MRI screening for uterine leiomyosarcoma

Background Uterine fibroids are a common benign tumor and can be symptomatic, necessitating resection. Surgical myomectomy is an effective treatment option with a risk of disseminating occult uterine leiomyosarcoma (LMS), creating a need for an effective presurgical screening protocol. Clinical collaboration with contrast‐enhanced MRI including T2 and diffusion‐weighted imaging (DWI) can be utilized as a screening exam. Purpose To review the accuracy and feasibility of an interdisciplinary prospective contrast‐enhanced MRI pelvis with DWI screening system for LMS prior to fibroid resection. Study Type Retrospective cohort study. Population In all, 1960 adult female patients aged 18–87 undergoing screening MRI pelvis prior to uterine fibroid resection. Field Strength/Sequence T1 and T2‐weighted imaging, DWI, and contrast‐enhanced images were acquired at 1.5 T and 3.0 T. Assessment Each radiologist at the time of clinical study prospectively designated a confidence level of presence of LMS in the impression, which was reviewed retrospectively. A separate retrospective evaluation of the histologically proven LMS and the false positives was performed for the presence of five MRI features of LMS including low ADC values, intermediate/high T2 signal intensity, irregular margins, hemorrhage, and necrosis. A preliminary cost‐effectiveness analysis was performed, comparing the costs of treatment of uterine fibroids with vs. without a collaborative screening protocol using MRI. Statistical Tests Sensitivity, specificity, positive predictive value, and negative predictive value were obtained from the prospective evaluations. Student's t‐tests were used to compare demographics and apparent diffusion coefficient values between LMS and false‐positive results. Results We prospectively identified LMS patients with 100% sensitivity and 97% specificity. Preliminary cost analysis demonstrated that the MR screening protocol increased life expectancy by 0.04 years at a cost of $12,937 per life‐year gained. Data Conclusion MRI is an effective and potentially economic screening test, especially with standardized reporting and coordination with clinicians. Level of Evidence: 3 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2019.