Targeted Therapy Shows Promise in Treating HER2-Positive Endometrial Cancer

Research published in Laboratory Investigation presents findings on the heterogeneity of human epidermal growth factor receptor 2 (HER2) in endometrial cancer. The study, conducted at Emory University Hospital, aimed to evaluate HER2 heterogeneity at the protein and gene levels in nonserous endometrial carcinomas. The research revealed significant intratumoral heterogeneity in HER2 expression in serous carcinomas, with 31% of tumors classified as HER2-positive using the endometrial criteria and 42.6% by the gastric criteria.

Key Takeaways:

• Targeted therapy against HER2 has shown promising results in HER2-positive endometrial cancer, with recent limited data suggesting a significant impact on treatment response.
• The study identified heterogeneous IHC staining in 45.7% of tumors, predominantly in 2+/3+ scores, indicating variability in HER2 protein expression.
• The overall HER2-positivity rate was found to be 31% using the endometrial criteria and 42.6% by the gastric criteria, highlighting the need for refined standardized testing and reporting algorithms.
• Further studies are warranted to evaluate HER2 heterogeneity and treatment response, including the impact of variable definitions in endometrial carcinomas.
• The research was conducted in collaboration with Emory University Hospital and involved a team of researchers from the Department of Pathology and Laboratory Medicine.

Statistics:

• 31% of tumors were classified as HER2-positive using the endometrial criteria.
• 42.6% of tumors were classified as HER2-positive by the gastric criteria.
• 45.7% of tumors exhibited heterogeneous IHC staining, predominantly in 2+/3+ scores.
• The study involved a retrospective analysis of biopsies and surgical specimens from patients with available HER2 immunohistochemical and fluorescence in situ hybridization results.

Sources:

• Analysis of Human Epidermal Growth Factor Receptor 2 (HER2) Heterogeneity at the Protein and Gene Levels in Endometrial Cancer: Refining HER2 Reporting and HER2-Directed Therapies. Laboratory Investigation, 2025;105(12):104240.
• NewsRx. Research Results from Emory University Hospital Update Understanding of Endometrial Cancer [Analysis of Human Epidermal Growth Factor Receptor 2 (HER2) Heterogeneity at the Protein and Gene Levels in Endometrial Cancer: Refining HER2 Reporting ...]. OBGYN & Reproduction Week. October 20, 2025; p 817.