Diagnostic interpretation of non-contrast qualitative MR imaging features for characterisation of uterine leiomyosarcoma

• Published in: British journal of radiology 2021-09, Vol.94 (1125), p.20210115-20210115
• Main Authors: Sahin, Hilal, Smith, Janette, Zawaideh, Jeries Paolo, Shakur, Amreen, Carmisciano, Luca, Caglic, Iztok, Bruining, Annemarie, Jimenez-Linan, Mercedes, Freeman, Sue, Addley, Helen
• Format: Article
• Language: English
• Subjects: Adult; Aged; Diagnosis, Differential; Evaluation Studies as Topic; Female; Female genitourinary oncology special feature: Full Paper; Humans; Image Interpretation, Computer-Assisted - methods; Leiomyosarcoma - diagnostic imaging; Magnetic Resonance Imaging - methods; Middle Aged; Reproducibility of Results; Retrospective Studies; Uterine Neoplasms - diagnostic imaging; Uterus - diagnostic imaging
• ISSN: 0007-1285; 1748-880X
• DOI: 10.1259/bjr.20210115

To assess the value of non-contrast MRI features for characterisation of uterine leiomyosarcoma (LMS) and differentiation from atypical benign leiomyomas. This study included 57 atypical leiomyomas and 16 LMS which were referred pre-operatively for management review to the specialist gynaeoncology multidisciplinary team meeting. Non-contrast MRIs were retrospectively reviewed by five independent readers (three senior, two junior) and a 5-level Likert score (1-low/5-high) was assigned to each mass for likelihood of LMS. Evaluation of qualitative and quantitative MRI features was done using uni- and multivariable regression analysis. Inter-reader reliability for the assessment of MRI features was calculated by using Cohen's κ values. In the univariate analysis, interruption of the endometrial interface and irregular tumour shape had the highest odds ratios (ORs) (64.00, < 0.001 and 12.00, = 0.002, respectively) for prediction of LMS. Likert score of the mass was significant in prediction (OR, 3.14; < 0.001) with excellent reliability between readers (ICC 0.86; 95% CI, 0.76-0.92). The post-menopausal status, interruption of endometrial interface and thickened endometrial stripe were the most predictive independent variables in multivariable estimation of the risk of leiomyosarcoma with an accuracy of 0.88 (95%CI, 0.78-0.94). At any level of expertise as a radiologist reader, the loss of the normal endometrial stripe (either thickened or not seen) in a post-menopausal patient with a myometrial mass was highly likely to be LMS. This study demonstrates the potential utility of non-contrast MRI features in characterisation of LMS over atypical leiomyomas, and therefore influence on optimal management of these cases.