A rare incidental finding of an occult ovarian Sertoli-Leydig cell tumor presenting with hyperestrogenism in a postmenopausal woman: Diagnostic challenges

OBJECTIVE: Ovarian Sertoli-Leydig cell tumor (SLCT) is an exceptionally rare subtype of ovarian sex cord-stromal tumor, comprising less than 0.5% of ovarian neoplasms. While SLCT typically manifests in reproductive-age women, occurring in fewer than 10% of cases either prior to menarche or postmenopausally, it often presents with androgen secretion, resulting in virilization. However, occult lesions associated with hyperestrogenism in postmenopausal women are infrequent and may be easily overlooked. CASE REPORT: We present a rare case of SLCT in a 60-year-old postmenopausal woman who experienced intermittent postmenopausal bleeding for 6 years and underwent endometrial biopsy four times, with the latest revealing atypical hyperplasia. Blood examination indicated hyperestrogenism, with an elevated estradiol level of 75.64 pg/mL. MRI demonstrated mild endometrial thickening without bilateral ovarian enlargement. Following hysterectomy and bilateral salpingo-oophorectomy, pathological examination disclosed an occult SLCT of the left ovary as an incidental finding. CONCLUSION: Preoperative diagnosis of ovarian SLCT is challenging, particularly when clinical manifestations are atypical, and the ovarian tumor is too small to be detected by imaging studies. Clinicians should maintain a high index of suspicion for this occult lesion in postmenopausal women presenting with hyperestrogenism in the absence of virilization symptoms.