Prevalence of ESR1 gene mutations in gynecologic malignancies with high-estrogen receptor expression

For patients with endometrioid endometrial, low-grade serous ovarian, and granulosa cell tumors, endocrine therapy is used in the adjuvant and recurrent setting. The presence of activating mutations in the estrogen receptor gene (ESR1) is a common mechanism of resistance to antiestrogen therapy for patients with breast cancer. We aimed to investigate the prevalence of these mutations among patients with gynecologic malignancies with high estrogen receptor expression as well as breast tumors.