Two cases of uterine leiomyosarcoma misdiagnosed as intravenous leiomyomatosis before surgery: A case report.

RATIONALE: Intravenous leiomyomatosis (IVL) and uterine leiomyosarcoma (ULMS) share overlapping imaging features, leading to frequent preoperative misdiagnosis. Accurate differentiation is critical for appropriate surgical management.

PATIENT CONCERNS: Case 1 is a 48-year-old woman with intermittent vaginal bleeding. Case 2 is a 52-year-old woman with exertional dyspnea for 8 months.

DIAGNOSES: Preoperative computed tomography venography suggested IVL in both cases. Final pathology showed case 1 for low-grade endometrial stromal sarcoma with vascular invasion and case 2 for ULMS.

INTERVENTIONS: Case 1 under hysterectomy, bilateral salpingoo-opherectomy, ureteral replantation, tumor resection. Case 2 under resection of uterus, adnexa, right kidney, and intravascular tumor.

OUTCOMES: Both cases showed a fine postoperative condition with no severe adverse reactions.

LESSONS: Intraoperative pathology is essential for distinguishing ULMS from IVL when imaging is inconclusive.