Thecomas

Thecomas are ovarian tumors that belong to the sex cord-stromal category, consisting mainly of theca interna–like cells. They are typically estrogen-secreting, which can lead to symptoms such as abnormal uterine bleeding and endometrial hyperplasia, though they may also present as a pelvic mass or be discovered incidentally. Thecomas are considered benign in most cases, with rare malignant variants described.

Most patients are middle-aged or postmenopausal, and presentation is often related to the hormonal activity of the tumor. Hormone production may cause elevated estrogen levels and associated endometrial changes; endometrial assessment is sometimes indicated to evaluate possible hyperplasia or carcinoma arising from prolonged estrogen exposure. Imaging usually shows a unilateral ovarian mass; serum markers are not specific, but hormonal studies can support the diagnosis in the appropriate clinical context.

Grossly, the tumor is typically a solitary, solid ovarian mass. Histologically, thecomas are composed of lipid-rich theca interna–like cells arranged in sheets or fascicles, with pale eosinophilic cytoplasm due to lipid droplets. The tumor may show luteinization of stromal cells. Immunohistochemistry often reveals positivity for inhibin and calretinin, supporting a sex cord-stromal origin, with variable staining for other markers.

Management is primarily surgical, usually involving unilateral salpingo-oophorectomy or tumor excision with preservation of the uterus and contralateral adnexa when fertility is a concern. Complete resection generally yields an excellent prognosis for benign thecomas; malignant cases require oncologic management and closer follow-up. In estrogen-secreting tumors, ongoing assessment of endometrial status may be warranted after treatment.