Value of magnetic resonance imaging for the diagnosis of ovarian tumors: a review. J Comput Assist Tomogr. 2008;32:712-723. [PMID: 18830100 DOI: 10.1097/rct.0b013e31815881ef]

O-RADS MRI SCORE: An Essential First-Step Tool for the Characterization of Adnexal Masses

The ovarian-adnexal reporting and data system on magnetic resonance imaging (O-RADS MRI) score is now a well-established tool to characterize pelvic gynecological masses based on their likelihood of malignancy. The main added value of O-RADS MRI over O-RADS US is to correctly reclassify lesions that were considered suspicious on US as benign on MRI. The crucial issue when characterizing an adnexal mass is to determine the presence/absence of solid tissue and thus need to perform gadolinium injection. O-RADS MR score was built on a multivariate analysis and must be applied as a step-by-step analysis: 1) Is the mass an adnexal mass? 2) Is there an associated peritoneal carcinomatosis? 3) Is there any significant amount of fatty content? 4) Is there any wall enhancement? 5) Is there any internal enhancement? 6) When an internal enhancement is detected, does the internal enhancement correspond to solid tissue or not? 7) Is the solid tissue malignant? With its high value to distinguish benign from malignant adnexal masses and its high reproducibility, the O-RADS MRI score could be a valuable tool for timely referral of a patient to an expert center for the treatment of ovarian cancers. Finally, to make a precise diagnosis allowing optimal personalized treatment, the radiologist in gynecological imaging will combine the O-RADS MRI score with many other clinical, biological, and other MR criteria to suggest a pathological hypothesis. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY STAGE: 3.

The value of the added diffusion-weighted images to multiparametric MRI in the early diagnosis of uterine cervix cancers and nodal assessment

Background

Cervical cancer still one of the most common causes of tumor-related death in developing countries presented in younger women. In this study, we aimed to evaluate the value of diffusion-weighted MRI in early diagnosis of malignant cervical lesions, to assess metastatic adenopathy, peritoneal dissemination, and possible tumor recurrence, and determine treatment response. This study included 60 patients with abnormal vaginal bleeding and suspected cervical lesion by US. A histopathological biopsy was done. Pelvic MR with DWI and dynamic contrast-enhanced MRI were done for all patients.

Results

According to the histopathological findings, we divided our studied 60 patents into two groups: group I, malignant lesions (46 lesions; 76.7%), and group II, benign lesions (14 lesions; 23.3%). Multiparametric MRI could detect all cervical lesions but with poor pathologic characterization, achieving 72.37% sensitivity, 37.50% specificity, 63.33% accuracy, 76.19% PPV, and 33.33% NPV. When compared with DWI with ADC value measurements at high b value (b = 800) to MRI exam, it showed a higher diagnostic accuracy with good lesion pathological characterization that achieved 95.65% sensitivity, 71.43% specificity, 90% accuracy, 91.67 PPV, and 83.33% NPV. The mean ADC value for malignant lesions was 0.86–1.1, mean = 0.92 ± 0.71 × 10−3 mm2/s, while the mean ADC value in the benign lesion group was 1.18 ± 0.1 × 10–3 mm2/s.

Conclusion

Comparing DWI with ADC values measurements at high b value to the multiparametric MRI examination of the female pelvis increases the sensitivity, specificity, and diagnostic accuracy of characterization and early diagnosis of cervical malignant focal lesions and reduces the need for intravenous contrast administration.

Management of Large Pediatric and Adolescent Ovarian Neoplasms with a Leak-Proof Extracorporeal Drainage Technique: Our Experience Using a Hybrid Minimally Invasive Approach

STUDY OBJECTIVE

In a pediatric setting, laparoscopic management of large cystic ovarian neoplasms with low malignancy probability is not suitable, because of the mass size; nevertheless, an effort should be made to be as minimally invasive as possible, without violating the principles of oncologic surgery. We describe our experience in managing these neoplasms with leak-proof extracorporeal drainage through mini laparotomy, followed by cyst excision or oophorectomy.

DESIGN

Case series study, describing interventions and outcomes.

SETTING

Department of pediatric surgery in a tertiary pediatric and adult university hospital.

PARTICIPANTS

Pediatric patients affected by large cystic ovarian mass.

INTERVENTIONS

Hybrid minimally invasive approach using leak-proof extracorporeal drainage.

MAIN OUTCOME MEASURES

Data on demographic characteristics, tumor marker values, and imaging findings were collected and analyzed. Outcome of surgical technique was evaluated and reported.

RESULTS

Between 2011 and 2018, 17 patients (mean age, 10.2 years; range, 2-14 years) affected by large cystic ovarian mass, were eligible for this technique. All patients had negative preoperative tumor markers. Of the seventeen subjects, 13/17 girls (76%) underwent pelvic magnetic resonance imaging. No sign of lymphadenopathy or metastasis was found. Surgery was successful in all patients, with ovarian preservation in 5/17 cases (29.4%). Mean surgical time was 98 minutes; no intra-abdominal leakage of neoplasm content or postoperative complications occurred. Mature cystic teratoma was the most frequent histopathological diagnosis (71%).

CONCLUSION

After a thorough patient selection, the management of large cystic ovarian neoplasms with leak-proof extracorporeal drainage performed through a mini laparotomy is a feasible and safe approach, with excellent cosmetic results. When achievable, ovarian-sparing surgery has to be considered.

Differentiating Between Low- and High-grade Glioma Tumors Measuring Apparent Diffusion Coefficient Values in Various Regions of the Brain

Objectives

Our study aimed to apply the apparent diffusion coefficient (ADC) values to quantify the differences between low- and high-grade glioma tumors.

Methods

We conducted a multicenter, retrospective study between September to December 2019. Magnetic resonance imaging (MRI) diffusion-weighted images (DWIs), and the pathologic findings of 56 patients with glioma tumors (low grade = 28 and high grade = 28) were assessed to measure the ADC values in the tumor center, tumor edema, boundary area between tumor with normal tissue, and inside the healthy hemisphere. These values were compared between the two groups, and cut-off values were calculated using the receiver operating characteristic curve.

Results

We saw significant differences between the mean ADC values measured in the tumor center and edema between high- and low-grade tumors (p< 0.005). The ADC values in the boundary area between tumors with normal tissue and inside healthy hemisphere did not significantly differ in the groups. The ADC values at tumor center and edema were higher than 1.12 × 10^-3 mm²/s (sensitivity = 100% and specificity = 96.0%) and 1.15 × 10^-3 mm²/s (sensitivity = 75.0% and specificity = 64.0%), respectively, could be classified as low-grade tumors.

Conclusions

The ADC values from the MRI DWIs in the tumor center and edema could be used as an appropriate method for investigating the differences between low- and high-grade glioma tumors. The ADC values in the boundary area and healthy tissues had no diagnostic values in grading the glioma tumors.

Non-contrast MRI can accurately characterize adnexal masses: a retrospective study

Objective

To determine the accuracy of interpretation of a non-contrast MRI protocol in characterizing adnexal masses.

Methods and materials

Two hundred ninety-one patients (350 adnexal masses) who underwent gynecological MRI at our institution between the 1^st of January 2008 and the 31^st of December 2018 were reviewed. A random subset (102 patients with 121 masses) was chosen to evaluate the reproducibility and repeatability of readers’ assessments. Readers evaluated non-contrast MRI scans retrospectively, assigned a 5-point score for the risk of malignancy and gave a specific diagnosis. The reference standard for the diagnosis was histopathology or at least one-year imaging follow-up. Diagnostic accuracy of the non-contrast MRI score was calculated. Inter- and intra-reader agreement was analyzed with Cohen’s kappa statistics.

Results

There were 53/350 (15.1%) malignant lesions in the whole cohort and 20/121 (16.5%) malignant lesions in the random subset. Good agreement between readers was found for the non-contrast MRI score (к = 0.73, 95% confidence interval [CI] 0.58–0.86) whilst the intra-reader agreement was excellent (к = 0.81, 95% CI 0.70–0.88). The non-contrast MRI score value of ≥ 4 was associated with malignancy with a sensitivity of 84.9%, a specificity of 95.9%, an accuracy of 94.2% and a positive likelihood ratio of 21 (area under the receiver operating curve 0.93, 95% CI 0.90–0.96).

Conclusion

Adnexal mass characterization on MRI without the administration of contrast medium has a high accuracy and excellent inter- and intra-reader agreement. Our results suggest that non-contrast studies may offer a reasonable diagnostic alternative when the administration of intravenous contrast medium is not possible.

Key Points

• A non-contrast pelvic MRI protocol may allow the characterization of adnexal masses with high accuracy.

• The non-contrast MRI score may be used in clinical practice for differentiating benign from malignant adnexal lesions when the lack of intravenous contrast medium precludes analysis with the O–RADS MRI score.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-07737-9.

Radiomic Analysis of MRI Images is Instrumental to the Stratification of Ovarian Cysts

The imaging diagnosis of malignant ovarian cysts relies on their morphological features, which are not always specific to malignancy. The histological analysis of these cysts shows specific fluid characteristics, which cannot be assessed by conventional imaging techniques. This study investigates whether the texture-based radiomics analysis (TA) of magnetic resonance (MRI) images of the fluid content within ovarian cysts can function as a noninvasive tool in differentiating between benign and malignant lesions. Twenty-eight patients with benign (n = 15) and malignant (n = 13) ovarian cysts who underwent MRI examinations were retrospectively included. TA of the fluid component was undertaken on an axial T2-weighted sequence. A comparison of resulted parameters between benign and malignant groups was undertaken using univariate, multivariate, multiple regression, and receiver operating characteristics analyses, with the calculation of the area under the curve (AUC). The standard deviation of pixel intensity was identified as an independent predictor of malignant cysts (AUC = 0.738; sensitivity, 61.54%; specificity, 86.67%). The prediction model was able to identify malignant lesions with 84.62% sensitivity and 80% specificity (AUC = 0.841). TA of the fluid contained within the ovarian cysts can differentiate between malignant and benign lesions and potentially act as a noninvasive tool augmenting the imaging diagnosis of ovarian cystic lesions.

[Clinical, therapeutic and prognostic aspects of malignant germ cell tumors of the ovary: experience of 21 years old Tunisian]

Introduction

les tumeurs germinales malignes de l´ovaire (TGMO) sont des tumeurs ovariennes rares. Chaque type histologique peut avoir des particularités cliniques et thérapeutiques qu´il est important de connaître. L´objectif était de rapporter et analyser les particularités des données épidémiologiques, diagnostiques, anatomopathologiques, thérapeutiques et pronostiques des TGMO dans notre contexte tunisien.

Méthodes

notre étude est une enquête rétrospective descriptive et analytique réalisée aux services de Gynécologie-obstétrique du CHU FARHAT HACHED de Sousse sur une période de 21 ans colligeant tous les cas des patientes ayant été traitées pour TGMO.

Résultats

un nombre total de 30 dossiers a été éligible pour notre étude. L´âge moyen de nos patientes était de 22ans. La majorité des patientes étaient en période d´activité génitale. Le motif de consultation était représenté essentiellement par les douleurs abdomino-pelviennes suivie d´une augmentation du volume abdominal. L´échographie abdominopelvienne a été pratiquée chez 80% de nos patientes montrant un aspect suspect de malignité chez 100% d´entre elles. Pour nos patientes, 70% ont été abordées par laparotomie médiane vu le volume tumoral et 30% seulement par cœlioscopie. 76,7% ont eu un traitement conservateur. On a noté la prédominance de stade I alors qu´on n´a pas eu de cas en stade IV. La survie globale tout stade confondu était de 96,7% à 2ans et de 85,7% à 5ans et 75,8% à 10ans. Les facteurs pronostiques des TGMO isolés de notre série étaient le délai de consultation supérieur à 6mois, l´âge supérieur à 30ans, la taille tumorale supérieure à 20cm et le stade tumoral.

Conclusion

il serait plus intéressant de rassembler les autres cas de TGMO diagnostiqués au niveau des autres registres du cancer du pays afin d´établir un registre national des tumeurs rares de l´ovaire.

Bimodal magnetic resonance and optical imaging of extracellular matrix remodelling by orthotopic ovarian tumours

BACKGROUND

The extracellular matrix modulates the development of ovarian tumours. Currently, evaluation of the extracellular matrix in the ovary is limited to histological methods. Both magnetic resonance imaging (MRI) and two-photon microscopy (2PM) enable dynamic visualisation and quantification of fibrosis by endogenous contrast mechanisms: magnetisation transfer (MT) MRI and second-harmonic generation (SHG) 2PM, respectively.

METHODS

Here, we applied the MT-MRI protocol for longitudinal imaging of the stroma in orthotopic human ovarian cancer ES-2 xenograft model in CD1 athymic nude mice, and for orthotopically implanted ovarian PDX using a MR-compatible imaging window chamber implanted into NSG mice.

RESULTS

We observed differences between ECM deposition in ovarian and skin lesions, and heterogeneous collagen distribution in ES-2 lesions. An MR-compatible imaging window chamber enabled visual matching between T2 MRI maps of orthotopically implanted PDX grafts and anatomical images of their microenvironment acquired with a stereomicroscope and SHG-2PM intravital microscopy of the collagen. Bimodal MRI/2PM imaging allowed us to quantify the fibrosis within the same compartments, and demonstrated the consistent results across the modalities.

CONCLUSIONS

This work demonstrates a novel approach for measuring the stromal biomarkers in orthotopic ovarian tumours in mice, on both macroscopic and microscopic levels.

Characterization of Adnexal Masses Using Contrast-Enhanced Subharmonic Imaging: A Pilot Study

OBJECTIVES

This pilot study evaluated whether contrast-enhanced subharmonic imaging (SHI) could be used to characterize adnexal masses before surgical intervention.

METHODS

Ten women (with 12 lesions) scheduled for surgery of an ovarian mass underwent an SHI examination of their adnexal region using a modified LOGIQ E9 scanner (GE Healthcare, Waukesha, WI) with an endocavitary transducer, in which digital clips were acquired by pulse destruction-replenishment SHI across the lesions. Time-intensity curves were created offline to quantitatively evaluate SHI parameters (fractional tumor perfusion, peak contrast intensity, time to peak contrast enhancement, and area under the time-intensity curve), which were compared to pathologic characterizations of the lesions.

RESULTS

Of the 12 masses, 8 were benign, and 4 were malignant. A qualitative analysis of the SHI images by an experienced radiologist resulted in diagnostic accuracy of 70%, compared to 56% without contrast, whereas an inexperienced radiologist improved from 50% to 58% accuracy, demonstrating the benefit of SHI. A quantitative analysis of SHI parameters produced diagnostic accuracy as high as 81%. Peak contrast intensity was significantly greater in malignant than benign masses (mean ± SD, 0.109 ± 0.088 versus 0.046 ± 0.030 arbitrary units; P = .046). Malignant masses also showed significantly greater perfusion than benign masses (24.79% ± 25.34% versus 7.62% ± 6.50%; P = .045). When the radiologist reads were combined with the most predictive quantitative SHI parameter (percent perfusion), diagnostic accuracy improved to 84% for the experienced radiologist and 96% for the novice radiologist.

CONCLUSIONS

Results indicate that SHI for presurgical characterization of adnexal masses may improve the determination of malignancy and diagnostic accuracy, albeit based on a small sample size.

[Borderline Ovarian Tumours: CNGOF Guidelines for Clinical Practice - Imaging]

OBJECTIVE

To determine the place of imaging and the performance of different imaging techniques (transvaginal ultrasound with or without Doppler, scoring, CT, MRI) to differentiate benign tumour, borderline ovarian tumour (BOT) and malignant ovarian tumor. Differentiate the histological subtypes of BOT (serous, sero-mucinous, mucinous) and prediction in imaging of the possibility of conservative treatment.

METHODS

The research was carried out over the last 16 years using the terms "MeSH" based on the query of the Medline® database and supplemented by the review of references contained in the meta-analyzes, systematic reviews and original articles included.

RESULTS

Endo-vaginal and suprapubic ultrasonography is recommended for analysis of an ovarian mass (grade A). In the case of ultrasound by a referent, subjective analysis is the recommended technique (grade A). In case of echography by a non-referent, the use of "Simple Rules" is recommended (grade A) and should be best combined with subjective analysis to rejoin the performance of a sonographer refer (grade A). In cases of undetermined ovarian lesions in endovaginal ultrasound and suprapubic ultrasound, it is recommended to perform a pelvic MRI (grade A). The MRI protocol should include T2, T1, T1 sequences with fat saturation, diffusion, injected dynamics, and after gadolinium injection (grade B). To characterize an MRI-adnexal image, it is recommended to include a risk score for malignancy (ADNEX-MR/O-RADS) (grade C) in the report and to formulate an anatomopathological hypothesis (Grade C). The predictive signs of benignity in front of a cyst with endocystic vegetations are the low number, the small size, the presence of calcifications and the absence of Doppler flow in case of size greater than 10mm in echography (LP 4) and a curve of type 1 MRI (LP4). MRI is recommended for suspicious lesions of BOT in ultrasound (grade B) or indeterminate lesions in ultrasound (grade A). There is no data to support the usefulness of CT or PET-CT for BOT. Morphological criteria in ultrasound and MRI exist to differentiate BOT from invasive tumors regardless of grade (NP 2). Pelvic MRI is recommended to characterize a tumor suggestive of ultrasound BOT (grade C). No recommendations can be made about the use of combined ultrasound, biological, and menopausal status scores for the diagnosis of BOT. The diagnostic performance of imaging to detect peritoneal implants of BOT is not known. The assessment of the invasiveness of peritoneal implants of imaging BOT has not been evaluated. The association of macroscopic signs in MRI makes it possible to differentiate the different subtypes - serous, sero-mucinous and mucinous (intestinal type) - of BOT, despite the overlap of certain presentations (LP3). The analysis of macroscopic MRI signs must be performed to differentiate the different subtypes of TFO (grade C). No recommendation can be made on imaging prediction of the possibility of conservative BOT treatment.

The usefulness of diffusion-weighted MRI in the differentiation between focal uterine endometrial soft tissue lesions

Background

Several endometrial conditions may be challenging for radiologists due to the overlap of imaging features and variable endometrial pathologies. MRI with DWI is the most commonly used imaging technique for the diagnosis and characterization of endometrial focal lesions.

Results

The 50 studied lesions were classified according to their histopathological results into the benign group (28 lesions, 56%) and the malignant group (22 lesions, 44%). Conventional MRI could correctly diagnose 39 of the 50 lesions (22/28 benign and 17/22 malignant lesions), achieving a sensitivity of 77.27%, specificity of 78.56%, accuracy of 78%, predictive positive value (PPV) of 73.91%, and negative positive value (NPV) of 81.48%. By combining DWI and apparent diffusion coefficient (ADC) value mapping at a high b value (b = 1000) in MRI, we could correctly diagnose 47 of the 50 lesions (26/28 benign and 21/22 malignant lesions), with increased sensitivity (95.45%), specificity (92.86%), accuracy (94%), PPV (91.3%), and NPV (96%).

Conclusion

Combining DWI with ADC mapping at a high b value in pelvic MRI examination is valuable in differentiating endometrial focal lesions with increased diagnostic sensitivity, specificity, and accuracy.

Aim of the work

This study aimed to evaluate the role of DWI in the diagnosis and differential diagnosis of benign and malignant focal endometrial masses.

Apparent diffusion coefficients measured using different regions of interest in differentiating borderline from malignant ovarian tumors

Background

Apparent diffusion coefficients (ADCs) measured using different regions of interest (ROIs) are widely used in differentiating ovarian tumors.

Purpose

To evaluate the diagnostic performance of ADCs with different ROIs in differentiating borderline ovarian tumors (BOTs) from malignant ovarian tumors (MOTs).

Material and Methods

Thirty-five BOTs and 54 MOTs who underwent diffusion-weighted magnetic resonance imaging (MRI) were evaluated retrospectively. ADC values were independently measured using five ROI methods: round; rectangle; hot-spot; edge drawing; and five sample ROIs. The inter- and intraclass correlation coefficients (ICCs), one-way analysis of variance, receiver operating characteristic curve analysis, and unpaired t-tests were used to perform the statistical analyses.

Results

The measurement reproducibility of the minimum ADC and mean ADC values were good or excellent for BOTs and MOTs (ICC = 0.70–0.95). The minimum and mean ADC value by the edge drawing ROI were significantly higher than those of the other ROI methods (both P < 0.05). The area under the curve (AUC) of the minimum ADC value was less than that of the mean ADC value from the five ROI methods, whereas the AUCs of the mean ADC values from the round ROI and five sample ROIs were significantly larger than those of the other ROI methods ( P < 0.05). The minimum and mean ADC values from the five ROI methods showed significant differences between BOTs and MOTs (all P < 0.05).

Conclusion

The ROI shape influences the diagnostic performance of ADC value for differentiating BOTs from MOTs. The mean ADC values from the round ROI and five sample ROIs have better diagnostic efficiency.

An Unusual Ovarian Mucinous Borderline Tumor with a Large Solid Component

Herein, we report magnetic resonance imaging (MRI) findings of a mucinous borderline tumor of the ovary, which we observed as a mainly solid tumor with large solid components in the lower pelvic cavity. The appearance of ovarian epithelial tumors on imaging is often complex. Cystic to solid appearing masses may be observed, and they often resemble epithelial carcinoma. Due to mucinous or hemorrhage components of packed small or microcystic components, MRI depicts slightly high signal intensity on T1-weighted images and low signal intensity on T2-weighted images. Mucinous borderline tumor of the ovary with a large solid component is very rare, but it is clinically important to recognize the possibility of mucinous borderline tumor to avoid unnecessary surgical intervention.

Susceptibility Weighted With Quantitative Phase Magnetic Resonance Imaging in Differentiation of Various Stages of Hemorrhage and Calcification in Female Pelvic Pathologies: A Preliminary Study

BACKGROUND

The purposes of this study were to assess the value of phase for characterization of female pelvic lesions with hemorrhage in various stages and to differentiate them from calcified lesions at 3.0-T magnetic resonance imaging (MRI).

METHODS

Forty-four female patients with hemorrhagic (n = 37) or calcified (n = 7) pelvic pathology underwent conventional MRI including susceptibility-weighted imaging with phase information. Hemorrhagic lesions were grouped into acute, subacute, and chronic, and calcified lesions were detected on the basis of conventional imaging findings. Phase quantification of these hemorrhagic and calcified lesions was performed.

RESULTS

The phase values significantly differed (P < 0.001) among various stages of hemorrhage, as well as calcification (chronic hemorrhage, -65.09 ± 9.09 degrees; subacute hemorrhage, -11.41 ± 4.4 degrees; acute hemorrhage, -42.30 ± 5.20 degrees; and calcified lesions, 117.55 ± 12.93 degrees).

CONCLUSIONS

Quantitative phase imaging has the potential to differentiate various stages of hemorrhagic and calcified pathologies. This may add value to the conventional MRI in improved characterization of these entities in female pelvic pathologies.

The distribution of the apparent diffusion coefficient as an indicator of the response to chemotherapeutics in ovarian tumour xenografts

Diffusion-weighted magnetic resonance imaging (DW-MRI) was used to evaluate the effects of single-agent and combination treatment regimens in a spheroid-based animal model of ovarian cancer. Ovarian tumour xenografts grown in non-obese diabetic/severe-combined-immunodeficiency (NOD/SCID) mice were treated with carboplatin or paclitaxel, or combination carboplatin/paclitaxel chemotherapy regimens. After 4 weeks of treatment, tumours were extracted and underwent DW-MRI, mechanical testing, immunohistochemical and gene expression analyses. The distribution of the apparent diffusion coefficient (ADC) exhibited an upward shift as a result of each treatment regimen. The 99-th percentile of the ADC distribution (“maximum ADC”) exhibited a strong correlation with the tumour size (r² = 0.90) and with the inverse of the elastic modulus (r² = 0.96). Single-agent paclitaxel (n = 5) and combination carboplatin/paclitaxel (n = 2) treatment regimens were more effective in inducing changes in regions of higher cell density than single-agent carboplatin (n = 3) or the no-treatment control (n = 5). The maximum ADC was a good indicator of treatment-induced cell death and changes in the extracellular matrix (ECM). Comparative analysis of the tumours’ ADC distribution, mechanical properties and ECM constituents provides insights into the molecular and cellular response of the ovarian tumour xenografts to chemotherapy. Increased sample sizes are recommended for future studies. We propose experimental approaches to evaluation of the timeline of the tumour’s response to treatment.

Mucinous borderline ovarian tumor: a case report with diagnostic insights on ultrasound findings

Borderline ovarian tumors represent about 10% of all epithelial ovarian cancers, but in contrast to epithelial ovarian cancers, they constitute a group of tumors with a much better prognosis. An assessment of clinical presentation, physical examination, radiological and biochemical findings is necessary to tailor management strategies for patients with ovarian tumors. The article, which is based on a case report, describes different approaches for preoperative diagnosis as well as discusses approaches that might bring some insights on tumor histology. Furthermore, it raises a question about which imaging techniques should be proposed for a reliable diagnosis of borderline ovarian tumors to ensure safe surgery planning.

External validation of the MR imaging scoring system for the management of adnexal masses

OBJECTIVE

To investigate the prognostic value of ADNEX Magnetic Resonance Imaging Scoring in the preoperative management of adnexal masses.

STUDY DESIGN

We performed a retrospective study on patients who underwent surgery for an adnexal mass, with prior exploration by Magnetic Resonance Imaging (MRI), at the Gynecology Department of the Poissy Teaching Hospital between May 2012 and August 2014. MRI data were retrospectively read by radiologists, without knowledge of the histology, and classified according to the criteria of the ADNEX MR score. The radiological presumption of benign or malignant mass was compared with the final histological diagnosis. We calculated the sensitivity, specificity, positive and negative likelihood ratios and ROC curve of the ADNEX MR score with their 95% confidence intervals (95%CI).

RESULTS

One-hundred-and-forty-eight patients were included in the study of which 24 had malignant or borderline ovarian tumors. The proportion of malignant or borderline ovarian tumors in each class of the ADNEX MR score in our study was: ADNEX I: 0% (95%CI, 0-8); ADNEX II: 1.7% (95%CI, 0.04-8.9); ADNEX III: 7.7% (95%CI, 0.2-36); ADNEX IV: 57.1% (95%CI, 34.2-78.8) and ADNEX V: 100% (95%CI, 69.2-100). Thus, for an ADNEX MR score greater than or equal to 4, the sensitivity was 91.7% (95%CI, 73-99) and the specificity 92.7% (95%CI, 86.7-96.6) for the diagnosis of a malignant or borderline ovarian tumor. The area under the ROC curve was 0.92 (95% CI%, 0.86-0.98).

CONCLUSIONS

MRI, coupled with the use of the ADNEX MR scoring system, can accurately classify adnexal masses into low-risk (ADNEX MR score <4) or high-risk (ADNEX MR score ≥4) group, thereby allowing for appropriate preoperative counseling and planning for surgery.

MRI for discriminating metastatic ovarian tumors from primary epithelial ovarian cancers

AIMS

To find specific magnetic resonance imaging (MRI) features to differentiate metastatic ovarian tumors from primary epithelial ovarian cancers.

METHODS

Eleven cases with metastatic ovarian tumors and 26 cases with primary malignant epithelial ovarian cancers were retrospectively studied. All features such as patient characteristics, MRI findings and biomarkers were evaluated. The differences including laterality, configuration, uniformity of locules, diffusion weighted imaging (DWI) signal of solid components and enhancement of solid portions between metastatic ovarian tumors and primary epithelial ovarian cancers were compared by Fisher's exact test. Median age of patients, the maximum diameter of lesions and biomarkers were compared by the Mann-Whitney test.

RESULTS

Patients with metastatic ovarian tumors were younger than patients with primary epithelial ovarian cancers in the median age (P = 0.015). Patients with bilateral tumors in metastatic ovarian tumors were more than those of primary epithelial ovarian cancers (P = 0.032). The maximum diameter of lesions in metastatic ovarian tumors was smaller than that of primary epithelial ovarian cancers (P = 0.005). The locules in metastatic ovarian tumors were more uniform than those of primary epithelial ovarian cancers (P = 0.024). The enhancement of solid portions in metastatic ovarian tumors showed more moderate than that of primary epithelial ovarian cancers (P = 0.037). There was no statistically significant difference between the two groups in configuration, DWI signal of solid components and ascites. Biomarkers such as CA125 and human epididymis protein 4 (HE4) in metastatic ovarian tumors showed less elevated than that of primary epithelial ovarian cancers.

CONCLUSIONS

Significant differences between metastatic ovarian tumors and primary epithelial ovarian cancers were found in the median age of patients, laterality, the maximum diameter of lesions, uniformity of locules, enhancement patterns of solid portions and biomarkers. Metastatic ovarian tumors usually presented in the younger patients, smaller-sized, more bilateral lesions, more uniform of locules, more moderate enhancement of solid portions, and less elevated levels of CA125 and HE4 than those of primary epithelial ovarian cancers.

Primary fallopian tube carcinoma: correlation between magnetic resonance and diffuse weighted imaging characteristics and histopathologic findings

OBJECTIVE

The aim of this study was to investigate the magnetic resonance (MR) and diffusion-weighted (DW) imaging characteristics of primary fallopian tube carcinoma (PFTC).

METHODS

The clinical, MR, and DW imaging characteristics and pathologic findings of 23 patients with 27 tumors were studied retrospectively. The MR and DW imaging appearance of tumors including laterality, size and shape, architecture, signal intensity, apparent diffusion coefficient (ADC) value, enhancement pattern, hydrosalpinx, and intrauterine fluid collection were evaluated and correlated with pathologic findings.

RESULTS

Histopathologically, all 27 tumors were serous carcinoma with a unilateral tumor in 19 patients and bilateral tumors in 4 patients. Thirteen patients (57%) with PFTC were misdiagnosed preoperatively, 10 of which as epithelial ovarian carcinoma. The mean (SD) largest diameter was 61 (7) mm. The tumor shape was fusiform, sausagelike, or serpentine in 19 patients (70%) and nodular or irregular in 8 patients (30%). Twenty (74%) of the 27 tumors were solid, and 7 (26%) were cystic-solid. The solid components showed hypointensity to isointensity on T1-weighted imaging, and isointensity to slight hyperintensity on T2-weighted imaging. There were obvious hyperintensity on DW imaging; obvious hypointensity on ADC maps with a mean (SD) ADC value of 0.79 (0.22) × 10 mm; and mild (8/27, 30%), moderate (13/27, 48%), and marked (6/27, 22%) enhancement on contrast-enhanced imaging. Ipsilateral hydrosalpinx, intrauterine fluid collection, and ascites were found in 14 tumors (52%) and 7 (30%) and 5 (22%) patients, respectively.

CONCLUSIONS

The PFTC has some characteristic MR imaging features. The DW imaging, ADC maps, and ADC values are helpful for the detection and differentiation of PFTC from other pelvic masses.

Correlation of Pelvic Magnetic Resonance Imaging Diagnosis With Pathology for Indeterminate Adnexal Masses

Objectives

The aim of this study was to determine the accuracy of pelvic magnetic resonance imaging (MRI) diagnoses compared with the final pathology diagnoses for a series of women with indeterminate adnexal masses.

Materials and Methods

We performed a retrospective cohort study of women who underwent pelvic MRI with a diagnosis of an adnexal mass between June 2009 and 2010 after indeterminate ultrasound at our tertiary care institution. Chart abstraction was performed for demographic information and radiologic interpretations (benign or malignant) and favored a specific histologic subtype on MRI reports. The radiologic diagnoses were compared with the diagnoses by surgical pathology.

Results

Data from 237 female patients who underwent pelvic MRI were included, and 41.35% underwent surgical intervention for the adnexal mass. Pelvic MRI (n = 88) was determined to have a sensitivity of 95.0% and specificity of 94.1%. The predicted specific histologic subtype by MRI (n = 84) was accurate in 56 (98.25%) of 57 women with an anticipated benign diagnosis and in 23 (85.19%) of 27 women with an anticipated malignancy. The agreement between a benign diagnosis from MRI and benign final surgical pathology was 0.85 (95% confidence interval, 0.716–0.976).

Conclusions

In our tertiary care center, MRI is used to further characterize indeterminate adnexal masses and can accurately differentiate benign versus malignant adnexal masses. The diagnosis on MRI was highly correlative with the final histopathology. The majority of the cohort (59%) were able to be managed expectantly based on reassuring results of the MRI. Magnetic resonance imaging offered diagnostic value, more detailed patient counseling, appropriate subspecialty referral, and surgical planning, as well as reassurance to pursue conservative management of benign masses by MRI.

Practical approach to MRI of female pelvic masses

OBJECTIVE

Female pelvic masses have a broad differential diagnosis, including benign and malignant neoplasms and nonneoplastic entities.

CONCLUSION

By using a systematic approach to the evaluation of a complex pelvic mass, including incorporating the clinical and surgical history, and by using multiparametric MRI to identify the anatomic origin, morphologic features, and tissue composition of a mass, a short meaningful differential diagnosis or definitive diagnosis can often be established.

Diffusion-weighted MR imaging for differentiating borderline from malignant epithelial tumours of the ovary: pathological correlation

OBJECTIVES

To investigate diffusion-weighted (DW) magnetic resonance (MR) imaging for differentiating borderline from malignant epithelial tumours of the ovary.

METHODS

This retrospective study included 60 borderline epithelial ovarian tumours (BEOTs) in 48 patients and 65 malignant epithelial ovarian tumours (MEOTs) in 54 patients. DW imaging as well as conventional MR imaging was performed. Signal intensity on DW imaging was assessed and apparent diffusion coefficient (ADC) value was measured. The results were correlated with histopathology and cell density.

RESULTS

The majority of MEOTs showed high signal intensity on DW imaging, whereas most BEOTs showed low or moderate signal intensity (P = 0.000). The mean ADC value of the solid components in BEOTs (1.562 ± 0.346 × 10(-3) mm(2)/s) was significantly higher than in MEOTs (0.841 ± 0.209 × 10(-3) mm(2)/s). A threshold value of 1.039 × 10(-3) mm(2)/s permitted the distinction with a sensitivity of 97.0%, a specificity of 92.2% and an accuracy of 96.4%. There was an inverse correlation between ADC value and cell density (r = -0.609; P = 0.0000) which was significantly lower in BEOTs than in MEOTs.

CONCLUSIONS

DW imaging is useful for differentiating borderline from malignant epithelial tumours of the ovary.

KEY POINTS

DW MR imaging is useful for differentiating BEOTs from MEOTs. Patients with BEOTs are treated differently from patients with MEOTs. Conservative fertility-sparing laparoscopic surgery can be performed in patients with BEOTs. BEOTs often affect young women of childbearing age.

MRI in differentiating ovarian borderline from benign mucinous cystadenoma: pathological correlation

PURPOSE

To investigate MRI in differentiating borderline mucinous cystadenoma (MC) from benign MC of the ovary.

MATERIALS AND METHODS

We studied MR images of 26 benign MCs and 24 borderline MCs of the ovary. The following MRI features of tumors were evaluated and compared between two groups: laterality, shape, size, loculation, signal intensity of the fluid, thickness of the septation and the wall, and vegetations. The results of the MRI were then compared with the pathological findings.

RESULTS

Honeycomb loculi, high signal intensity on T1WI, and low signal intensity on T2WI of the intracystic content, thickened septation or wall (≥5 mm), and vegetations (≥5 mm) were significantly more common in borderline MC than in benign MC with the sensitivity and specificity of identifying borderline MC of 50.0% and 80.8%, 41.7% and 96.2%, 45.8% and 96.2%, and 62.5% and 96.2%, respectively. The presence of any one of the following features-honeycomb loculi with a low signal intensity on T2WI, thickened septation or wall (≥5 mm), and vegetations (≥5 mm)-yielded the sensitivity, specificity, and accuracy of identifying borderline MC of 91.7%, 92.3%, and 92.0%, respectively.

CONCLUSION

MRI has the ability to accurately demonstrate the morphological characteristics of ovarian MC and reliably differentiate borderline MC from benign MC.

Evaluation of primary adnexal masses by 3T MRI: categorization with conventional MR imaging and diffusion-weighted imaging

Background

To investigate the 3.0-Tesla (3 T) magnetic resonance imaging (MRI) characteristics of primary adnexal lesions for discriminating benign from malignant lesions.

Methods

One hundred thirty-nine patients with pathologically proven primary adnexal masses referred for 3 T MRI assessment preoperatively were included. Baseline characteristics, components, and conventional MRI and diffusion-weighted imaging (DWI-MRI) signals were recorded and compared.

Results

There were 22 ovarian cysts, 33 endometriomas, 43 benign tumors and 42 malignant tumors. When ovarian cyst and endometrioma were excluded, there were no significant differences in patients’ age between benign and malignant tumor (P = 0.235). There were no significant differences (P = 0.606) in the conventional MRI signals and significant difference (P = 0.008) in DWI-MRI signal between the non-malignant and malignant lesions. There was a significant difference (P = 0.000) in the apparent diffusion coefficient values (ADCs) between the non-malignant and malignant lesions.

Conclusions

3 T MRI categorized the characteristics of primary adnexal lesions. Conventional MRI signals were not useful for characterizing between benign and malignant lesions. DWI-MRI and ADCs were helpful for distinguishing malignant from benign ovarian lesions.

Diagnostic accuracy of diffusion-weighted imaging with conventional MR imaging for differentiating complex solid and cystic ovarian tumors at 1.5T

Background

Preoperative characterization of complex solid and cystic adnexal masses is crucial for informing patients about possible surgical strategies. Our study aims to determine the usefulness of apparent diffusion coefficients (ADC) for characterizing complex solid and cystic adnexal masses.

Methods

One-hundred and 91 patients underwent diffusion-weighted (DW) magnetic resonance (MR) imaging of 202 ovarian masses. The mean ADC value of the solid components was measured and assessed for each ovarian mass. Differences in ADC between ovarian masses were tested using the Student’s t-test. The receiver operating characteristic (ROC) was used to assess the ability of ADC to differentiate between benign and malignant complex adnexal masses.

Results

Eighty-five patients were premenopausal, and 106 were postmenopausal. Seventy-four of the 202 ovarian masses were benign and 128 were malignant. There was a significant difference between the mean ADC values of benign and malignant ovarian masses (p < 0.05). However, there were no significant differences in ADC values between fibrothecomas, Brenner tumors and malignant ovarian masses. The ROC analysis indicated that a cutoff ADC value of 1.20 x10^-3 mm²/s may be the optimal one for differentiating between benign and malignant tumors.

Conclusions

A high signal intensity within the solid component on T2WI was less frequently in benign than in malignant adnexal masses. The combination of DW imaging with ADC value measurements and T2-weighted signal characteristics of solid components is useful for differentiating between benign and malignant ovarian masses.

Is MRI a useful tool to distinguish between serous and mucinous borderline ovarian tumours?

AIM

To analyse the morphological magnetic resonance imaging (MRI) features of borderline ovarian tumours (BOT) and to evaluate whether MRI can be used to distinguish serous from mucinous subtypes.

MATERIALS AND METHODS

A retrospective study of 72 patients who underwent BOT resection was undertaken. MRI images were reviewed blindly by two radiologists to assess MRI features: size, tumour type, grouped and irregular thickened septa, number of septa, loculi of different signal intensity, vegetations, solid portion, signal intensity of vegetations, normal ovarian parenchyma, and pelvic ascites. Statistical analysis was performed using Mann-Whitney and Fisher's exact tests. Logistic regression analysis was used to assess the predictive value of the MRI findings for histological subtypes.

RESULTS

At histology, there were 33 serous BOT (SBOT) and 39 mucinous BOT (MBOT). Predictive MRI criteria for SBOT were bilaterality, predominantly solid tumour, and the presence of vegetations, especially exophytic or with a high T2 signal (p < 0.01), whereas predictive MRI criteria for MBOT were multilocularity, number of septa, loculi of different signal intensity, and grouped and irregular thickened septa (p < 0.01). Using multivariate analysis, vegetations were independently associated with SBOT [odds ratio (OR) = 29.5] and multilocularity with MBOT (OR = 3.9).

CONCLUSION

Vegetations and multilocularity are two independent MRI features that can help to distinguish between SBOT and MBOT.

Diffusion-weighted MRI: a useful technique to discriminate benign versus malignant ovarian surface epithelial tumors with solid and cystic components

PURPOSE

To evaluate differences in apparent diffusion coefficient (ADC) values for the solid component of benign and malignant ovarian surface epithelial tumors with the goal of differentiating benign versus malignant ovarian tumors preoperatively.

MATERIALS AND METHODS

A total of 127 patients with 131 pelvic masses identified by ultrasound between January 2006 and January 2011 were enrolled in this study. 46 patients were diagnosed with benign tumors, and 85 patients were diagnosed with malignant pathologies. For all of the patients, routine spin-echo MRI and diffusion-weighted imaging were performed. ADC values were determined for all of the masses, and the mean ADC values for the benign and malignant tumors were analyzed using Student's t test. A P value <0.05 was considered statistically significant.

RESULTS

Mean ADC values associated with malignant ovarian surface epithelial tumors were significantly lower than the mean ADC values of the benign tumors. In addition, the range of ADC values associated with a 95% confidence interval did not overlap between the two groups. ROC analysis indicated that a cutoff ADC value of 1.25 × 10(-3) mm(2)/s was associated with 90.1% sensitivity and 89.9% specificity.

CONCLUSION

ADC values determined from 1.5 T MR DWI of benign and malignant ovarian masses were found to be significantly different.

Pelvic tumors with normal-appearing shapes of ovaries and uterus presenting as an emergency (Review)

Abdominal pain with an associated pelvic mass is a common problem in everyday practice. Concerns about ectopic pregnancy, torsion of an enlarged ovary or malignancy usually dominate the diagnostic evaluation. On physical and imaging examination, when a palpable painful mass is present in the pelvis and the two ovaries and uterus are detected in their normal anatomical locations, the content and origin of the lesions may be significant in narrowing the pre-operative differential diagnosis. Thus, the emergent pelvic indications discussed in this review should be considered. The causes of acute abdominal pain are few in number and therefore an accurate diagnosis may be most frequently made at the time of exploratory laparotomy.

Apparent diffusion coefficient measurements in the differentiation between benign and malignant lesions: a systematic review

Objectives

To systematically review the value of apparent diffusion coefficient (ADC) measurement in the differentiation between benign and malignant lesions.

Methods

A systematic search of the Medline/Pubmed and Embase databases revealed 109 relevant studies. Quality of these articles was assessed using the Quality Assessment of the Studies of Diagnostic Accuracy Included in Systematic Reviews (QUADAS) criteria. Reported ADC values of benign and malignant lesions were compared per organ.

Results

The mean quality score of the reviewed articles was 50%. Comparison of ADC values showed marked variation among studies and between benign and malignant lesions in various organs. In several organs, such as breast, liver, and uterus, ADC values discriminated well between benign and malignant lesions. In other organs, such as the salivary glands, thyroid, and pancreas, ADCs were not significantly different between benign and malignant lesions.

Conclusion

The potential utility of ADC measurement for the characterisation of tumours differs per organ. Future well-designed studies are required before ADC measurements can be recommended for the differentiation of benign and malignant lesions. These future studies should use standardised acquisition protocols and provide complete reporting of study methods, to facilitate comparison of results and clinical implementation of ADC measurement for tumour characterisation.

Electronic supplementary material

The online version of this article (doi:10.1007/s13244-012-0175-y) contains supplementary material, which is available to authorized users.

Early detection of ovarian cancer with conventional and contrast-enhanced transvaginal sonography: recent advances and potential improvements

Recently, there have been several major technical advances in the sonographic diagnosis of ovarian cancer in its early stages. These include improved assessment of tumor morphology with transvaginal sonography (TVS), and detection and characterization of tumor neovascularity with transvaginal color Doppler sonography (TV-CDS) and contrast-enhanced transvaginal sonography (CE-TVS). This paper will discuss and illustrate these improvements and describe how they enhance detection of early-stage ovarian cancer. Our initial experience with parametric mapping of CE-TVS will also be mentioned.

Benign and Suspicious Ovarian Masses-MR Imaging Criteria for Characterization: Pictorial Review

Ovarian masses present a special diagnostic challenge when imaging findings cannot be categorized into benign or malignant pathology. Ultrasonography (US), Computed Tomography (CT), and Magnetic Resonance Imaging (MRI) are currently used to evaluate ovarian tumors. US is the first-line imaging investigation for suspected adnexal masses. Color Doppler US helps the diagnosis identifying vascularized components within the mass. CT is commonly performed in preoperative evaluation of a suspected ovarian malignancy, but it exposes patients to radiation. When US findings are nondiagnostic or equivocal, MRI can be a valuable problem solving tool, useful to give also surgical planning information. MRI is well known to provide accurate information about hemorrhage, fat, and collagen. It is able to identify different types of tissue contained in pelvic masses, distinguishing benign from malignant ovarian tumors. The knowledge of clinical syndromes and MRI features of these conditions is crucial in establishing an accurate diagnosis and determining appropriate treatment. The purpose of this paper is to illustrate MRI findings in neoplastic and non-neoplastic ovarian masses, which were assessed into three groups: cystic, solid, and solid/cystic lesions. MRI criteria for the correct diagnosis and characteristics for differentiating benign from malignant conditions are shown in this paper.

Spectrum of mucin-producing neoplastic conditions of the abdomen and pelvis: Cross-sectional imaging evaluation

Various mucin-producing neoplasms originate in different abdominal and pelvic organs. Mucinous neoplasms differ from non-mucinous neoplasms because of the differences in clinical outcome and imaging appearance. Mucinous carcinoma, in which at least 50% of the tumor is composed of large pools of extracellular mucin and columns of malignant cells, is associated with a worse prognosis. Signet ring cell carcinoma is characterized by large intracytoplasmic mucin vacuoles that expand in the malignant cells with the nucleus displaced to the periphery. Its prognosis is also generally poor. In contrast, intraductal papillary mucinous neoplasm of the bile duct and pancreas, which is characterized by proliferation of ductal epithelium and variable mucin production, has a better prognosis than other malignancies in the pancreaticobiliary tree. Imaging modalities play a critical role in differentiating mucinous from non-mucinous neoplasms. Due to high water content, mucin has a similar appearance to water on ultrasound (US), computed tomography (CT), and magnetic resonance imaging, except when thick and proteinaceous, and then it tends to be hypoechoic with fine internal echoes or have complex echogenicity on US, hyperdense on CT, and hyperintense on T1- and hypointense on T2-weighted images, compared to water. Therefore, knowledge of characteristic mucin imaging features is helpful to diagnose various mucin-producing neoplastic conditions and to facilitate appropriate treatment.

Interest of diffusion-weighted echo-planar MR imaging and apparent diffusion coefficient mapping in gynecological malignancies: a review

Magnetic resonance imaging (MRI) remains the standard modality for the local staging of gynecological malignancies but it has several limitations, particularly for lymph node staging or evaluating peritoneal carcinomatosis. Consequently, there has been a growing interest in functional imaging modalities. Based on molecular diffusion, diffusion-weighted imaging (DWI) is a unique, noninvasive modality that provides excellent tissue contrast and was shown to improve the radiological diagnosis of malignant tumors. Using quantitative apparent diffusion coefficient (ADC) measurement of DWI provides a new tool for better distinguishing malignant tissues from benign tumors. The aim of the present review is to report on the results of DWI for the assessment of patients with gynecological malignancies. An analysis of the literature suggests that DWI studies would improve the diagnosis of cervical and endometrial tumors. It may also improve the assessment of tumor extension in patients with peritoneal carcinomatosis from gynecological malignancies. However, since the signal intensity of some cancers can range from high intensity to low intensity, a degree of uncertainty was demonstrated due to the proximity of the normal uterine myometrium and ovaries. Interestingly, there is also evidence that ADC might improve the follow-up and monitoring of patients who receive anticancer therapies, including chemotherapy or radiation therapy.

Malignant transformation of an endometriotic cyst: MDCT and MR findings

Malignant transformation is a rare complication of endometriosis. MR criteria for diagnosis include the presence of soft-tissue components, enhancement after contrast material administration in an endometriotic cyst. We present the multidetector CT and MR imaging findings in a case of an incidentally found endometrioid adenocarcinoma in a left-sided ovarian endometrioma, occurring in a 30-year old woman. MR imaging enabled the correct preoperative characterization of the lesion, by depicting a soft-tissue element, with strong and early enhancement after gadolinium administration. The same area had high signal intensity on diffusion-weighted images and low apparent diffusion coefficient values due to restricted diffusion, findings also strongly suggestive of malignancy.

Diffusion-weighted magnetic resonance imaging of ovarian tumors: differentiation of benign and malignant solid components of ovarian masses

OBJECTIVE

We evaluated the feasibility of diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) measurement in differentiating benign and malignant ovarian tumors.

METHODS

Surgically proven 49 ovarian tumors (39 malignant/borderline malignant and 10 benign) were examined.

RESULTS

The solid portion of all 39 malignant tumors showed homogeneous or heterogeneous high intensity on DWI, whereas only 3 of the 10 benign tumors (3 thecomas) showed high intensity. The mean (SD) ADC value in the 39 malignant tumors (1.03 [0.19]) was significantly lower than that in 10 benign tumors (1.38 [0.30]). A relatively low ADC (1.08-1.20) in the 3 thecomas may reflect their abundant cellular nature, and the presence of low intensity on T2-weighted images was suggestive for benign fibrous tumor.

CONCLUSIONS

Low intensity on DWI with high ADC may suggest benign lesions; however, it may be occasionally difficult to differentiate benign and malignant lesions only on the basis of DWI.