- •Contents
- •Contributors
- •1 Introduction
- •2.1 Posterior Compartment
- •2.2 Anterior Compartment
- •2.3 Middle Compartment
- •2.4 Perineal Body
- •3 Compartments
- •3.1 Posterior Compartment
- •3.1.1 Connective Tissue Structures
- •3.1.2 Muscles
- •3.1.3 Reinterpreted Anatomy and Clinical Relevance
- •3.2 Anterior Compartment
- •3.2.1 Connective Tissue Structures
- •3.2.2 Muscles
- •3.2.3 Reinterpreted Anatomy and Clinical Relevance
- •3.2.4 Important Vessels, Nerves, and Lymphatics of the Anterior Compartment
- •3.3 Middle Compartment
- •3.3.1 Connective Tissue Structures
- •3.3.2 Muscles
- •3.3.3 Reinterpreted Anatomy and Clinical Relevance
- •3.3.4 Important Vessels, Nerves, and Lymphatics of the Middle Compartment
- •4 Perineal Body
- •References
- •MR and CT Techniques
- •1 Introduction
- •2.1 Introduction
- •2.2.1 Spasmolytic Medication
- •2.3.2 Diffusion-Weighted Imaging
- •2.3.3 Dynamic Contrast Enhancement
- •3 CT Technique
- •3.1 Introduction
- •3.2 Technical Disadvantages
- •3.4 Oral and Rectal Contrast
- •References
- •Uterus: Normal Findings
- •1 Introduction
- •References
- •1 Clinical Background
- •1.1 Epidemiology
- •1.2 Clinical Presentation
- •1.3 Embryology
- •1.4 Pathology
- •2 Imaging
- •2.1 Technique
- •2.2.1 Class I Anomalies: Dysgenesis
- •2.2.2 Class II Anomalies: Unicornuate Uterus
- •2.2.3 Class III Anomalies: Uterus Didelphys
- •2.2.4 Class IV Anomalies: Bicornuate Uterus
- •2.2.5 Class V Anomalies: Septate Uterus
- •2.2.6 Class VI Anomalies: Arcuate Uterus
- •2.2.7 Class VII Anomalies
- •References
- •Benign Uterine Lesions
- •1 Background
- •1.1 Uterine Leiomyomas
- •1.1.1 Epidemiology
- •1.1.2 Pathogenesis
- •1.1.3 Histopathology
- •1.1.4 Clinical Presentation
- •1.1.5 Therapy
- •1.1.5.1 Indications
- •1.1.5.2 Medical Therapy and Ablation
- •1.1.5.3 Surgical Therapy
- •1.1.5.4 Uterine Artery Embolization (UAE)
- •1.1.5.5 Magnetic Resonance-Guided Focused Ultrasound
- •2 Adenomyosis of the Uterus
- •2.1 Epidemiology
- •2.2 Pathogenesis
- •2.3 Histopathology
- •2.4 Clinical Presentation
- •2.5 Therapy
- •3 Imaging
- •3.2 Magnetic Resonance Imaging
- •3.2.1 Magnetic Resonance Imaging: Technique
- •3.2.2 MR Appearance of Uterine Leiomyomas
- •3.2.3 Locations, Growth Patterns, and Imaging Characteristics
- •3.2.4 Histologic Subtypes and Forms of Degeneration
- •3.2.5 Differential Diagnosis
- •3.2.6 MR Appearance of Uterine Adenomyosis
- •3.2.7 Locations, Growth Patterns, and Imaging Characteristics
- •3.2.8 Differential Diagnosis
- •3.3 Computed Tomography
- •3.3.1 CT Technique
- •3.3.2 CT Appearance of Uterine Leiomyoma and Adenomyosis
- •3.3.3 Atypical Appearances on CT and Differential Diagnosis
- •4.1 Indications
- •4.2 Technique
- •Bibliography
- •Cervical Cancer
- •1 Background
- •1.1 Epidemiology
- •1.2 Pathogenesis
- •1.3 Screening
- •1.4 HPV Vaccination
- •1.5 Clinical Presentation
- •1.6 Histopathology
- •1.7 Staging
- •1.8 Growth Patterns
- •1.9 Treatment
- •1.9.1 Treatment of Microinvasive Cervical Cancer
- •1.9.2 Treatment of Grossly Invasive Cervical Carcinoma (FIGO IB-IVA)
- •1.9.3 Treatment of Recurrent Disease
- •1.9.4 Treatment of Cervical Cancer During Pregnancy
- •1.10 Prognosis
- •2 Imaging
- •2.1 Indications
- •2.1.1 Role of CT and MRI
- •2.2 Imaging Technique
- •2.2.2 Dynamic MRI
- •2.2.3 Coil Technique
- •2.2.4 Vaginal Opacification
- •2.3 Staging
- •2.3.1 General MR Appearance
- •2.3.2 Rare Histologic Types
- •2.3.3 Tumor Size
- •2.3.4 Local Staging
- •2.3.4.1 Stage IA
- •2.3.4.2 Stage IB
- •2.3.4.3 Stage IIA
- •2.3.4.4 Stage IIB
- •2.3.4.5 Stage IIIA
- •2.3.4.6 Stage IIIB
- •2.3.4.7 Stage IVA
- •2.3.4.8 Stage IVB
- •2.3.5 Lymph Node Staging
- •2.3.6 Distant Metastases
- •2.4 Specific Diagnostic Queries
- •2.4.1 Preoperative Imaging
- •2.4.2 Imaging Before Radiotherapy
- •2.5 Follow-Up
- •2.5.1 Findings After Surgery
- •2.5.2 Findings After Chemotherapy
- •2.5.3 Findings After Radiotherapy
- •2.5.4 Recurrent Cervical Cancer
- •2.6.1 Ultrasound
- •2.7.1 Metastasis
- •2.7.2 Malignant Melanoma
- •2.7.3 Lymphoma
- •2.8 Benign Lesions of the Cervix
- •2.8.1 Nabothian Cyst
- •2.8.2 Leiomyoma
- •2.8.3 Polyps
- •2.8.4 Rare Benign Tumors
- •2.8.5 Cervicitis
- •2.8.6 Endometriosis
- •2.8.7 Ectopic Cervical Pregnancy
- •References
- •Endometrial Cancer
- •1.1 Epidemiology
- •1.2 Pathology and Risk Factors
- •1.3 Symptoms and Diagnosis
- •2 Endometrial Cancer Staging
- •2.1 MR Protocol for Staging Endometrial Carcinoma
- •2.2.1 Stage I Disease
- •2.2.2 Stage II Disease
- •2.2.3 Stage III Disease
- •2.2.4 Stage IV Disease
- •4 Therapeutic Approaches
- •4.1 Surgery
- •4.2 Adjuvant Treatment
- •4.3 Fertility-Sparing Treatment
- •5.1 Treatment of Recurrence
- •6 Prognosis
- •References
- •Uterine Sarcomas
- •1 Epidemiology
- •2 Pathology
- •2.1 Smooth Muscle Tumours
- •2.2 Endometrial Stromal Tumours
- •3 Clinical Background
- •4 Staging
- •5 Imaging
- •5.1 Leiomyosarcoma
- •5.2.3 Undifferentiated Uterine Sarcoma
- •5.3 Adenosarcoma
- •6 Prognosis and Treatment
- •References
- •1.1 Anatomical Relationships
- •1.4 Pelvic Fluid
- •2 Developmental Anomalies
- •2.1 Congenital Abnormalities
- •2.2 Ovarian Maldescent
- •3 Ovarian Transposition
- •References
- •1 Introduction
- •4 Benign Adnexal Lesions
- •4.1.1 Physiological Ovarian Cysts: Follicular and Corpus Luteum Cysts
- •4.1.1.1 Imaging Findings in Physiological Ovarian Cysts
- •4.1.1.2 Differential Diagnosis
- •4.1.2 Paraovarian Cysts
- •4.1.2.1 Imaging Findings
- •4.1.2.2 Differential Diagnosis
- •4.1.3 Peritoneal Inclusion Cysts
- •4.1.3.1 Imaging Findings
- •4.1.3.2 Differential Diagnosis
- •4.1.4 Theca Lutein Cysts
- •4.1.4.1 Imaging Findings
- •4.1.4.2 Differential Diagnosis
- •4.1.5 Polycystic Ovary Syndrome
- •4.1.5.1 Imaging Findings
- •4.1.5.2 Differential Diagnosis
- •4.2.1 Cystadenoma
- •4.2.1.1 Imaging Findings
- •4.2.1.2 Differential Diagnosis
- •4.2.2 Cystadenofibroma
- •4.2.2.1 Imaging Features
- •4.2.3 Mature Teratoma
- •4.2.3.1 Mature Cystic Teratoma
- •Imaging Findings
- •Differential Diagnosis
- •4.2.3.2 Monodermal Teratoma
- •Imaging Findings
- •4.2.4 Benign Sex Cord-Stromal Tumors
- •4.2.4.1 Fibroma and Thecoma
- •Imaging Findings
- •4.2.4.2 Sclerosing Stromal Tumor
- •Imaging Findings
- •4.2.5 Brenner Tumors
- •4.2.5.1 Imaging Findings
- •4.2.5.2 Differential Diagnosis
- •5 Functioning Ovarian Tumors
- •References
- •1 Introduction
- •2.1 Context
- •2.2.2 Indications According to Simple Rules
- •References
- •CT and MRI in Ovarian Carcinoma
- •1 Introduction
- •2.1 Familial or Hereditary Ovarian Cancers
- •3 Screening for Ovarian Cancer
- •5 Tumor Markers
- •6 Clinical Presentation
- •7 Imaging of Ovarian Cancer
- •7.1.2 Peritoneal Carcinomatosis
- •7.1.3 Ascites
- •7.3 Staging of Ovarian Cancer
- •7.3.1 Staging by CT and MRI
- •Imaging Findings According to Tumor Stages
- •Value of Imaging
- •7.3.2 Prediction of Resectability
- •7.4 Tumor Types
- •7.4.1 Epithelial Ovarian Cancer
- •High-Grade Serous Ovarian Cancer
- •Low-Grade Serous Ovarian Cancer
- •Mucinous Epithelial Ovarian Cancer
- •Endometrioid Ovarian Carcinomas
- •Clear Cell Carcinomas
- •Imaging Findings of Epithelial Ovarian Cancers
- •Differential Diagnosis
- •Borderline Tumors
- •Imaging Findings
- •Differential Diagnosis
- •Recurrent Ovarian Cancer
- •Imaging Findings
- •Differential Diagnosis
- •Value of Imaging
- •Malignant Germ Cell Tumors
- •Dysgerminomas
- •Imaging Findings
- •Differential Diagnosis
- •Immature Teratomas
- •Imaging Findings
- •Malignant Transformation in Benign Teratoma
- •Imaging Findings
- •Differential Diagnosis
- •Sex-Cord Stromal Tumors
- •Granulosa Cell Tumors
- •Imaging Findings
- •Sertoli-Leydig Cell Tumor
- •Imaging Findings
- •Ovarian Lymphoma
- •Imaging Findings
- •Differential Diagnosis
- •7.4.3 Ovarian Metastases
- •Imaging Findings
- •Differential Diagnosis
- •7.5 Fallopian Tube Cancer
- •7.5.1 Imaging Findings
- •Differential Diagnosis
- •References
- •Endometriosis
- •1 Introduction
- •2.1 Sonography
- •3 MR Imaging Findings
- •References
- •Vagina and Vulva
- •1 Introduction
- •3.1 CT Appearance
- •3.2 MRI Protocol
- •3.3 MRI Appearance
- •4.1 Imperforate Hymen
- •4.2 Congenital Vaginal Septa
- •4.3 Vaginal Agenesis
- •5.1 Vaginal Cysts
- •5.1.1 Gardner Duct Cyst (Mesonephric Cyst)
- •5.1.2 Bartholin Gland Cyst
- •5.2.1 Vaginal Infections
- •5.2.1.1 Vulvar Infections
- •5.2.1.2 Vulvar Thrombophlebitis
- •5.3 Vulvar Trauma
- •5.4 Vaginal Fistula
- •5.5 Post-Radiation Changes
- •5.6 Benign Tumors
- •6.1 Vaginal Malignancies
- •6.1.1 Primary Vaginal Carcinoma
- •6.1.1.1 MRI Findings
- •6.1.1.2 Lymph Node Drainage
- •6.1.1.3 Recurrence and Complications
- •6.1.2 Non-squamous Cell Carcinomas of the Vagina
- •6.1.2.1 Adenocarcinoma
- •6.1.2.2 Melanoma
- •6.1.2.3 Sarcomas
- •6.1.2.4 Lymphoma
- •6.2 Vulvar Malignancies
- •6.2.1 Vulvar Carcinoma
- •6.2.2 Melanoma
- •6.2.3 Lymphoma
- •6.2.4 Aggressive Angiomyxoma of the Vulva
- •7 Vaginal Cuff Disease
- •7.1 MRI Findings
- •8 Foreign Bodies
- •References
- •Imaging of Lymph Nodes
- •1 Background
- •3 Technique
- •3.1.1 Intravenous Unspecific Contrast Agents
- •3.1.2 Intravenous Tissue-Specific Contrast Agents
- •References
- •1 Introduction
- •2.1.1 Imaging Findings
- •2.1.2 Differential Diagnosis
- •2.1.3 Value of Imaging
- •2.2 Pelvic Inflammatory
- •2.2.1 Imaging Findings
- •2.3 Hydropyosalpinx
- •2.3.1 Imaging Findings
- •2.3.2 Differential Diagnosis
- •2.4 Tubo-ovarian Abscess
- •2.4.1 Imaging Findings
- •2.4.2 Differential Diagnosis
- •2.4.3 Value of Imaging
- •2.5 Ovarian Torsion
- •2.5.1 Imaging Findings
- •2.5.2 Differential Diagnosis
- •2.5.3 Diagnostic Value
- •2.6 Ectopic Pregnancy
- •2.6.1 Imaging Findings
- •2.6.2 Differential Diagnosis
- •2.6.3 Value of Imaging
- •3.1 Pelvic Congestion Syndrome
- •3.1.1 Imaging Findings
- •3.1.2 Differential Diagnosis
- •3.1.3 Value of Imaging
- •3.2 Ovarian Vein Thrombosis
- •3.2.1 Imaging Findings
- •3.2.2 Differential Diagnosis
- •3.2.3 Value of Imaging
- •3.3 Appendicitis
- •3.3.1 Imaging Findings
- •3.3.2 Value of Imaging
- •3.4 Diverticulitis
- •3.4.1 Imaging Findings
- •3.4.2 Differential Diagnosis
- •3.4.3 Value of Imaging
- •3.5 Epiploic Appendagitis
- •3.5.1 Imaging Findings
- •3.5.2 Differential Diagnosis
- •3.5.3 Value of Imaging
- •3.6 Crohn’s Disease
- •3.6.1 Imaging Findings
- •3.6.2 Differential Diagnosis
- •3.6.3 Value of Imaging
- •3.7 Rectus Sheath Hematoma
- •3.7.1 Imaging Findings
- •3.7.2 Differential Diagnosis
- •3.7.3 Value of Imaging
- •References
- •MRI of the Pelvic Floor
- •1 Introduction
- •2 Imaging Techniques
- •3.1 Indications
- •3.2 Patient Preparation
- •3.3 Patient Instruction
- •3.4 Patient Positioning
- •3.5 Organ Opacification
- •3.6 Sequence Protocols
- •4 MR Image Analysis
- •4.1 Bony Pelvis
- •5 Typical Findings
- •5.1 Anterior Compartment
- •5.2 Middle Compartment
- •5.3 Posterior Compartment
- •5.4 Levator Ani Muscle
- •References
- •Evaluation of Infertility
- •1 Introduction
- •2 Imaging Techniques
- •2.1 Hysterosalpingography
- •2.1.1 Cycle Considerations
- •2.1.2 Technical Considerations
- •2.1.3 Side Effects and Complications
- •2.1.5 Pathological Findings
- •2.1.6 Limitations of HSG
- •2.2.1 Cycle Considerations
- •2.2.2 Technical Considerations
- •2.2.2.1 Normal and Abnormal Anatomy
- •2.2.3 Accuracy
- •2.2.4 Side Effects and Complications
- •2.2.5 Limitations of Sono-HSG
- •2.3 Magnetic Resonance Imaging
- •2.3.1 Indications
- •2.3.2 Technical Considerations
- •2.3.3 Limitations
- •3 Ovulatory Dysfunction
- •4 Pituitary Adenoma
- •5 Polycystic Ovarian Syndrome
- •7 Uterine Disorders
- •7.1 Müllerian Duct Anomalies
- •7.1.1 Class I: Hypoplasia or Agenesis
- •7.1.2 Class II: Unicornuate
- •7.1.3 Class III: Didelphys
- •7.1.4 Class IV: Bicornuate
- •7.1.5 Class V: Septate
- •7.1.6 Class VI: Arcuate
- •7.1.7 Class VII: Diethylstilbestrol Related
- •7.2 Adenomyosis
- •7.3 Leiomyoma
- •7.4 Endometriosis
- •References
- •MR Pelvimetry
- •1 Clinical Background
- •1.3.1 Diagnosis
- •1.3.2.1 Cephalopelvic Disproportion
- •1.3.4 Inadequate Progression of Labor due to Inefficient Contraction (“the Powers”)
- •2.2 Palpation of the Pelvis
- •3 MR Pelvimetry
- •3.2 MR Imaging Protocol
- •3.3 Image Analysis
- •3.4 Reference Values for MR Pelvimetry
- •5 Indications for Pelvimetry
- •References
- •MR Imaging of the Placenta
- •2 Imaging of the Placenta
- •3 MRI Protocol
- •4 Normal Appearance
- •4.1 Placenta Variants
- •5 Placenta Adhesive Disorders
- •6 Placenta Abruption
- •7 Solid Placental Masses
- •9 Future Directions
- •References
- •Erratum to: Endometrial Cancer
Adnexal Masses: Characterization
of Benign Adnexal Masses
I. Thomassin-Naggara, B. Fedida, and E. Kermarrec
Contents
1 |
Introduction\ |
|
273 |
2 Part 1: MR Imaging in Diagnostic |
|
|
|
|
Pathway\ |
|
274 |
2.1 |
Context\ |
|
274 |
2.2 Which Lesions Should Be Assessed |
|
|
|
|
with MR Imaging?\ |
|
274 |
2.3 Why MR Imaging Is Useful |
|
|
|
|
to Characterize Adnexal Masses?\ |
|
275 |
3 |
Part 2: MR Protocol and Keys for Analysis\ |
|
276 |
3.1 Step 1: Prediction of the Risk of Malignancy\ |
|
276 |
|
3.2 Step 2: Prediction of the Histopathological |
|
|
|
|
Diagnosis\ |
|
276 |
Conclusion\ |
|
285 |
|
References\ |
|
285 |
I. Thomassin-Naggara (*)
Sorbonne Universités, UPMC Univ Paris 06, IUC, 75005 Paris, France
INSERM, UMR970, Equipe 2, Imagerie de l’angiogenèse, 75005 Paris, France
Department of Radiology, AP-HP, Hôpital Tenon, 4 rue de la Chine, 75020 Paris, France
Service de Radiologie, Hôpital Tenon, 4 rue de la Chine, 75020 Paris, France e-mail: isabelle.thomassin@aphp.fr
B. Fedida
Sorbonne Universités, UPMC Univ Paris 06, IUC, 75005 Paris, France
Department of Radiology, AP-HP, Hôpital Tenon, 4 rue de la Chine, 75020 Paris, France
E. Kermarrec
Department of Radiology, AP-HP, Hôpital Tenon, 4 rue de la Chine, 75020 Paris, France
Abstract
Pelvic MR imaging is the best second-line technique to characterize indeterminate or complex adnexal masses detected at transvaginal ultrasonography. The aim of this text is to explain the added value of MR and CT in the diagnostic management of a slightly symptomatic indeterminate or complex adnexal mass. The objectives of this chapter are to describe the place of MR imaging and CT imaging and to learn how to combine features from morphologic and functional sequences to accurately diagnose an adnexal mass.
The analysis is divided into two steps: The first step is to estimate the risk of malignancy based on the ADNEX MR Scoring system or EURAD score and the second step is to suggest an histopathological hypothesis combining EURAD score with the age of the patient and the morphology of the tumor.
1\ Introduction
Pelvic MR imaging is the best second-line technique to characterize indeterminate or complex adnexal masses detected at transvaginal ultrasonography.
In clinical routine, there are two very different circumstances for detecting these masses at ultrasonography. The first situation is the context of acute or subacute pelvic pain and the second one is incidental finding of an adnexal mass during
Med Radiol Diagn Imaging (2017) |
273 |
DOI 10.1007/174_2017_66, © Springer International Publishing AG
Published Online: 26 April 2017
274 |
I. Thomassin-Naggara et al. |
|
|
the assessment of a nonspecific symptom such as bleeding, chronic pelvic pain, or infertility.
In this chapter, we are not going to develop the first clinical situation which will be covered in the “Acute and chronic pelvic pain disorders” chapter about pelvic inflammatory disease and adnexal torsion. The aim of this text is to explain the added value of MR and CT in the diagnostic management of a slightly symptomatic indeterminate or complex adnexal mass.
The objectives of this chapter are to describe the place of MR imaging and CT imaging and to learn how to combine features from morphologic and functional sequences to accurately diagnose an adnexal mass.
2\ Part 1: MR Imaging
in Diagnostic Pathway
2.1\ Context
Most of the medical imaging publications recommend MR imaging to characterize complex adnexal masses without any consensus on the definition of the word “complex”. Despite a high level of evidence on the performance of MR imaging in this issue, many clinicians perform laparoscopy just based on ultrasonographic features. However, recent data on the impact of ovarian surgery on fertility are modifying the practices and render MR imaging useful especially to obtain criteria to avoid unnecessary surgery in patients with benign lesions (Buys et al. 2005). Another significant impact of MRI is the possibility to plan the surgical procedure time and then to improve the organization of our overloaded theater schedule. The surgeon needs to correctly plan the surgery and also to inform the patient of the possibility and the risks to discover unexpected lesions during the surgery. That’s why we perform more and more MR imaging in this indication.
2.2\ Which Lesions Should
Be Assessed with MR
Imaging?
MR imaging is a second-line technique after ultrasonography which is the first imaging technique to
assess pelvis abnormalities. More than 70% of adnexal masses are accurately identified using transvaginal ultrasonography with color Doppler. According to the literature, even using accurate ultrasonographic models, 20–25% of adnexal masses remain indeterminate after ultrasonography and need further examination (Kinkel et al. 2005).
To approach the definition of a complex adnexal mass, pattern recognition analysis or simple rules, which are currently the most reliable model published until now, can be used (Brun et al. 2014).
2.2.1\ Indications According
to Ultrasonographic Patterns
The main ultrasonographic patterns are divided into the following six categories:
US pattern 1: Simple cyst (i.e., unilocular anechoic cyst without solid component)
US pattern 2: Nonsimple cyst (i.e., unilocular echoic cyst without solid component)
These two first US patterns are included in the first categories of International Ovarian Tumor Analysis group classification named “Unilocular cyst” (Buys et al. 2005). This group includes the tubal benign abnormalities like hydrosalpinx, hematosalpinx, and the different echoic signal like “ground glass,” “hemorrhagic content,” and “mixed content.”
US pattern 3: Bior multilocular cyst (i.e., bior multilocular cyst without solid component)
US pattern 4: Cyst with papillary projections US pattern 5: Mixed heterogeneous mass IOTA classification groups these two last pat-
terns in the groups “unilocular solid” or “multilocular solid”. In these two categories, there is a cystic and a solid component in the described lesion.
US pattern 6: Enlarged ovaries (including purely solid mass than means more than 80% of solid component in the lesion)
These last three patterns require an ultrasonographic characterization of their solid component looking for acoustic shadowing, irregularity of the margins, and feature of the Doppler flow. These elements are usually inadequate to accurately predict the risk of malignancy.
Therefore, MR imaging can be performed in the cases with US pattern 4, 5, or 6 to suggest a histopathological diagnosis. In pattern 3, MR
Adnexal Masses: Characterization of Benign Adnexal Masses |
275 |
|
|
imaging allows to exclude a solid component and to characterize the different cystic components and it also helps to approach a histological diagnosis.
On the contrary, in categories 1 and 2, MR imaging has a very low added value except if the lesion is very large. Indeed, if an echoic cyst is larger than 7 cm or an anechoic cyst is larger than 10 cm, MRI is better to exclude a small solid component distant from the endovaginal probe that could be missed. MRI is also efficient to evaluate any associated findings such as deep pelvic endometriosis associated with endometrioma.
2.2.2\ Indications According to Simple Rules
The simple rules described by IOTA group consist in dividing ten sonographic features in two groups: benign features (B features) and malignant features (M features) (Table 1).
When at least one B feature is found and no M feature, the lesion is considered as benign whereas when at least one M feature is found and no B feature, the lesion is considered as malignant. When both B and M features are found, the lesion is considered as indeterminate as well as
Table 1 Simples rules (Timmerman et al. 2010)
Benign features |
Malignant features |
||
B1 |
Unilocular cyst |
M1 |
Irregular solid tumor |
B2 |
Solid components |
M2 |
Ascites |
present but <7 mm |
|
|
|
B3 |
Acoustic shadows |
M3 |
At least four papillary |
|
|
structures |
|
B4 |
Smooth |
M4 |
Irregular multilocular |
multilocular tumor |
solid tumor with largest |
||
with largest diameter |
diameter > or equal to 100 mm |
||
<100 mm |
|
|
|
|
|
|
|
B5 |
No blood flow |
M5 |
Very strong color Doppler |
when none B or M features is found. Applying these rules, in the group of indeterminate lesion, the risk of malignancy is 40% and MR imaging is warranted (Timmerman et al. 2010).
Recently, Timmerman et al. reviewed the level of risk according to the simple rules’ categories publishing a model of prediction of malignancy on a population of 4848 patients with a prevalence of malignancy of 34.3% (1665/4848) (Timmerman et al. 2010). This new publication suggests that the lesions categorized with an “intermediate risk” (i.e., risk of 8.3%) may also be referred for MR imaging to obtain additional findings to predict benignity (Table 2).
2.3\ Why MR Imaging Is Useful
to Characterize Adnexal
Masses?
Adnexal masses usually have multiple cystic and solid components. If the cyst is anechoic, ultrasonography is accurate to diagnose simple fluid (water-like appearance). If the mass is echoic, the presence of positive Doppler Flow allows identifying solid components. But the presence of solid component does not correspond to malignancy whereas the absence of positive Doppler Flow does not help to distinguish hypovascular solid components from nonsimple fluid lesions. The motion of the echos and the presence of a fluid level are in keeping with a nonsimple cyst. However in this type of mass, a solid tissue can be difficult to exclude.
Using pelvic MR imaging, the absence of contrast enhancement in an adnexal mass allows to exclude the presence of solid tissue if the spatial resolution is thin enough (< or =3 mm). Moreover,
Table 2 Risk of malignancy of US lesions according the simples rules (Timmerman et al. 2010)
|
Simple rules descriptors |
PPV of malignancy |
|
Very low risk |
No M feature + >2B features |
0.6% |
(1/175) |
Low risk |
No M feature + 2B features |
1.3% |
(20/1560) |
|
No M feature + B1 feature |
|
|
Intermediate risk |
No M feature + 1B feature |
8.3% |
(60/722) |
|
(except B1) |
|
|
Elevated risk |
No features |
41.1% (451/1096) |
|
|
Equal number of M and B features |
|
|
|
More B than M features present |
|
|
Very high risk |
More M than B features present |
87.5% (1133/1295) |
p<0.05
276 |
I. Thomassin-Naggara et al. |
|
|
the combination of T2W, T1W, DW, and T1W after intravenous injection of chelates of gadolinium allows recognizing most cystic components seen in adnexal masses. The addition of DW and DCE MR imaging is reliable to characterize solid components distinguishing between benign, borderline, and invasive malignant tissue. By definition, a solid tissue enhances after gadolinium injection. However, any internal enhancement does not correspond to solid tissue. A solid tissue includes solid papillary projection, irregular septa, mural nodule, and purely solid mass (Thomassin-Naggara et al. 2013). Smooth septa whatever the thickness is considered as solid component but not solid tissue.
Thus, MR imaging analysis is performed in two steps: the first step evaluates the risk of malignancy and the second step addresses the histopathological type of ovarian or tubal tumors.
3\ Part 2: MR Protocol and Keys
for Analysis
3.1\ Step 1: Prediction of the Risk
of Malignancy
When a pelvis mass is discovered, the first step is to determine its origin. Thus, normal ipsilateral ovarian parenchyma needs to be identified either as a crescent at the periphery of the mass or in a different site distant from the pelvic mass (suggestive of an extra-ovarian origin). If no ovarian parenchyma is visible, we should look for the ovarian pedicles to find the location of ovarian fossae and verify if the ovarian pedicle is adjacent to the mass. That’s why the MR protocol should include an anatomical lombo-pelvic sequence with slices from the mid-kidneys to the pubal symphysis which is best performed with a T2W sequence. Moreover, a sagittal T2W sequence is recommended to evaluate the mass and its relationship with the uterus. At the end, when a tubal origin is suspected, coronal views in T2WI are useful to confirm this hypothesis.
The absence of solid tissue is a main feature to suggest a low risk of malignancy (<5%) (Thomassin-Naggara et al. 2013). By definition,
a solid tissue enhances after gadolinium injection but any internal enhancement does not always correspond to solid tissue. Indeed, smooth septa are not considered as solid tissue. This feature is included in the expression “solid component” but not considered as solid tissue. Thus, a solid component groups unenhanced elements, such as clots and debris, and enhanced tissue including smooth septa and solid tissue. Solid tissue corresponds to irregular septa, solid papillary projection (>3 mm), mural nodule, and purely solid mass.
In our experience, unilocular cyst with solid tissue with a simple fluid content, or endometriotic contents or fatty contents have a very low risk of malignancy (<2%). A unilocular cyst with another type of fluid content has also a low risk of malignancy (<5%).
A bior a multilocular cyst without solid tissue again has a low risk of malignancy (<5%).
When a solid tissue is detected, the analysis of T2W signal, DW signal, and DCE MR signal within the solid tissue is useful. A solid tissue in low T2W signal and low DW signal has a very low risk of malignancy (<2%) (Thomassin-Naggara et al. 2013). If a solid tissue displays either an intermediate T2W signal or a high signal on DW sequence, time intensity curves comparing solid tissue to adjacent external myometrium are useful (Thomassin-Naggara et al. 2013). If the solid tissue enhances according to a type 1 time intensity curve, the PPV of malignancy is <5%. If the solid tissue enhances according to a type 3 time intensity curve, the PPV of malignancy is higher than 95%. If the solid tissue enhances according to a type 2 time intensity (ThomassinNaggara et al. 2013). In our experience, less than 15% of the lesions remain indeterminate. Thus, an MR classification has been developed named ADNEX MR Score which is under European validation (EURAD study) (Table 3).
3.2\ Step 2: Prediction
of the Histopathological
Diagnosis
If the first step is feasible by any junior radiologist or a general radiologist, this second step
Adnexal Masses: Characterization of Benign Adnexal Masses |
277 |
|
|
Table 3 ADNEX MR score or EURAD score (Thomassin-Naggara et al. 2013)
|
|
PPV of |
|
|
malignancy |
Score 1 |
No adnexal mass |
0% |
Score 2 |
Unilocular simple cyst or tube |
<2% |
|
Endometriotic lesion, no |
|
|
internal Gd+ |
|
|
Fatty lesion, no solid tissue |
|
|
No wall enhancement |
|
|
Solid tissue in low T2W and |
|
|
low DW signal |
|
Score 3 |
Unilocular nonsimple cyst |
<5% |
|
(excl. fatty and endometriotic) |
|
|
Multilocular cyst, no solid |
|
|
tissue |
|
|
Solid tissue with TIC type 1 |
|
|
|
|
Score 4 |
Solid tissue with TIC type 2 |
5–95% |
Score 5 |
Solid tissue with TIC type 3 |
>95% |
|
Peritoneal implants |
|
|
|
|
A lesion with a solid tissue corresponds to MR categories 4, 5, and 6
a
c
requires deeper knowledge of functional and organic ovarian lesions. The analysis is based on the clinical history and the different MR parameters useful to analyze cystic and solid components characteristics, the shape, the wall, and the size of the lesion. Sometimes, the differentiation between functional and organic cysts is difficult and ultrasonographic follow-up helps to the make the differential diagnosis.
As for ultrasonography, we differentiate the following six categories of MR features:
MR pattern 1: Simple cyst
Simple cyst corresponds to a unilocular cyst lesion without internal enhancement with a fluid content that presents a low T1W signal, a high T2W signal, a low DW signal and a high ADC (Fig. 1). Nonspecific cyst, serous cystadenoma, follicular cyst, pseudo peritoneal cyst, and hydrosalpinx are usually classified in this pattern (Table 4).
b
Fig. 1 MR pattern 1: Serous benign cystadenoma (a: Axial T2W sequence, b: Axial T1W sequence, c: Axial T1W sequence after gadolinium injection). Step 1: Unilocular cyst without internal enhancement with a fluid
content in high T2W and low T1W signal corresponding to EURAD score 2. Step 2: There is no specific feature that helps to distinguish a functional cyst from an organic cyst
Table 4 Adnexal masses without solid tissue
Diagnostic hypothesis |
Clinical history |
Fluid |
Shape |
Wall |
Specific sign |
|
|
|
|
|
|
Pattern 1 = simple cyst |
|
|
|
|
|
|
|
|
|
|
|
Follicular cyst |
Premenopausal woman |
High T2 |
Oval |
Fine Gd+ |
Spontaneous disappearance |
|
|
|
|
|
|
Unspecified cyst |
Menopausal |
High T2 |
Oval |
Gd− |
– |
Serous cystadenoma |
40–50 year old |
High T2 |
Oval |
Gd+ |
Calcospherites |
|
|
|
|
|
|
Hydrosalpinx |
Any age |
High T2 |
Tubular (CoroT2W) |
Gd+ |
Partial septa |
|
|
|
|
|
|
Pseudoperitoneal cyst |
After surgery or pelvic |
High T2 |
Pelvic shape |
Gd− |
Deformable at palpation |
|
inflammatory disease |
|
|
|
|
|
|
|
|
|
|
Pattern 2 = nonsimple cyst |
|
|
|
|
|
|
|
|
|
|
|
Luteal cyst |
Premenopausal |
Variable T1W signal |
Round |
Thick Gd+/DW+ |
Spontaneous disappearance |
|
|
|
|
|
|
Endometrioma |
Premenopausal |
Low T2W signal T1W>fat |
Round |
Gd− |
Clots |
Dermoid cyst |
<45 year old |
HypoT1 FS |
Round |
|
|
|
|
|
|
|
|
Hématosalpinx |
Premenopausal |
Variable T1W signal |
Tubular |
Gd+ |
|
|
|
|
|
Franges+ |
|
|
|
|
|
|
|
Tubo ovarian abscess |
Premenopausal |
High T1W and DW signal |
Round + tubular |
Thick Gd+ |
Fatty infiltration |
|
|
with low ADC value |
|
|
|
|
|
|
|
|
|
Pattern 3 = multilocular lesion |
|
|
|
|
|
|
|
|
|
|
|
Mucinous benign |
30–50 year old |
Loculi with different |
Oval |
Gd+ |
None |
cystadenoma |
|
signal intensity |
|
|
|
|
|
|
|
|
|
Struma ovarii |
40–50 year old |
Presence of colloid |
Oval |
Gd+ |
None |
|
|
|
|
|
|
Adult granulosa |
55 year old |
Hemorrhagic loculi |
Oval |
Gd+ |
Endometrial thickening |
|
|
|
|
|
adenomyosis |
|
|
|
|
|
|
Sertoli Leydig |
20–30 year old |
Hemorrhagic loculi |
Oval |
Gd+ |
Hyperandrogenic syndrome |
|
|
|
|
|
|
Yolk sac |
20 year old αFP > 1000 |
Hemorrhagic loculi |
|
|
|
278
.al et Naggara-Thomassin .I
Adnexal Masses: Characterization of Benign Adnexal Masses |
279 |
|
|
MR pattern 2: Nonsimple cyst
Nonsimple cyst corresponds to a unilocular cyst that has no internal enhancement with a fluid content that presents an intermediate or high T1W signal, a variable T2W signal, DW signal, and ADC maps. The analysis is based on the signal of the cystic content before and after fat suppression, the presence or the absence of wall enhancement, and the signal on the DW sequence (Table 4).
MR pattern 3: Multilocular cyst
In a multilocular cyst, there are smooth septa that enhance after gadolinium injection. Smooth septa are not considered as solid tissue. On T2W sequence, a luteal cyst with fibrinous component may look like a multilocular cyst. The difference between septa and fibrinous components is the presence of septal enhancement.
Septal enhancement is a key feature that helps to distinguish septa from fibrinous components that do not enhance after contrast media injection. In that case, the cyst can be considered as
unilocular indicating the luteal cyst. A lesion classified in this pattern “3” does not include any solid tissue.
MR imaging is useful in this group either in large lesion size or to characterize the cystic component owing to the combination of the different MR sequences to suggest a histopathological subtype. The different cystic fluid types found in ovarian tumors are:
––Mucin (moderate high T1W signal, intermediate T2W signal, high DW signal, high ADC value)
––Colloid (very low T2W signal, moderate high T1W signal)
––Blood (high T1W signal with and without fat suppression, intermediate T2W signal)
––Pus (moderate high T2W signal, intermediate T2W signal, high DW signal, low ADC value)
––Fat (high T1W signal that decreases after fat suppression) (Fig. 2)
MR pattern 4: Cyst with papillary projections
a |
b |
d
c
Fig. 2 MR pattern 3: Mature cystic teratoma (a: Axial T2W sequence, b: Axial T1W sequence, c: Axial T1W sequence with fat suppression, d: Axial T1W sequence with fat suppression after gadolinium injection). Step 1: Multilocular cyst without solid tissue with a fluid content
in high T2W, high T1W signal, and low T1 after fat corresponding to EURAD score 2. Step 2: The presence of fatty content and the absence of colloid suggests a teratoma. The absence of protuberance in this case strongly suggests a mature cystic teratoma
280 |
I. Thomassin-Naggara et al. |
|
|
A papillary projection corresponds to solid tissue and centrally enhances after gadolinium injection (Fig. 3). This feature is important to distinguish a solid papillary projection from a small loculus before performing any time intensity curve (cause of false positive). Moreover, in tubal distension
pseudopapillary projections with the same size, regularly located on the cystic wall, indicate the cogwell sign (Ghattamaneni et al. 2009). A tubular shape in another plan may help to diagnose hydrosalpinx. Final differential diagnosis is a clot that does not enhance after gadolinium injection.
a |
b |
d
c
e
Fig. 3 MR pattern 4: Serous benign cystadenoma (a: Axial T2W sequence, b: Axial T1W sequence, c: Axial T1W sequence with fat suppression after gadolinium injection, d: Axial DWI sequence, e: Axial DCE MR sequence). Step 1: Unilocular cyst with solid tissue that corresponds to solid papillary projection that displays a
high T2W signal, low DW signal, and enhances according a TIC type 1 corresponding to EURAD score 3 (probably benign). Step 2: Unilocular cyst with papillary projection higher than 1 mm suggests a serous cystadenoma. Benign characteristics suggest a benign serous cystadenoma
Adnexal Masses: Characterization of Benign Adnexal Masses |
281 |
|
|
The presence of solid papillary projections is pathognomonic of the presence of epithelial tumors but is not synonymous of a borderline or benign lesion. There are two main types of solid papillary projections:
––Larger than 1 mm in size found in serous cystadenomas which displays in benign lesion a
low T2W and low DW signal and a type 1 time intensity curve (TIC) and displays in borderline cystadenomas an intermediate T2W signal, a high DW signal and a type 2 TIC (Fig. 4).
––Smaller than 1 mm found in borderline mucinous cystadenomas. No papillary projection is
a |
b |
d
c
e
Fig. 4 MR pattern 4: Borderline serous cystadenoma (a: Axial T2W sequence, b: Axial T1W sequence, c: Axial T1W sequence with fat suppression after gadolinium injection, d: Axial DWI sequence, e: Axial DCE MR sequence). Step 1: Unilocular cyst with solid tissue that corresponds to grouped solid papillary projections that
display a high T2W signal, high DW signal, and enhances according a TIC type 2 corresponding to EURAD score 4 (indeterminate). Step 2: Unilocular cyst with papillary projection higher than 1 mm suggests a serous cystadenoma. Suspicious characteristics suggest a borderline serous cystadenoma
282 |
I. Thomassin-Naggara et al. |
|
|
found in benign mucinous cystadenoma that displays only smooth septa.
In this pattern, only unilocular or multilocular cyst with solid papillary projections and no other type of solid tissue is present (see below in pattern 5).
When solid papillary projections are grouped, the distinction with a mural nodule can be difficult. This is important to distinguish a borderline cystadenoma (with solid papillary projections) from invasive malignant cystadenocarcinoma (mural nodule) when this tissue displays an intermediate T2W signal, a high DW signal, and a type 2 TIC. A mural nodule (or “solid portion”) corresponds to a pathological thickening of the wall due to malignant proliferation and thus an
obtuse angle with the wall is seen. In contrast, a group of papillary projections has an acute angle with the wall.
MR Pattern 5: Mixed mass
This pattern corresponds to a large variety of tumors that includes both cystic and solid components (Fig. 5). The analysis of gadolinium enhancement helps identify tumors that truly display a solid portion (echoic cystic portion at ultrasonography may look like solid tissue). The differential diagnoses are enlisted in detail in Table 5 and this category comprises the largest number of diagnoses. MR imaging is also useful to determine the origin of the tumor and may help to recognize a non-ovarian mass.
a |
b |
d
c
Fig. 5 5 MR pattern 5: Invasive cystadenocarcinoma (a: Axial T2W sequence, b: Axial DW sequence, c: Axial T1W sequence with fat suppression after gadolinium injection, d: Axial DCE MR sequence). Step 1: Mixed mass with solid tissue that corresponds to mural nodule
that displays intermediate T2W signal, high DW signal, and enhances according a TIC type 2 corresponding to EURAD score 4. Step 2: The morphology, the age of the patient (65-year-old woman), and the suspicious findings suggest an invasive cystadenocarcinoma
Adnexal Masses: Characterization of Benign Adnexal Masses |
283 |
|
|
MR Pattern 6: Purely solid mass
The initial finding is an enlarged ovary due to an ovarian edema that induces an intermediate T2W signal, a high DW signal, and a variable enhancement. Follicles are located in the periphery of the ovary. The different causes of ovarian edema are detailed in Table 5.
Table 5 Adnexal masses with solid tissue
When there is a solid mass, the first question to answer is the origin of the lesion. The most common ovarian solid tumor is fibrothecoma, with the differential diagnosis of uterine leiomyoma which is the most frequent parauterine mass. The other diagnosis are neurogenic tumors such as schwannoma (main feature: anterior displace-
Diagnosis |
Clinical history |
Fluid |
Solid |
Specific sign |
Pattern 4 = cyst with papillary projections |
|
|
|
|
|
|
|
|
|
Benign serous |
40–50 YO |
Simple |
Low T2 and DW |
|
cystadenoma |
|
|
signal/type 1 TIC |
|
Borderline serous |
40–50 YO |
Simple |
Intermediate T2W |
|
cystadenoma |
|
|
signal/type 2 TIC |
|
|
|
|
|
|
Borderline mucinous |
30–50 YO |
Loculi of different SI |
Low T2W signal/High |
Large |
cystadenoma |
|
|
DW signal |
|
Pattern 5 = mixed mass |
|
|
|
|
Cystadenofibroma |
40–50 YO |
Loculi of different SI |
Low T2 and DW |
|
|
|
|
signal/type 1 or 2 TIC |
|
Ovarian and tubal |
Ménopausal |
Variable according |
Intermediate T2W |
Peritoneal |
cystadenocarcinoma |
CA125 +++ |
pathological subtype |
signal/type 3 TIC |
implants |
|
|
|
|
|
Mature cystic teratoma |
<45 YO |
Fat |
Variable |
None |
|
|
|
|
|
Metastasis |
Premenopausal |
Multilocular |
|
Intestinal primary |
|
|
|
|
tumor (colon) |
Tubo ovarian abscess |
Premenopausal |
High DW signal with |
Intermediate T2W |
Fatty infiltration |
|
|
low ADC values |
signal/thick wall with |
|
|
|
|
vascularization |
|
Pattern 6 = purely solid mass |
|
|
|
|
|
|
|
|
|
Fibrothecoma |
50 YO |
NA |
Low T2 and DW |
Cellular subtype |
|
|
|
signal type 1 TIC |
intermediate |
|
|
|
|
T2W signal |
|
|
|
|
|
Brenner |
40–80 YO |
NA |
Low T2 and DW |
Calcosphérites |
|
|
|
signal type 1 or 2 TIC |
|
Sclerosing stromal tumor |
30 YO |
|
Low T2 and DW |
|
|
|
|
signal type 2 TIC |
|
|
|
|
without wash out |
|
Granulosa cell tumor |
30 YO E2 et |
NA |
T2W intermediate |
Hemorrhagic |
(young) |
inhibin |
|
signal—High DW |
center |
|
|
|
signal type 2 or 3 TIC |
|
|
|
|
|
|
Sertoli-Leydig |
<30 YO |
NA |
Similar to granulosa |
Androgenic |
|
|
|
cell tumor |
|
Mature solid teratoma |
<45 YO |
NA |
Intermediate T2W |
High T1 signal |
|
|
|
signal |
fatty spots |
Dysgerminoma |
20–30 YO |
|
Intermediate T2 |
|
|
|
|
signal—high DW |
|
|
|
|
signal, type 2 TIC |
|
|
|
|
|
|
Ovarian and tubal |
>50 YO |
|
Intermediate T2 |
Peritoneal |
cystadenocarcinoma |
|
|
signal—high DW |
implants |
|
|
|
signal—type 3 TIC |
|
|
|
|
|
|
Metastasis |
Premenopausal |
NA |
Intermediate T2 |
Breast or stomach |
|
|
|
signal—high DW |
cancer |
|
|
|
signal—type 3 TIC |
|
|
|
|
|
|
284 |
I. Thomassin-Naggara et al. |
|
|
ment of posterior peritoneum), GIST tumor (main feature: intense homogeneous enhancement with cystic changes in the center part of the lesion), and pelvic lymph nodes (main feature: perivascular).
When the lesion is originating from the ovary, MR criteria are accurate to differentiate benign
from malignant tumors but less reliable for tissue characterization (Fig. 6). In this pattern, clinical history, biological markers, and CT scan are useful (Table 5). CT scan may help to detect calcifications which are suggestive of ovarian leiomyoma if they are coarse or suggestive of Brenner tumor if they are amorphous and central.
a
c
Fig. 6 MR pattern 6: Lymphoma (a: Axial T2W sequence, b: Axial DWI sequence, c: Axial DCE MR sequence). Step 1: Bilateral purely solid masses that display an intermediate T2W signal, high DW signal, and enhance according a TIC type 3 corresponding to EURAD
b
score 5 (probably malignant). Step 2: The morphology and the score suggest invasive malignancy. The bilaterality and the age of the patient (45-year-old woman) suggest either hematological disorder or ovarian metastasis