Ovarian Masses: role of MRI in the differential diagnosis. A systematic approach.

Transcription

1 Ovarian Masses: role of MRI in the differential diagnosis. A systematic approach. Poster No.: C-0597 Congress: ECR 2017 Type: Educational Exhibit Authors: I. Mussetto, F. Rosa, J. Matos, G. Ficarra, D. Schettini, D Morcaldi, T. Ragusa, N. GANDOLFO ; GENOA/IT, Genova/IT Keywords: Genital / Reproductive system female, Oncology, Pelvis, MR, MR-Diffusion/Perfusion, Ultrasound-Spectral Doppler, Education, Neoplasia, Cancer, Cysts DOI: /ecr2017/C-0597 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 23

2 Learning objectives Describe a MRI guided approach to differential diagnosis of ovarian mass based on morphological appearance. Discuss the value of MR imaging in differentiation between benign and malignant ovarian mass. Review the key characteristics helpful in the diagnosis of certain ovarian tumors. Page 2 of 23

3 Background Finding an ovarian mass is common in everyday practice. While the majority of ovarian masses are found using ultrasound, MRI can provide additional specificity for adnexal masses that are indeterminate on US. For instance, fat and haemorrhage are both hyperintense on T1-weighted images, but fat-suppressed T1-weighted imaging can distinguish between lesions containing fat (such as a mature cystic teratoma) and containing haemorrhage (such as an endometrioma). Though the achievement of a diagnosis leading to a specific histological subtype is almost always impossible using MRI, it can diagnose a malignant mass with greater specificity than US or CT. The adequate distinction of a benign from a malignant mass can be done using MRI [3]. This is of great importance due to the fact that biopsy of an ovarian neoplasm cannot be done in most cases. Page 3 of 23

4 Findings and procedure details We will discuss ovarian masses based on their morphologic appearance (cystic, mixed or solid) listing the possible histological and their common RM features [1,2,5]. Note that the majority of the tumours belong to more than one morphologic type. You can review the ovarian tumours classification by histological subtype in (table 1) [4]. It is important to have in mind that approximately 90% of malignant tumours are of epithelial origin. Serous are the most common subtype followed by mucinous, endometrioid and clear cell. Unfortunately, most patients present with disseminated disease. Malignant germ-cell tumours occur in younger patients and include dysgerminoma, endodermal sinus tumour and immature teratoma. MRI technique: 1-1,5 T. We recommend administering an antiperistaltic drug intramuscularly or intravenously before the examination. T2w TSE in sagital and axial and coronal planes T1w TSE in axial plane T1w and T2w axial with a selective chemical fat-suppression technique T1w FFE in\out phase DWI 3D GRE- T1W FT 3D GRE- T1W FT dynamics - after paramagnetic intravenous contrast Benign vs malignant mass [5]: contrast-enhanced study is essential An unilocular/simple cyst is a benign mass. A malignant mass is highly suspected when primary or ancillary criteria are present (Fig.1)(table 2) [6]. When used, the sensitivity for classifying as malignancy is % and specificity is 91-92%[7]. A cystic and solid mass is malignant unless it is a mature teratoma. If a mass is not an unilocular cyst or does not have primary or ancillary criteria for malignancy, nothing can be said about the benignity or malignancy of the mass (Fig.2). Page 4 of 23

5 Differential diagnosis by morphologic appearance [1,2]: 1. Unilocular cyst (table 3) 1.1 Functional cyst: women of reproductive age or up to 5 years after menopause generally regress after 2-3 months, so that if still present in 2-3 month followup can be excluded size: from 3 to 8 cm may bleed--> classic presentation of acute abominal pain, however can be asymptomatic. Pitfall: haemorrhage automatically includes endometrioma in the differential diagnosis Graaf folicle Corpus luteum cyst 1.2 Paraovaric cyst: Located in the mesosalpinx between the ovary and fallopian tube Pitfall: may seem adnexal cysts if the ovarian stroma extends into the paraovarian cyst 1.3 Hydrosalpinx (Fig. 3): Previous history of salpingitis (PID) or pelvic endometriosis C or S-shaped tubular structure 1.4 Serous cystadenoma : Most commonly bilateral Lining of the cyst may be flat or may contain small papillary projections 2. Multilocular cyst (table 4) 2.1 Endometrioma (Fig.4): Haemorrhagic, so high signal intensity on T1w images that does not suppress after fat-supressed sequences (versus fat in teratoma); on T2w images it is typically hypointense (due to deoxyhemoglobin and methamoglobin) called "shading sign" T2 "dark spot sign" is specific for chronic haemorrhage Page 5 of 23

6 Persistence after haemorrhagic cyst 6 months confirms endometrioma and excludes 2.2. Mucinous cystadenoma (Fig.5-Fig.6): Most commonly unilateral (vs serous cystadenoma) Contains fluid of various viscosity, due to this reason the loculi of the tumours often show variable signal intensity on both T1 and T2 sequences "stainedglass appearance" 2.3 Borderline mucinous cystic tumours: Impossible to distinguish from mucinous cystadenoma preoperatively 2.4 Serous cystadenoma (less common) (Fig. 7) 2.5 Granulosa cell tumours: 95% adult-type and most commonly occur in postmenopausal women The most common malignant estrogenic tumour, so associated uterine enlargement with endometrial hyperplasia may be demonstrated on T2weighted images. 2.6 Purely cystic atypical mature teratoma 3. Mixed (solid + cystic) mass (table 5): A mixed mass strongly suggests malignancy, the notable exception is the mature cystic teratoma 3.1 Epithelial tumours: 3.1.1Serous cystadenocarcinoma (Fig.8-Fig.9): th th Peak prevalence 6-7 decades CA-125 elevated in about 90% of patients Frequent, but not necessary associated findings: papillary projections, psammomatous calcification, bilaterality, carcinomatosis Mucinous cystadenocarcinoma: Variable fluid intensity on both T1 and T2 Frequent, but not necessary associated findings: linear calcifications, carcinomatosis presents as pseudomyxoma peritonei Pitfall: may mimic metastasis to the ovary from intestinal carcinoma Page 6 of 23

7 3.1.3 Endometroid tumour: There may be associated endometrial thickening, evidence of endometriosis or contralateral mass Malignant Brenner tumour Borderline tomours (Fig.10) 3.2 Germ-cell tumours: Mature teratoma (Fig.11): Arise in young women (age years) Presence of fat is highly specific (use fat-suppressed sequences se to distinguish from endometrioma) Cystic component in most cases is unilocular Associated findings include: areas of low-signal intensity (teeth), soft-tissue protuberances, floating debris, calcifications limited to the mural nodules (vs immature teratoma) May complicate with torsion, rupture (leading to granulomatous peritonitis) and malignant degeneration Immature teratoma is extremely rare and may be differentiated from mature due to the presence of haemorrhage, necrosis, scattered calcifications and perforation of the capsule Endodermal sinus tumous 3.3 Granulosa cell tumour 3.4 Metastatic disease: Most commonly bilateral Most commonly from stomach, colon, breast, lung and contralateral ovary Mucinous lesions more frequently metastatic disease than primitive mucinous 4 Solid mass: (table 6) Include benign, malignant and borderline masses. 4.1 Epithelial ovarian carcinoma Most commonly serous cystadenocarcinoma 4.2 Metastatic disease Page 7 of 23

8 Most commonly Krukenberg tumour 4.3 Granulosa cell tumour 4.4 Dysgerminoma: Are lobulated and have a fibrous capsule Septa show strong contrast-enhancement 4.5 Fibroma, fibrotechoma (Fig. 12) and techoma: Belong to the same histologic spectrum Differential diagnosis with non-degenerated subserosal uterine leiomyomas, flow-void sign indicates leiomyoma (present in 85% of the leiomyomas with more than 7cm) 4.6 Brenner tumours: Almost always benign The abundant fibrous content and calcification in the tumor result in extensive low-signal intensity o T2-weighted images (lower than other solid tumours) 4. 7 Mature teratoma Page 8 of 23

9 Images for this section: Table 1: Classification of Ovarian Tumours [4] Page 9 of 23

10 Table 2: Table 2 Benign vs malignant Fig. 1: Fig. 1 Peritoneal implants and ascites: features tha suggest malignat mass a) axial T1w image and b) axial contrast enhancement FS T1w image show peritoneal implants (white arrows) with marked enhancement. c) and d) T2w images show ascites (white arrows). Page 10 of 23

11 Fig. 2: Fig. 2 Cystic endometriosis a 26 yo woman. a,b) axial and coronal T2w images show a large multilocular cyst mass (13x11x16 cm) with several septation (white arrowhead). c) axial STIR image. On d) sagittal FS T1w image, the cyst component show haemorrhagic hyperintensity signal (white arrow). This lesion was initially thought to be malignant but proved to be benign Table 3: Unilocular cyst [1] Page 11 of 23

12 Fig. 3: Hidrosalpinx in a 49 yo woman a, b and c) axial, sagittal and coronal T2w images show dilated right fallopian tube with hyperintense fluid signal. Multiplanar visualization demostrates S-shape tubular structure (white arrow). d) coronal contrast-enhancement FS T1w image, low signal intensity and no c.e. Table 4: Multilocular Cyst [1] Page 12 of 23

13 Fig. 4: Bilateral Endometrioma in 36 yo woman. a) T2w axial image shows a multilocular cyst with low signal intensity "shading sing" (white arrow). On b) T1w axial image shows hyperintense haemorrhagic content (white arrow). On c) and d) fat-suppressed images T1w the endometrioma remain bright; no fat component. Page 13 of 23

14 Fig. 5: Mucinous cystoadenoma in a 29 yo woman. a,b and c) axial and coronal T2w images show a large multilocular cyst mass (13x11x16 cm) with several septa (black arrowhead). Some of the tumour's loculi show lower signal intensity (white arrows) based on different mucin concentrations (stained glass appearance). d and e) contrastenhanced FS T1 W images show poor enhancement of the cystic wall and septa. f) T1w image. Fig. 6: Mucinous cystoadenoma in a 62 yo women a and c) axial T1w image show large cyst (24x22x5 cm) with intermediate signal intensity and a small septum (white arrows). b) sagittal T2w images show low-intermediate signal. d) axial T1 SPIR images show the cyst lesion with homogeneous high-intermediate signal intensity, mucinous component. f) axial contrast-enhancement T2w shows no enhancement of the tumor wall and septum. Page 14 of 23

15 Fig. 7: Serous cystadenoma in a 78 yo woman a, b and c) axial and sagittal T2w images show large multilocular cyst (atypical) with high signal intensity and thin septa (black arrowes). On d) axial T1w image, the lesion shows low signal. On e) axial contrastenhancement FS T1w image, the cyst wall and septa show poor c.e. without vegetation, nodularity or solid components. Page 15 of 23

16 Table 5: Mixed lesions [1] Page 16 of 23

17 Fig. 8: Bilateral Serous papillary cystadenocarcioma in a 72 yo woman. a and d) sagittal and coronal T2w images show large (10x13x16 cm) mixed mass with low signal intensity of the solid component; fluid in Douglas pouch (white arrows). b) sagittal T1w image. c and e) sagittal and axial contrast-enhanced FS T1w images demostrated marked enhncement of the solid component. f) DWI image show increased signal of the solid component. Page 17 of 23

18 Fig. 9: Serous cystadenocarcioma of the right ovary in a 56 yo woman. a,c) axial and coronal T2w images show a predominantly cystic lesion (*) with a posterior solid componet (arrowhead). b) axial DWI demostrated increased signal of the solid componet (arrowhead) of the lesion indicating hypercellularity. d) axial contrast-enhanced FS T1w image shows c.e. of the solid component Page 18 of 23

19 Fig. 10: Bordeline cystoadenoma in 28 yo woman. a) sagittal T2w image shows a large mass with mixed solid and multilocular cystic mass (10x13x16cm). b,d) axial contrastenhanced FS T1w images show enhancement of parietal solid component (white arrows) c) left ovary (white arrowhead). Fig. 11: Mature cystic teratoma of left ovary in a 25 yo woman. a) Sagittal T2w image and c) axial FS T2w image show well difined lesion with some fat foci inside (black arrow). b,d) axial T2w images: calcific componet (black arrow). Page 19 of 23

20 Table 6: Solid Masses [1] Fig. 12: Fibrothecoma in 39 yo woman. a, b and c) sagittal, coronal and axial T2w images show a solid mass with predominantly low signal intensity (white arrowes) and scattered high signal areas. d) axial T1w image shows the fibrothecoma with homogeneous low signal intensity. e) contrast-enhancement FS T1w image(white Arrow) Page 20 of 23

21 Conclusion Gadolinium-enhanced MR is helpful for differentiating ovarian lesions. Morphologic appearance, signal intensity characteristics, contrast enhancement provide information for arriving to a correct diagnosis. Page 21 of 23

22 Personal information Ilaria Mussetto Specializzazione in Radiodiagnostica. University of Genoa- Scuola Page 22 of 23 di

23 References Pietro Valerio Foti, Giancarlo Attinà, Saveria Spadola et al. "MR imaging of ovarian masses: classification and differential diagnosis" 2016 Springer. Izumi Imaoka, Akihiko Wada, Yasushi Kaji, et al. "Developing an MR Imaging Strategy for Diagnosis of Ovarian Masses" 2006 RadioGraphics. Iyer VR, Lee SI et al. " MRI,CT and PET\CT for ovarian cancer detection and adnexal lesion characterization" 2010 AJR Am J Roentgeno. World Health Organization Classification of Tumours 2003 Pathology and genetics of tumours of the breast and female genital organs. IARC. A. L. Valentini, B. Gui, M. Miccò, et al."benign and Suspicious Ovarian Masses-MR Imaging Criteria for Characterization: Pictorial Review" 2012, Journal of Oncology. Occhipinti Ka. "Computed tomography and magnetic resonance imaging oh the ovary" 1999 Anderson JC, ed. Gynecologic imaging. London, England. Hrick H, Chen M et al. "Complex adnexal masses: detection and characterizaition with MR imaging- multivariate analysis" Radiology. Yong-Yeon Jeong, MD Eric K. Outwater, MD Heoun Keun Kang, MD. "Imaging Evaluation of Ovarian Masses" 2000 RadioGraphics. Spencer JA1, Forstner R, Cunha TM. "ESUR guidelines for MR imaging of the sonographically indeterminate adnexal mass: an algorithmic approach" 2011 Eur Radiol. Page 23 of 23