidence of gastric cancer, most patients are unfortunately diagnosed at advanced stages with poor prognoses due to the absence of distinguishing clinical indicators. Notably, in Western countries such as the US, Germany, Italy, France, and the UK, a higher proportion of cases are diagnosed at late stages (Stage IV), whereas, in China, the majority of cases are diagnosed at Stage III. At the time of diagnosis, metastatic disease is present in about 35% of patients in the United States. 
• In the United States, about 15% of people with advanced gastric cancer and 30% of people with advanced GEJ cancer have HER2+ tumors. Compared to Western nations, China has a lower incidence of HER2+ status in gastric cancer, including GEJ (ranging from 7–12%). 
• The total incident cases of HER2+ gastric cancer in China were ~35,500 in 2024, followed by incidents of HER2+ gastric cancer in Japan with approximately 27,000 cases.

DelveInsight’s “HER2+ Gastric Cancer (including GEJ) –Epidemiology Forecast – 2034” report delivers an in-depth understanding of the HER2+ gastric cancer (including GEJ), historical and forecasted epidemiology in the United States, EU4 (Germany, Spain, Italy, and France) and the United Kingdom, Japan, and China.

Geography Covered

• The United States
• EU4 (Germany, France, Italy, and Spain) and the United Kingdom
• Japan
• China

Study Period: 2021-2034

HER2+ Gastric Cancer (including GEJ) Disease Understanding

HER2+ Gastric Cancer (including GEJ) Overview

Gastric cancer represents the fifth most prevalent malignant tumor and the fourth leading cause of cancer-associated mortality on a global scale.

HER2, also referred to as HER2/neu or ERBB2, is present in about 15–30% of gastric cancer (including GEJ). HER2 is encoded on chromosome 17q21 and is part of the EGFR family, which also includes EGFR/HER1, HER3, and HER4. The ligand of the tyrosine kinase receptor is still not identified. HER2 forms either homodimers or heterodimers with other members of the EGFR family receptors. HER2 homodimers can lead to ligand-independent activation in case of HER2 overexpression. In gastric cancer, ERBB2 alterations are mainly present in the CIN subtype. These aberrations mainly consist of missense mutations (74%) and, only to a lesser extent, insertions (22%) or fusions (0.7%). HER2 expression is more common in the intestinal subtype according to Lauren’s classification, as well as proximal gastric cancer or GEJ cancer, metastatic disease (especially liver metastasis), and lymph node invasion.

HER2+ Gastric Cancer (including GEJ) Diagnosis

A diagnosis of HER2+ gastric cancer is made by testing a biopsy sample from the stomach tumor using IHC to assess the level of HER2 protein expression, with a positive result typically indicated by a score of 3+ on IHC; if the IHC score is equivocal (2+), further testing with FISH is required to confirm gene amplification and definitively diagnose HER2 positivity.

Additionally, the following tests and procedures are used to diagnose gastric cancer

• Medical history and physical examination
• Laboratory testing
  • Upper endoscopy with biopsy
  • Barium swallow
  • CT scan
  • MRI with gadolinium
  • Biomarker testing
    • HER2
    • PD-L1
    • Microsatellite instability
    • Mismatch repair deficiency
    • Tumor mutational burden
    • NTRK

Further details related to country-based variations are provided in the reported

HER2+ Gastric Cancer (including GEJ) Epidemiology

The HER2+ gastric cancer (including GEJ) epidemiology chapter in the report provides historical as well as forecasted epidemiology segmented by total incident cases of gastric cancer (including GEJ), gender-specific cases of gastric cancer (including GEJ), stage-specific cases of gastric cancer (including GEJ), total incident cases of HER2+ gastric cancer (including GEJ), and total incident cases of advanced HER2+ gastric cancer (including GEJ), in the 7MM and China covering the United States, EU4 (Germany, France, Italy, and Spain), United Kingdom, Japan, and China from 2021 to 2034. 

• The total incident cases of Gastric Cancer (including GEJ) in the 7MM and China comprised approximately 585,000 cases in 2024 and are projected to increase during the forecasted period.
• The total number of incident cases of gastric cancer (including GEJ) in the 7MM and China accounted for approximately 585,000 in 2024. These cases are expected to increase by 2034.
• Although China has a low rate of HER2 status in gastric cancer (including GEJ), the country has a greater overall number of HER2+ cases (accounting for about 45% of the 7MM and China cases) because China has the highest incidence of gastric cancer. Japan came in second with about 34% of the overall population share of HER2+ gastric cancer (including GEJ).
• Among the EU4 countries and the UK, Germany reported the highest number of incident cases of HER2+ gastric cancer (including GEJ) in 2024, with approximately 3,400 cases, followed by Italy, with around 3,000 cases. In contrast, the UK recorded the lowest incident cases of HER2+ gastric cancer (including GEJ).
• In Japan, a significant portion of gastric cancer cases are diagnosed at an early stage, contributing to better overall survival rates, largely due to effective screening programs and early detection methods.
• In China, among the total diagnosed cases of gastric cancer (including GEJ) by stage, Stage III accounted for the highest number of cases, with approximately 161,700 in 2024, followed by Stage IV, with approximately 80,000 cases. 

HER2+ Gastric (including GEJ) Cancer Report Insights

• Patient population
• Country-wise epidemiology distribution 

HER2+ Gastric (including GEJ) Cancer Report Key Strengths

• Ten years forecast
• 7MM and China coverage 
• HER2+ gastric cancer (including GEJ) epidemiology segmentation

HER2+ Gastric (including GEJ) Cancer Report Assessment

• Unmet needs
• Current diagnostic practices

FAQs

• What are the disease risks, burdens, and unmet needs of HER2+ gastric cancer (including GEJ)? What will be the growth opportunities across the 7MM and China concerning the patient population with HER2+ gastric cancer (including GEJ)?
• What is the historical and forecasted HER2+ gastric cancer (including GEJ) patient pool in the US, EU4 (Germany, France, Italy, and Spain), the UK, Japan, and China?

Reasons to Buy

• Insights on patient burden/disease incidence, evolution in diagnosis, and factors contributing to the change in the epidemiology of the disease during the forecast years.
• To understand KOLs’ perspectives around the accessibility, acceptability, and compliance-related challenges of HER2+ gastric cancer (including GEJ) to overcome barriers in the future.
• Detailed insights on various factors hampering disease diagnosis and other existing diagnostic challenges.