Type:
Educational Exhibit
Keywords:
Not applicable, Retrospective, Tissue characterisation, Neoplasia, Cancer, Education, MR, Pelvis, Oncology, Genital / Reproductive system female, Genitourinary
Authors:
E. Canniff, M. Courtney, S. A. O'Keeffe, S. Harte; Dublin/IE
DOI:
10.26044/ecr2020/C-06426
Background
Malignant ovarian germ cell tumours are rare representing 5% of all ovarian malignant neoplasms. These tumours occur mostly in young women between the ages of 10 and 30 years of age 1. The histologic types are similar to tumours developing in the male testes, with dysgerminoma, immature teratoma, yolk sac tumors, and mixed germ cell tumors accounting for 90 percent of cases and non-gestational choriocarcinomas being exceptional rare.2
Diagnosis is strongly suggested preoperatively by the presence of an adnexal mass on pelvic imaging and an elevated level of an associated tumor marker (eg, hCG, AFP). MR imaging is the method of choice in characterizing indeterminate adnexal masses.2
The diagnosis is made by histology at the time of surgical excision. This pictorial review illustrates the typical imaging characteristics of several malignant germ cell tumours alongside the histopathology findings.
A standard MR protocol fpr evaluating adnexal masses was recently published by the European Society of Urogenital Radiology
Table 1: MR protocol for the characterisation of adnexal masses.
MR protocol for evaluating adnexal masses |
· T2W Sagittal of the pelvis
· T1W and T2W sequences covering the mass in the same orthogonal plane (axial or coronal) with similar slice thickness.
· DWI Axial
· T1W pre and post contrast study
If the mass is high T1 signal, perform: Axial FSE T1W FS
If unsure whether the mass is ovarian or uterine in origin perform:
Axial plane of the ovary FSE T1W FS
Axial plane of the ovary FSE T2WI
Axial plane of the ovary 3D T1W FS
Note: Axial plane of the ovary corresponds to the parallel plan of the endometrial cavity (perfect coronal plane of the body of the uterus). |