Prognostic Significance of HER2 Positivity in Endometrium Cancer

Introduction: Endometrium cancer is the most common gynecological malignancy in developed countries. In this study, we aimed to investigate the effect of HER2 positivity on prognosis in endometrial cancer.

Methods: In our study, patients admitted to our clinic with a diagnosis of endometrial cancer between September 2019 and December 2023 were retrospectively evaluated. Human epidermal growth factor receptor 2 (HER2) immunohistochemistry was performed in 121 patients. HER2-low group (HER2 score: 0 and 1) and HER2-high group (HER2 score: 2 and 3) were defined according to the HER2 immunohistochemistry score in the pathology, and patients were compared accordingly.

Results: We observed that 97 (80.2%) of the patients were in the HER2-low group, while 24 (19.8%) were in the HER2-high group. In the OS analysis, age (p = 0.381), menopausal status (p = 0.511), ECOG performance status (p = 0.087), histological type of tumor (p = 0.727), pathological grade (p = 0.206), serum LDH (p = 0.091), and albumin (p = 0.315) levels did not affect the prognosis. Patients with lower FIGO stage (p = 0.003) and HER2-high patients (p = 0.040) had better survival outcomes. Multivariable analysis showed that FIGO stage (p = 0.004) and HER2 status (p = 0.040) were independent risk factors affecting survival in endometrial cancer.

Conclusion: As a result of our study, it was observed that FIGO stage and HER2 status were independent risk factors affecting OS in endometrial cancer patients. HER2-high group had a better prognosis than HER2-low group.