Corinne Balleyguier, Radiology

Pierre Duvillard, Pathology

Gustave Roussy, Villejuif

From Imaging to Pathology : How to assess Benignity in Rare Ovarian Tumors?

How to assess Benignity in Rare Ovarian Tumors?

�  Imaging ?? �  Nearly never… �  Excepted for some functional ovarian lesions

�  Simple functional cyst �  Haemorraghic functional cyst �  ..

�  Some common benign ovarian lesions �  Endometrioma �  Ovarian fibroma

�  Pathology?? �  Nearly ever… �  To avoid for functional lesions …

Functional Ovarian Lesions

Functional ovarian cyst: YES

�  Ultrasound may assess the content of a liquid cyst

�  Harmonic imaging may be useful to better define cystic content

Color Döppler?

�  Color Döppler is not accurate: �  In 30 % of cases, arterial

flow is found in cystic wall

�  Usually with a low resistive index

�  Be careful to misunderstanding with a malignant lesion !!!

Haemorrhagic functional cyst: YES

Internal content with thin walls

No blood flow inside thin walls

The cyst must disappeared on short time follow-up at D6

NO MRI !!

Endometrioma: YES

�  Ultrasound is usually enough

�  Typical features: � Thin echoes,

homogeneous blood cyst

Complex endometrioma: US/MRI

�  Rarely, clots may simulate papillary projections

�  Additional MRI is useful

T1

T1 + Fat Sat

T2

Endometrioma Hyperintense T1w Hyper / Hypointensity T2w Hyperintense T1+ FS

And Rare Ovarian Tumors ??

What are Rare Ovarian Tumors ?

Germ cell ovarian tumors

Immature teratoma

Monodermal teratoma (struma ovarii)

Carcinoid T Neuroectodermic T

Non teratomatous T (Dysgerminoma)

Yolk sac T Embryonnary carcinoma

Non gravidic choriocarcinoma Polyembryoma

Mixed germ cell Tumeurs

Ovarian tumor classification OMS 2003

Stromal Tumors

Fibroma Thecoma

Fibrosarcoma Stromal T with minor

sex-cord differenciation

Sclerosing stromal T

Sex cord ovarian T

Granulosa stroma cell T

Sertoli stromal cell T

Sex cord of mixed or unclassified cell

type Gynandroblastoma

Indifferenciated sex cord T

Steroïd T

Stromal Luteoma Leydig cell T Steroid cell T

Ovarian tumor classification OMS 2003

To play in defence or

what are the findings for benign?

Pure solid ovarian tumor on

ultrasound

Ovarian Fibroma �  Diagnosis of ovarian fibroma may nearly be assess on

imaging : US + MRI �  Ultrasound findings:

�  Solid ovarian mass �  Homogeneous content �  Arterial flow

�  Ultrasound may be doubtful in case of old ovarian fibroma: �  Heterogenous �  Posterior attenuation �  Low blood flow

�  èMRI

Ovarian Fibroma

Ovarian Fibroma : MRI

�  MRI is the best imaging examination to assess fibrous content �  Hypointense signal : T1w and

T2w �  Moderate to high intense uptake

�  Enhancing curves lesion / myometrium may be useful

�  Fibrothecoma : �  Hypointense signal : T2w �  Intense uptake after injection

Ovarian Fibroma

Thomassin-Naggara, I. et al. Radiology 2008;0:2481071120

Serous Borderline Cystadenoma

Bénin

Borderline

Benign

Malignant

Right Fibroma Left Fibrothecoma

Stromal Ovarian Tumors (Fibroma, Thecoma)

�  Unilateral tumors nearly always benign �  Solid content, white/yellow colour, homogenous �  Medium size : 6 cm �  Histologically, architecture is fasciculated without any

atypia or mitoses �  Good prognosis allows conservative surgery,

especially for young women

Homogenous, echoic Cyst on

Ultrasound

Mature Teratoma

Echoic, homogenous cyst

Teratoma : Germ Cell Tumour

� Ultrasound features can vary according internal content : cyst, fat, calcification.

� Ultrasound diagnosis may be difficult : � A dermoïd cyst may mimic intestinal loops

Cystic Mature Teratoma

MRI may assess fatty content � Fat signal characterization: � Hyperintense signal : T1w � Hyperintense signal : T2w � Hypointense signal: T1w with fat

suppression

T1w T2w

T1 FS

Cystic mature teratoma

Benign Teratoma : Pathology

�  Polydermal teratoma: � Solid (15-20 % of solid teratoma) � Cystic (dermoïd cyst)

�  27-44% of all ovarian tumors �  Non specific clinical symptoms �  Diameter usually < 15 cm �  Bilateral in15% of cases, sometime multiple �  External wall smooth, half-solid, half-cystic with pilo-

sebaceous tissue �  Very heterogenous on pathology including components of

the 3 primitive mature tissues.

Benign Teratoma

� Monodermal dedicated � Struma Ovarii � Ovarian carcinoïd T

�  Insulet carcinoïds � Trabecular carcinoïds � Mucinous carcinoïds (globlet cell carcinoïds)

� Strumal carcinoïds

Attacking Game or How to find Malignant Features …

Most common rare malignant Ovarian Tumors…

Immature Teratoma Granulosa cell Tumor

Immature Teratoma?

�  Immature teratoma is rare � Difficult diagnosis on imaging �  Imaging :

�  Heterogenous internal content �  Haemorrhagic content (MRI++) �  Heterogenous, intense uptake �  Large size �  Multiple irregular calcifications �  Tissue thickening within Rokitansky’s

protuberance

Immature Teratoma

Pathologist : Referee

Immature Teratoma � Clinical features :

� 3% of ovarian teratoma (nearly 20% of primary malignant germ cell tumors and 10-20% of malignant ovarian tumors occuring before 20 yo).

� Usually revealed with an abdominal mass and abdominal pain.

� Extra ovarian lesions in 33% of cases (peritoneal implants).

� Large tumors (18 cm medium size), usually unilateral with rupture or break of capsula in 50% of cases.

Immature Teratoma �  Microscopic features:

�  Polymorphous lesions including variable amount of mainly neurectodermal immature tissue.

�  Other immature content are possible : ◆  Embryologic epithelial tissue (endodermal,

ectodermal..). ◆  Immature mesenchymatous tissue (cartilage,

striated muscle…). ◆  Liver, renal, vitellin tissue...

�  Mature tissue may be associated.

Immature Teratoma

�  Treatment and prognosis: � According tumor stage and tumor grade. � Conservative surgery if possible + chemotherapy (BEP)

for tumors grade 2 and 3 and stage II and III. � Clinical complete response is obtained in nearly all

cases after CT (77% of 5 years remission). � Residual peritoneal lesions may be detected (fibrous

nodule). � Growing teratoma syndroma is exceptionnal.

Pitfall: Growing Teratoma �  Multifocal peritoneal

extension of an immature teratoma after complete response with CT : �  Benign lesion �  Surgery may be complete to

remove all peritoneal implants �  Nimkin K, Pediatr Radiol.

2004 Mar;34(3):259-62.

Granulosa Cell Tumor �  Rare ovarian T (0.6-3% of all ovarian T)

�  5% of malignant lesions �  Mesenchymatous and sex-cord like

tumors �  Two types:

�  Adult (AGT) �  Juvenile (JGT) : malignancy risk is higher

�  Medium size : 10 cm �  Hormonal clinical symptoms �  Partly cystic, haemorrhagic content

Adult Granulosa Cell T 35 yo

15 yo Juvenile Granulosa Cell T

Pathologist : Referee

Adult Granulosa Cell Tumors �  Clinical features :

� 6% of malignant ovarian tumors � Usually diagnosed after menopause � Associated to hyperestrogenic features in 75% of

cases � Diagnosed at stage 1 in 90% of cases � Unilateral in 85% of cases, variable size,

heterogenous with capsule rupture in 10 -12% of cases

Juvenile Granulosa Cell Tumors

� Clinics: � 5% of granulosa cell tumors and 97% are

diagnosed before 30 years � Hormonal features in a child � Unilateral in 98% for stage I cases � Macroscopic features are similar to those of Adult

form tumors

Granulosa Cell Tumors

� Prognostic factors : � Stage at diagnosis

� Evolution and treatment: � Malignant lesions with low progression, late

recurrence in adult (20% at 5 years) � Death rate : 12.5% � Surgical treatment :

� Conservative for juvenile form stage IA

Across the Line… Very rare Ovarian Tumors…

Does Imaging help to diagnose a rare malignant Ovarian Tumor?

�  Common features to detect : � Size > 10 cm � Haemorrhagic content : ultrasound, MRI (++) �  Irregular calcifications � Central necrosis: MRI (hyperT2, hypoT1, peripheral

heterogenous enhancement) �  Jung SE, Radiographics. 2002

�  Ascitis �  Peritoneal carcinomatosis �  Lymph node

Endodermal sinus Tumor : Yolk sac T

�  Rare malignant germ cell tumor (< 1 % malignant T) � 20-30 yo

�  Variable feature (cystic to solid) �  Imaging features:

� Haemorrhagic content � Hyperintense uptake � Heterogenous

Yolk Sac Tumor �  Clinics:

� 20% of malignant germ cell ovarian tumors (medium age 16-19 yo) (10% before10 yo)

� Fast growing tumors : abdominal mass, pelvic pain. Emergency for surgery : risk of ovarian torsion or tumor rupture.

� α-foetoprotein synthesis (high level (>1000 ng/ml).

Yolk sac Tumor � Macroscopic features:

� Large tumor (15 cm), unilateral, sometimes peritoneal carcinomatosis.

� External wall smooth, rupture in 25% of cases. � Solid and cystic, bloody content, necrosis � Other germ cell tumor may be associated (15% of

dermoïd cyst).

� Prognostic factors � Clinical stage : 5 years survival 70-90% for stage 1

�  30 à 50% for other stage. � Residual lesions after surgery � Liver lesions.

Choriocarcinoma �  < 1 % malignant T �  15 yo �  Imaging features :

� Necrosis � Hypervascularization � Peripheral calcifications

�  Biology : � βHCG serous elevation with a non gravid uterus

�  Treatment and prognosis: �  Very aggressive tumors with peritoneal extension �  Same treatment as other malignant germ cell tumors.

Conclusion �  To assess benignity in rare ovarian

tumors ……. �  With pathology: YES, usually �  With surgery…

�  Imaging : NO �  Exception :

�  Functional lesions �  Fibrous tumors �  Mature teratoma : +/-

�  Imaging as an adjunct tool : �  Necrosis, calcifications, blood