Human epidermal growth factor receptor 2 status of breast cancer patients in Asia: Results from a large, multicountry study

Despite the lack of centralized testing to confirm the accuracy of HER2 diagnoses, the incidence of HER2-positive gastric cancer observed here was comparable to that reported in the literature. Nevertheless, rates were highly variable between countries and laboratories, which suggests a lack of HER2 testing expertise in gastric cancer. Given that the mortality rates for gastric cancer in Eastern Asia are the highest in the world, efforts should focus on improving HER2 testing expertise in the region so that patients receive the appropriate treatment early in their disease.