Abstract / Summary
Abstract Background Uterine carcinosarcoma is a rare biphasic malignant tumor, and the subtype with heterologous osteosarcomatous differentiation is exceedingly uncommon, making preoperative diagnosis challenging. Case Presentation We report the case of a 72-year-old postmenopausal woman who presented with vaginal bleeding. Transvaginal ultrasonography revealed a hypoechoic nodule within the uterine cavity, containing irregular calcified foci and punctate blood flow signals. She subsequently underwent hysteroscopic resection of the lesion with removal of the intrauterine device. Postoperative histopathology and immunohistochemistry supported a diagnosis of uterine carcinosarcoma with heterologous osteosarcomatous differentiation. To exclude a primary bone tumor and to evaluate the extent of disease, bone scintigraphy and pelvic magnetic resonance imaging were performed, followed by definitive surgical traetment. The final pathological stage was FIGO IA. Adjuvant chemotherapy with nab-paclitaxel plus carboplatin was administered. No definite evidence of recurrence or metastasis was identified during 6 months of follow-up. Conclusions This case suggests that uterine carcinosarcoma with heterologous osteosarcomatous differentiation, although rare, should be included in the differential diagnosis in postmenopausal women with abnormal uterine bleeding when ultrasonography shows an intrauterine mass with irregular calcified foci and blood flow signals, and when hysteroscopic findings suggest a malignant lesion with osseous components. Definitive diagnosis still relies on pathological examination, whereas MRI and bone scintigraphy may assist in preoperative evaluation and differential diagnosis.