OC05.06: Clinical and ultrasound characteristics of ovarian cancers arising from mature cystic teratoma

The aim of the study is to describe the clinical and ultrasound features of malignant tumours arising from mature cystic teratoma (MCT), a rare condition. This was a retrospective multicentre study of patients with a histologically confirmed malignancy arising from MCT. Gray-scale and colour Doppler images were retrieved from 22 patients examined between 2015 and 2023. All lesions were described using the terms of the International Ovarian Tumor Analysis (IOTA) group. Clinical data were also collected. Squamous cell carcinoma was detected in 11 (50%) tumours, carcinoid tumours in 6 (27.3%),and mucinous adenocarcinomas in 5 (22.7%) tumours. All lesions were unilateral. The median largest diameter was 110mm (range 21-310mm). 8 tumours (36.4%) were classified as unilocular cysts with mixed content; 4 lesions (18.2%) were classified as multilocular tumours with “low-level” (2/4), or mixed (2/4) content; 6 tumours (27.3%) were described as unilocular-solid tumours with mixed content; two tumours (9.1%) were described as multilocular-solid tumours, with “low-level” and mixed content respectively; two lesions were purely solid. All solid components were described with inhomogeneous ecostructure. Colour Doppler examination predominantly showed a moderate vascularization (40.9%). This is the first study describing the ultrasonographic appearance of cancers arising from MCT. Most are large unilateral adnexal masses, cystic with a solid component or purely solid, moderately vascularised, with a heterogeneous echogenicity of the solid component. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.