A case report of uterine adenosarcoma with sarcomatous overgrowth and pulmonary metastasis

Xiaotian Qi, Q Q Wang, Jiutao Zheng, Nana Guo, Zhichun Zhang, Hongli Li, Min Dai

Background Uterine adenosarcoma is a rare malignant tumor characterized by a biphasic pattern consisting of benign epithelial components and sarcomatous stroma. The subtype with sarcomatous overgrowth is more aggressive and poses significant challenges in clinical diagnosis and management. We report the case of a 56-year-old postmenopausal woman who presented with left inguinal stabbing pain for half a month. Transvaginal ultrasonography revealed multiple nodules in the myometrium and a cystic-solid mass in the left adnexal region (65 mm × 46 mm). The patient was initially admitted with a presumptive diagnosis of “teratoma” and “uterine fibroids.” Postoperative histopathological examination of the total hysterectomy with bilateral salpingo-oophorectomy confirmed uterine adenosarcoma with hemorrhage and focal osseous metaplasia. After eight months of routine postoperative chemotherapy, chest computed tomography (CT) demonstrated pulmonary metastases. Genetic testing of the tumor tissue did not identify any mutations or gene fusions of clinical significance. Conclusion This case highlights the complexity and diagnostic challenges of uterine adenosarcoma in clinicopathological practice. Sarcomatous overgrowth and myometrial invasion are important adverse prognostic factors. No common driver gene mutations were detected in the tumor tissue of this patient, suggesting that tumorigenesis may involve more complex epigenetic regulatory mechanisms, which warrant further investigation.