Ultrasound diagnostic value and clinical analysis of 61 uterine intravenous leiomyomatosis cases.

Background: Intravenous leiomyomatosis (IVL) is a rare benign smooth muscle tumor, for which the ultrasound features and diagnostic value have rarely been reported due to its infrequent presentation. This study aimed to analyze ultrasonographic characteristics and diagnostic value of uterine IVL and explore risk factors influencing postoperative recurrence. Methods: A retrospective analysis was conducted of 61 patients who underwent surgical treatment from December 2014 to December 2023. Intraoperative or postoperative pathology confirmed uterine IVL in these patients. Clinical data and ultrasonographic features were analyzed, including IVL location, the International Federation of Gynecology and Obstetrics (FIGO) classification, shape, involved vessels, extent of involvement, internal blood flow, and ultrasound diagnostic accuracy. Cumulative recurrence rates were calculated using Kaplan-Meier method, and the survival curves for clinical factors were analyzed. Prognostic analysis of IVL recurrence was performed using Cox proportional hazard model. Results: The diagnostic accuracy of ultrasound for IVL was 55.7% (34/61). The diagnostic accuracy of ultrasound was 76.7% for para-uterine IVL (P<0.001), 76.9% for FIGO 8 category (P<0.001), 84.4% for cord-like or beaded morphology (P<0.001), 92.3% for the involvement of the iliac vessels or inferior vena cava (IVC, P=0.003), and 66.7% for abundant internal blood flow (P=0.213). During the follow-up period, IVL in 10 cases (16.4%) recurred. The cumulative recurrence rates were 10.5%, 12.8%, and 18% at 1, 2, and 3 years, respectively. Patients aged ≤46.5 years (P=0.010), with IVL involving the iliac vein or IVC (P=0.017), and undergoing myomectomy (P<0.001) had a higher recurrence rate. Univariate analysis identified age (≤46.5 years) (P=0.035), IVL involving the iliac veins or IVC (P=0.029), and myomectomy (P<0.001) as risk factors for recurrence. Multivariate analysis showed that IVL involving the iliac veins or IVC [P=0.021, hazard ratio (HR) 6.407] and myomectomy (P<0.001, HR 77.360) were independent risk factors for recurrence. Conclusions: The diagnostic accuracy of ultrasound was high for IVL located adjacent to the uterus and in FIGO 8 category, especially when it presented with cord-like or beaded morphology and involved the iliac vessels or IVC. Involvement of the iliac veins or IVC and myomectomy were independent risk factors for IVL recurrence. The risk of recurrence for IVL involving the iliac veins or IVC was 6 times higher than that confined to the uterus or para-uterine veins, and the risk of recurrence was 77 times higher for myomectomy than for hysterectomy with bilateral oophorectomy.