her2 positive gastric cancer epidemiology forecast

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 has the highest rates of gastric cancer among the seven major markets, with around 129,500 cases, 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), in contrast to that in Japan, the majority of cases are diagnosed at an early stage (Stage I). 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.
• In 2024, the total number of incident cases of HER2+ gastric cancer in the US was approximately 6,650, whereas Japan reported the highest incidence, with around 27,000 cases.

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

Geography Covered

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

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 Immunohistochemistry (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 Fluorescence In Situ Hybridization (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
  • Computed Tomography (CT) scan
  • Magnetic Resonance Imaging (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 covering the United States, EU4 (Germany, France, Italy, and Spain), United Kingdom, and Japan from 2021 to 2034. The total incident cases of gastric cancer (including GEJ) in the 7MM comprised approximately 211,560 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 accounted for approximately 211,550 in 2024. These cases are expected to increase by 2034.
• In 2024, Japan contributed to the largest incident cases of HER2+ gastric cancer, acquiring ~60% of the 7MM cases. Whereas EU4 and the UK, accounted for around 25% of the total population share, respectively, in 2024.
• 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 fewest incident cases of HER2+ gastric cancer (including GEJ).
• In the US, among gender in gastric cancer (including GEJ), males accounted for the highest number of cases, i.e., 66% in 2024.
• 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 Japan, among the total diagnosed cases of gastric cancer (including GEJ) by stage, Stage I accounted for the highest number of cases, with approximately 95,400 in 2024, followed by Stage III with approximately 12,600 cases. 

HER2+ Gastric Cancer (including GEJ) Report Insights

• Patient population
• Country-wise epidemiology distribution

HER2+ Gastric Cancer (including GEJ) Report Key Strengths

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

HER2+ Gastric Cancer (including GEJ) 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 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, and Japan?

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.