Value of 3.0 T diffusion-weighted imaging in discriminating thecoma and fibrothecoma from other adnexal solid masses

A Case Report of Comprehensive Diagnostic Approach on a Complex Left Adnexal Mass in a Young Female: Endometrioma or Complicated Ovarian Serous Cystadenofibroma

This case report presents a young female who was clinically, radiologically, and intraoperatively misdiagnosed as an ovarian endometrioma and was only diagnosed by histopathological biopsy as complicated serous cystadenofibroma, a rare benign tumor composed of both glandular and fibrous tissue. The diagnosis of adenofibroma typically involves a combination of imaging studies, such as ultrasound or magnetic resonance imaging (MRI) scan, and a histopathological biopsy to confirm the presence of the tumor. This case underscores the significance of utilizing various diagnostic methods and histopathological biopsies to diagnose and treat complex adnexal masses in females accurately.

Magnetic resonance imaging findings of a case with Wolffian tumor and related literature review

Background

Wolffian tumors in females are rare gynecological neoplasms, with fewer than 100 cases reported. Existing literature primarily focuses on the pathology, and reports involving imaging are limited.

Objective

This study presents a case of Wolffian tumor, emphasizing its magnetic resonance imaging (MRI) characteristics to enhance preoperative diagnostic accuracy.

Case report

A 56-year-old woman presented with a year-long history of irregular vaginal bleeding. MRI revealed a solid mass in the right adnexal region. On T2-weighted images, the mass exhibited slightly elevated signal intensity with a distinctive low-signal intensity rim. Diffusion-weighted imaging displayed markedly increased signal intensity, and the contrast enhancement was moderate. The patient underwent laparoscopic right adnexectomy and received a Wolffian tumor diagnosis. No recurrence was observed during a 6-month follow-up.

Conclusions

Wolffian tumors exhibit distinctive MRI presentations. Notably, the prominent low-signal intensity rim on MRI may aid in accurate preoperative tumor diagnosis.

MR imaging findings of ovarian lymphoma: differentiation from other solid ovarian tumors

PURPOSE

To evaluate magnetic resonance imaging (MRI) findings for distinguishing ovarian lymphomas from other solid ovarian tumors.

METHODS

This retrospective multicenter study included 14 women (median age, 46.5 years; range, 26-81 years) with surgically proven ovarian lymphoma and 28 women with solid ovarian tumors other than lymphoma. We conducted a subjective image analysis of factors including laterality, shape, composition, T2 signal intensity (SI), heterogeneity, diffusion restriction, enhancement, and presence of peripheral follicles. A generalized estimating equation was used to identify MRI findings that could be used to distinguish ovarian lymphomas from other solid ovarian tumors. Diagnostic performance of the identified MRI findings was assessed using the area under the receiver-operating characteristic curve (AUC).

RESULTS

Ovarian lymphoma more frequently showed homogeneous high SI on T2-weighted imaging (81.8% vs. 19.4%, P < 0.001) and peripheral ovarian follicles (40.9% vs. 8.3%, P = 0.01) than other ovarian solid tumors did. Bilaterality, shape, size, diffusion restriction, and enhancement did not differ between the two groups (P > 0.05 for all). Homogeneous high SI on T2-weighted imaging was the only independent MRI finding (OR = 15.19; 95% CI 3.15-73.33; P = 0.001) in the multivariable analysis. Homogeneous high SI on T2-weighted imaging yielded an AUC of 0.82 with a sensitivity of 81.8% and specificity of 80.6% in distinguishing ovarian lymphomas from other solid ovarian tumors.

CONCLUSION

Homogeneous high signal intensity on T2-weighted imaging was helpful in distinguishing ovarian lymphomas from other solid ovarian tumors. Peripheral ovarian follicles might be an additional clue that suggests a diagnosis of ovarian lymphoma.

Manifestations of Ovarian Cancer in Relation to Other Pelvic Diseases by MRI

Imaging plays a pivotal role in the diagnostic approach of women with suspected ovarian cancer. MRI is widely used for preoperative characterization and risk stratification of adnexal masses. While epithelial ovarian cancer (EOC) has typical findings on MRI; there are several benign and malignant pelvic conditions that may mimic its appearance on imaging. Knowledge of the origin and imaging characteristics of a pelvic mass will help radiologists diagnose ovarian cancer promptly and accurately. Finally, in special subgroups, including adolescents and gravid population, the prevalence of various ovarian tumors differs from that of the general population and there are conditions which uniquely manifest during these periods of life.

Fibrothecoma of broad ligament with minor sex cord elements: Case report and brief literature review

RATIONALE

Sex cord-stromal tumors are always found in ovary, but the occurrence of this kind of tumor at extraovarian locations is extremely rare. Up to now, the case concerning fibrothecoma of broad ligament with minor sex cord elements has not been reported, and it is extremely challenging to diagnose before surgery. In this case report, we summarized pathogenesis, clinical features, laboratory finding, imaging studies, pathology, and therapeutic schedule of this tumor, with the aim of raising awareness and attention to this type of disease.

PATIENT CONCERNS

A 45-year-old Chinese woman was referred to our department with intermittent lower abdominal pain for about 6 years. On examination, both ultrasonography and computed tomography revealed she had a right adnexal mass.

DIAGNOSIS

Based on the results of histology and immunohistochemistry, the final diagnosis was confirmed as fibrothecoma of broad ligament with minor sex cord elements.

INTERVENTIONS

This patient underwent laparoscopic unilateral salpingo-oophorectomy with excision of the neoplasm.

OUTCOMES

Eleven days post-treatment, the patient complained that the symptoms of abdominal pain was disappeared. There is no evidence of disease recurrence 5 years after laparoscopic surgery according to the consequences of radiologic examination.

CONCLUSION

The natural history of this kind of tumor is uncertain. Although main treatment of this neoplasm might be surgical resection and good prognosis can be achieved, we believe that long-time follow-up is extremely important in all patients diagnosed as fibrothecoma of broad ligament with minor sex cord. Laparoscopic unilateral salpingo-oophorectomy with excision of the tumor should be recommended to these patients.

Utility of the Diffusion Weighted Sequence in Gynecological Imaging: Review Article

Simple Summary

Diffusion weighted imaging (DWI) is a magnetic resonance imaging sequence with diverse clinical applications in malignant and nonmalignant gynecological conditions. It provides vital supplemental information in the diagnosis and management of various gynecological conditions. Radiologists should be aware of fundamental concepts, clinical applications and pitfalls of DWI. Additionally we briefly discuss potential scope of newer advanced techniques based on DWI including diffusion tensor imaging and diffusion-weighted whole-body imaging with background signal suppression.

Abstract

Functional imaging with diffusion-weighted imaging (DWI) is a complementary tool to conventional diagnostic magnetic resonance imaging sequences. It is being increasingly investigated to predict tumor response and assess tumor recurrence. We elucidate the specific technical modifications of DWI preferred for gynecological imaging, including the different b-values and planes for image acquisition. Additionally, we discuss the problems and potential pitfalls encountered during DWI interpretation and ways to overcome them. DWI has a wide range of clinical applications in malignant and non-malignant gynecological conditions. It provides supplemental information helpful in diagnosing and managing tubo-ovarian abscess, uterine fibroids, endometriosis, adnexal torsion, and dermoid. Similarly, DWI has diverse applications in gynecological oncology in diagnosis, staging, detection of recurrent disease, and tumor response assessment. Quantitative evaluation with apparent diffusion coefficient (ADC) measurement is being increasingly evaluated for correlation with various tumor parameters in managing gynecological malignancies aiding in preoperative treatment planning. Newer advanced DWI techniques of diffusion tensor imaging (DTI) and whole body DWI with background suppression (DWIBS) and their potential uses in pelvic nerve mapping, preoperative planning, and fertility-preserving surgeries are briefly discussed.

The Value of MRI Findings Combined With Texture Analysis in the Differential Diagnosis of Primary Ovarian Granulosa Cell Tumors and Ovarian Thecoma-Fibrothecoma

Objective

This study aims to explore the value of magnetic resonance imaging (MRI) and texture analysis (TA) in the differential diagnosis of ovarian granulosa cell tumors (OGCTs) and thecoma-fibrothecoma (OTCA–FTCA).

Methods

The preoperative MRI data of 32 patients with OTCA–FTCA and 14 patients with OGCTs, confirmed by pathological examination between June 2013 and August 2020, were retrospectively analyzed. The texture data of three-dimensional MRI scans based on T2-weighted imaging and clinical and conventional MRI features were analyzed and compared between tumor types. The Mann–Whitney U-test, χ² test/Fisher exact test, and multivariate logistic regression analysis were used to identify differences between the OTCA–FTCA and OGCTs groups. A regression model was established by using binary logistic regression analysis, and receiver operating characteristic curve analysis was carried out to evaluate diagnostic efficiency.

Results

A multivariate analysis of the imaging-based features combined with TA revealed that intratumoral hemorrhage (OR = 0.037), log-sigma-20mm-3D_glszm_SmallAreaEmphasis (OR = 4.40), and log-sigma-2-0mm-3D_glszm_SmallAreaHighGrayLevelEmphasis (OR = 1.034) were independent features for discriminating between OGCTs and OTCA–FTCA (P < 0.05). An imaging-based diagnosis model, TA-based model, and combination model were established. The areas under the curve of the three models in predicting OGCTs and OTCA–FTCA were 0.935, 0.944, and 0.969, respectively; the sensitivities were 93.75, 93.75, and 96.87%, respectively; and the specificities were 85.71, 92.86, and 92.86%, respectively. The DeLong test indicated that the combination model had the highest predictive efficiency (P < 0.05), with no significant difference among the three models in differentiating between OGCTs and OTCA–FTCA (P > 0.05).

Conclusions

Compared with OTCA–FTCA, intratumoral hemorrhage may be characteristic MR imaging features with OGCTs. Texture features can reflect the microheterogeneity of OGCTs and OTCA–FTCA. MRI signs and texture features can help differentiate between OGCTs and OTCA–FTCA and provide a more comprehensive and accurate basis for clinical treatment.

Comprehensive review of imaging features of sex cord-stromal tumors of the ovary

Sex cord-stromal tumors of the ovary (SCST) are uncommon ovarian tumors arising from sex cord and/or stromal cells of the ovaries. They may be nonfunctional and asymptomatic or functional presenting with hyperestrogenic, hyperandrogenic or cushingoid symptoms. They present in a wide age group of women, mostly in early stages and follow a nonaggressive clinical course after surgical resection. They differ from more prevalent epithelial ovarian tumors which tend to present in older women in advanced stages with poor prognosis. Some of SCSTs are associated with clinical syndromes. We will review imaging features on ultrasound, computed tomography and magnetic resonance imaging, epidemiology and clinical presentations of these tumors.

Ovarian sex cord-stromal tumors: an update on clinical features, molecular changes, and management

Sex cord stromal-tumors are rare tumors of the ovary that include numerous tumor subtypes of variable histological features and biological behavior. Surgery is the main therapeutic modality for the management of these tumors, while chemotherapy and hormonal therapy may be used in some patients with progressive and recurrent tumors. Several studies investigated molecular changes in the different tumor types. Understanding molecular changes underlying the development and progression of sex cord-stromal tumors provides valuable information for diagnostic and prognostic biomarkers and potential therapeutic targets for these tumors. In this review, we provide an update on the clinical presentation, molecular changes, and management of sex cord-stromal tumors.

A presentation of ovarian fibrothecoma in a middle-aged female with recurrent massive ascites and postmenopausal bleeding: A case report

Fibrothecomas are mostly benign ovarian tumors. We describe a rare case of fibrothecoma in a 59-year-old woman with a history of recurrent massive ascites and postmenopausal bleeding. Over 2 years she has undergone more than 50 paracenteses with 8–11 L withdrawn each time. She presented with a newly diagnosed pelvic mass and bilateral hydrosalpinges demonstrated on ultrasound and were confirmed with computed tomography. The pelvic magnetic resonance imaging showed a large complex cystic mass arising from the left ovary measuring 16.6 × 12.1 × 8.6 cm³ with an area of irregular mural enhancement. The patient underwent left salpingo-oophorectomy with benign frozen section results. The final pathology was consistent with cystic degeneration of fibrothecoma

Diagnostic Performance of MR Imaging-based Features and Texture Analysis in the Differential Diagnosis of Ovarian Thecomas/Fibrothecomas and Uterine Fibroids in the Adnexal Area

RATIONALE AND OBJECTIVES

To investigate the value of MRI-based features and texture analysis (TA) in the differential diagnosis between ovarian thecomas/fibrothecomas (OTCA/f-TCAs) and uterine fibroids in the adnexal area (UF-iaas).

MATERIALS AND METHODS

This retrospective study included 16 OTCA/f-TCA and 37 UF-iaa patients who underwent conventional MRI and DWI between August 2014 and September 2018. Three-dimensional TA was performed with T2-weighted MRI. The clinical, MRI-based and texture features were compared between OTCA/f-TCAs and UF-iaas. Multivariate logistic regression analysis was used for filtering the independent discriminative features and constructing the discriminating model. ROCs were generated to analyse MRI-based features, texture features and their combination for discriminating between the two diseases.

RESULTS

Six imaging-based features (ipsilateral ovary detection, arterial period enhancement, lesion components, peripheral cysts, "whorl signs", mean ADCs) and six texture features (Histogram-energy, Histogram-entropy, Histogram-kurtosis, GLCM-energy, GLCM-entropy, and Haralick correlation) were significantly different between OTCA/f-TCAs and UF-iaas (p < 0.05). Multivariate analysis of the MRI-based features revealed that arterial period enhancement (OR = 0.104), peripheral cysts (OR = 16.513), and whorl signs (OR = 0.029) were independent features for discriminating between OTCA/f-TCAs and UF-iaas (p < 0.05). Multivariate analysis of the texture features showed that Histogram-energy and GLCM-energy were independent features for discriminating between OTCA/f-TCAs and UF-iaas (p < 0.05). The area under the curve of imaging-based diagnosis was 0.85, and the combination of imaging-based diagnosis and TA improved the area under the curve to 0.87, with higher accuracy, specificity and sensitivity of 86%, 92%, and 84%, respectively (p < 0.05).

CONCLUSIONS

MRI-based features can be useful in differentiating OTCA/f-TCAs from UF-iaas. Furthermore, combining imaging-based diagnosis and TA can improve diagnostic performance.

Magnetic resonance imaging in categorization of ovarian epithelial cancer and survival analysis with focus on apparent diffusion coefficient value: correlation with Ki-67 expression and serum cancer antigen-125 level

Background

To determine whether magnetic resonance (MR) imaging features combined with apparent diffusion coefficient (ADC) values could be used as a tool for categorizing ovarian epithelial cancer (OEC) and predicting survival, as well as correlating with laboratory tests (serum cancer antigen 125, serum CA-125) and tumor proliferative index (Ki-67 expression).

Methods and materials

MRI examination was undertaken before invasive procedures. MRI features were interpreted and recorded on the picture archive communication system (PACS). ADC measurements were manually performed on post-process workstation. Clinical characteristics were individually retrieved and recorded through the hospital information system (HIS). Cox hazard model was used to estimate the effects of both clinical and MRI features on overall survival.

Results

Both clinical and MRI features differed significantly between Type I and Type II cancer groups (p < 0.05). The mean ADC value was inversely correlated with Ki-67 expression in Type I cancer (ρ = − 0.14, p < 0.05). A higher mean ADC value was more likely to suggest Type I ovarian cancer (Odds Ratio (OR) = 16.80, p < 0.01). Old age and an advanced International Federation of Gynecology and Obstetrics (FIGO) stage were significantly related to Type II ovarian cancer (OR = 0.22/0.02, p < 0.05). An advanced FIGO stage, solid components, and old age were significantly associated with poor survival (Hazard Ratio (HR) = 23.54/3.69/2.46, p < 0.05). Clear cell cancer type had a poorer survival than any other pathological subtypes of ovarian cancer (HR = 13.6, p < 0.01).

Conclusions

MR imaging features combined with ADC value are helpful in categorizing OEC. ADC values can reflect tumor proliferative ability. A solid mass may predict poor prognosis for OEC patients.

Electronic supplementary material

The online version of this article (10.1186/s13048-019-0534-0) contains supplementary material, which is available to authorized users.

Ovarian microcystic stromal tumor: Radiologic-pathologic correlation

Ovarian microcystic stromal tumor (MST) is characterized by microcysts, solid cellular regions with lobulated growth, and collagenous or fibrous stroma forming hyaline plaques. While several reports have evaluated the unique pathologic and immunohistochemical profile of these tumors, there has been limited description of the radiologic findings of ovarian microcystic stromal tumor in the literature. We present a case of a 66 year old female who presented for evaluation of a new cystic pelvic mass found to have ovarian microcystic stromal tumor. To our knowledge, this is one of the first reports to evaluate the radiologic features associated with this tumor. An enhanced understanding of the correlation between imaging appearance and specific histopathologic findings may aid in the early recognition of this rare neoplasm.

MR findings of primary ovarian granulosa cell tumor with focus on the differentiation with other ovarian sex cord-stromal tumors

BACKGROUND

To describe magnetic resonance imaging (MRI) features of ovarian granulosa cell tumors (OGCTs) and compare with other sex cord-stromal tumors (OSCs) in ovary.

METHODS

MR findings of 18 patients with surgically confirmed ovarian granulosa cell tumor were retrospectively reviewed by two radiologists with consensus reading. All MR examinations were prospectively performed within one month. Clinical and imaging characteristics of OGCTs were evaluated and compared with OSCs (control group).

RESULTS

In 18 patients, 20 ovarian granulosa cell tumors were detected on MRI. Sixteen tumors appeared as solid or mostly solid mass (16/20), while 4 tumors as cystic mass. Pathological pelvic fluid was detected in 1 OGCT (1/18) and 11 OSCs (11/34) (p = 0.031).On T2 weighted imaging (T2WI), most of OGCTs displayed hyperintense signal and mixed signal (19/20); on T1 weighted imaging (T1WI), 11 OGCTs (11/20) displayed similar signal as on T2WI imaging. The lesion signal between OGCT and OSC differed significantly on both T1WI (p = 0.017) and T2WI (p = 0.002). Tumoral bleeding was detected in 6 OGCTs on MRI. On diffusion weighted imaging (DWI) images, OGCTs mostly appeared as high signal (16/20). Average apparent diffusion coefficient (ADC) value derived from DWI images in the OGCT group (0.84 ± 0.26× 10^- 3 mm²/s was less than the control group (1.22 ± 0.47 × 10^- 3 mm²/s) with statistical difference (p = 0.002).

CONCLUSIONS

MRI could provide important information in OGCT diagnosis. ADC value might be useful in differentiating OGCT from OSC.

Computed tomography and magnetic resonance imaging features of ovarian fibrothecoma

The aim of the present study was to investigate the imaging characteristics of ovarian fibrothecoma. The cases of 25 female patients with pathologically confirmed ovarian fibrothecomas were retrospectively reviewed. Tumor location, size, density, signal intensity, cystic degeneration, calcification, enhancement pattern and ascites were assessed by computed tomography (CT) (n=20) and magnetic resonance imaging (MRI) (n=5). Clinical and histological features were also evaluated. The results revealed that 23 (92.0%) patients were postmenopausal, with a mean age ± standard deviation (SD) of 60.7±10.8 years old. All 25 tumors were unilateral and a thickened endometrium was observed in 7 (28.0%) patients. In total, 24 (96.0%) tumors appeared to have well-defined boundaries, with 1 (4%) tumor exhibiting an obscure boundary. Tumors had a mean size of 9.8±5.3 cm. Solid and predominantly solid masses were found in 16 cases (64.0%), and cystic and predominantly cystic masses were found in 9 patients (36.0%). Solid regions of masses exhibited hypodensity or isodensity in 24 patients (96.0%), with 1 patient (4.0%) exhibiting hyperdensity. The mean CT value (± SD) was 44.2±12.8 HU (range, 31-79HU) in unenhanced images. All masses exhibited isointensity or slight hypointensity on T1-weighted imaging, and tumor parenchyma also exhibited slight hypointensity or isointensity on T2-weighted imaging compared with the myometrium, with or without areas of patchy hyperintensity. Contrast-enhanced CT or MRI scans were performed on 19 patients, and the solid components (94.7%) exhibited mild to moderate enhancement in 18 patients and 1 patient (5.3%) exhibited intense enhancement. Tumor size was positively correlated with the tumor cystic degeneration (r=0.77, P<0.001) and ascites (r=0.41, P<0.001). Therefore, ovarian fibrothecoma typically presents as solid or predominant solid masses with clear boundaries; the parenchyma of the tumor exhibits isodensity on CT scans, slight hypointensity or isointensity on MRI and mild enhancement following contrast-medium injection. The thickened endometrium observed in postmenopausal woman may also be a valuable imaging feature.

Sex cord-stromal tumors of the ovary: a comprehensive review and update for radiologists

Ovarian sex cord-stromal tumors are infrequent and represent approximately 7% of all primary ovarian tumors. This histopathologic ovarian tumor group differs considerably from the more prevalent epithelial ovarian tumors. Although sex cord-stromal tumors present in a broad age group, the majority tend to present as a low-grade disease that usually follows a nonaggressive clinical course in younger patients. Furthermore, because the constituent cells of these tumors are engaged in ovarian steroid hormone production (e.g., androgens, estrogens, and corticoids), sex cord-stromal tumors are commonly associated with various hormone-mediated syndromes and exhibit a wide spectrum of clinical features ranging from hyperandrogenic virilizing states to hyperestrogenic manifestations. The World Health Organization sex cord-stromal tumor classification has recently been revised, and currently these tumors have been regrouped into the following clinicopathologic entities: pure stromal tumors, pure sex cord tumors, and mixed sex cord-stromal tumors. Moreover, some entities considered in the former classification (e.g., stromal luteoma, stromal tumor with minor sex cord elements, and gynandroblastoma) are no longer considered separate tumors in the current classification. Herein, we discuss and revise the ultrasonography, computed tomography, and magnetic resonance imaging characteristics of the different histopathologic types and clinicopathologic features of sex cord-stromal tumors to allow radiologists to narrow the differential diagnosis when facing ovarian tumors.

Ovarian thecoma-fibroma groups: clinical and sonographic features with pathological comparison

Background

Ovarian thecoma-fibroma groups (OTFG) are uncommon sex cord-stromal neoplasms. The objective of the study was to demonstrate clinical and sonographic features of OTFG and compare with surgical histopathology.

Methods

A total of 61 patients with surgically proven OTFG were enrolled in this retrospective study to demonstrate its clinical and sonographic features and to compare with pathological findings. Gray scale and color Doppler sonography were performed presurgically with either transabdominal or transvaginal approach to image pelvic structures and lesions. The clinical findings and sonographic appearances were compared with the types of the OTFG tumors based on the histopathological diagnosis.

Results

The mean patient age was 53.57 (range, 26–86) years. There were 63.93% (39/61) patients in postmenopausal and 63.93% (39/61) patients with no clinical symptoms. Ultrasound findings of OTFG revealed as solid tumors with a typical feature of well-demarcated hypoechoic masses in 70.49% (43/61), among which 74.41% (32/43) tumors were smaller than 5 cm in diameter. There were 17 mixed echogenic masses with calcification, hemorrhage, or cyst, among which 70.59% (12/17) lesions were larger than 5 cm in diameter. Acoustic attenuation of the tumor was presented in 44.26% (27/61) of the cases. Doppler flow signals within the tumors were found in 20 cases (32.79%), in which 80% (16/20) had minimal or moderate flow signals. Ascites was detected in 32.79% (20/61) of the cases, Megi’s syndrome was found in 1 case. Final pathology revealed 41 (67.21%) thecoma-fibromas, 15 (24.59%) fibromas, 4 (6.56%) thecomas and 1 (1.64%) fibrosarcoma. There were 58 patients underwent cancer antigen 125 (CA125) test, and 20.69% (12/58) showed an elevated level. The diameter of tumors was found to be significantly correlated with CA125 level (p < 0.01) and the amount of ascites fluid (p < 0.05).

Conclusions

The typical sonographic features of OTFG include adnexal hypoechoic masses with clear border and acoustic attenuation as well as minimal Doppler flow signals. All the aforementioned features could make ultrasound imaging as a assistent tool improve the preoperative diagnostic accuracy.

Magnetic resonance imaging features of ovarian fibroma, fibrothecoma, and thecoma

OBJECTIVE

To retrospectively evaluate the conventional and functional (diffusion- or perfusion-weighted) magnetic resonance (MR) imaging features of ovarian fibroma, fibrothecoma, and thecoma.

MATERIALS AND METHODS

Histologically proven ovarian fibromas (n = 19), fibrothecomas (n = 7), and thecomas (n = 2) were reviewed (26 patients). The morphologic and signal intensity (SI) characteristics on conventional MR imaging (n = 28, all cases) were analyzed. The b 1000 signal intensity on diffusion-weighted image (DWI) (n = 22) and the time-to-signal intensity curve on perfusion-weighted image (PWI) (n = 7) were also analyzed. The presence and shape of the ipsilateral ovarian tissue surrounding the lesions were evaluated on T2-weighted image.

RESULTS

Twenty-two cases (79%) were predominantly solid tumor. Majority of the detected lesions exhibited the characteristic homogeneous low SI on T1- (24/28, 86%) and T2- (19/28, 68%) weighted image. Conversely, a number of lesions exhibited high SI (9/28, 32%) on T2-weighted image. Most lesions presented with a detectable ipsilateral ovary on T2-weighted image (24/28, 86%). Tumors larger than 6 cm more likely showed atypical morphology (mixed solid and cystic, cystic), atypical SI (high on T1- and T2-weighted image), and large amount ascites. Larger tumor group (>6 cm) was more likely diagnosed as fibrothecoma or thecoma than fibroma by pathology. On DWI, 16 lesions showed low b 1000 signal intensity (16/22, 73%). On PWI, all lesions showed curve type 1 or 2 (7/7, 100%), which tends to characterize benign lesions. All (16/16, 100%) pre-menopausal women had a detectable ipsilateral ovary, and six (60%) out of 10 post-menopausal women had a detectable ipsilateral ovary (p < 0.05).

CONCLUSIONS

Combining conventional morphologic and signal intensity characteristics with the findings from DWI or PWI might help differentiate ovarian fibroma, fibrothecoma, and thecoma from ovarian malignancy, although further prospective larger scale study using DWI and PWI is needed.

The Value of Diffusion-Weighted Imaging in the Differential Diagnosis of Ovarian Lesions: A Meta-Analysis

OBJECTIVES

The ability of contrast-enhanced MRI to distinguish between malignant and benign ovarian masses is limited. The aim of this meta-analysis is to evaluate the diagnostic performance of diffusion-weighted imaging (DWI) in differentiating malignant from benign ovarian masses.

METHODS

A comprehensive literature search was performed in several authoritative databases to identify relevant articles. The weighted mean difference (WMD) and corresponding 95% confidence interval (95% CI) were calculated. We also used subgroup analysis to analyze study heterogeneity, and evaluated publication bias.

RESULTS

The meta-analysis is based on 21 studies, which reported the findings for 731 malignant and 918 benign ovarian masses. There was no significant difference in apparent diffusion coefficient (ADC) values for DWI between benign and malignant lesions (WMD = 0.22, 95% CI = -0.02-0.47, p = 0.08). Subgroup analysis by benign tumor type revealed higher ADC values (or a trend toward higher values) for cysts, cystadenomas and other benign tumors compared to malignant masses (cyst: WMD = 0.54, 95% CI = -0.05-1.12, p = 0.07; cystadenoma: WMD = 0.73, 95% CI = 0.38-1.07, p < 0.0001; other benign tumor: WMD = 0.16, 95% CI = -0.13-0.46, p = 0.28). On the other hand, lower ADC values (or a trend toward lower values) were observed for endometrioma and teratoma compared to malignant masses (endometrioma: WMD = -0.09, 95% CI = -0.47-0.29, p = 0.64; teratoma: WMD = -0.49, 95% CI = -0.85-0.12, p = 0.009). Subgroup analysis by mass property revealed higher ADC values in cystic tumor types than in solid types for both benign and malignant tumors. Significant study heterogeneity was observed. There was no notable publication bias.

CONCLUSIONS

Quantitative DWI is not a reliable diagnostic method for differentiation between benign and malignant ovarian masses. This knowledge is essential in avoiding misdiagnosis of ovarian masses.

Value of diffusion-weighted imaging combined with conventional magnetic resonance imaging in the diagnosis of thecomas/fibrothecomas and their differential diagnosis with malignant pelvic solid tumors

Background

Our study aims to determine the value of diffusion-weighted imaging (DWI) combined with conventional magnetic resonance imaging (MRI) in the diagnosis of thecomas/fibrothecomas and their differential diagnosis with malignant pelvic solid tumors.

Methods

In total, 36 thecomas/fibrothecomas and 40 malignant pelvic solid tumors were included in our study. All patients underwent 1.5 T conventional MRI and DWI examinations except one patient with a fibrothecoma in whom DWI examination was not performed. The clinical features and characteristics of conventional MRI and DWI of these two groups were analyzed. Apparent diffusion coefficient (ADC) values were measured and compared between groups. Univariate analysis, multivariate logistic regression analysis, and the receiver operating characteristic curve were used for statistical analysis.

Results

All the thecomas/fibrothecomas showed isointensity on T1 weighted imaging (T1WI) and 77.8 % (28/36) lesions showed hypo- to isointensity on T2 weighted imaging (T2WI). After administration of contrast medium, 94.4 % (34/36) tumors appeared as minor to mild enhancement. On DWI, they showed a diversity of low to very high signal intensity. All malignant pelvic masses manifested as hyperintensity on T2WI and 87.5 % (35/40) tumors showed very high signal (grade 3) on DWI. Higher area under the curve (AUC) and specificity could be achieved by using the lowest ADC value than the mean ADC value. Multivariate logistic regression analysis showed that shape, signal intensity on T2WI, capsule, and the lowest ADC value were the important indicators in discriminating thecomas/fibrothecomas from malignant pelvic solid tumors.

Conclusions

The combination of DWI and conventional MRI is of great value in the diagnosis of thecomas/fibrothecomas and their differential diagnosis with malignant pelvic solid tumors.

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.

Algorithmic approach to solid adnexal masses and their mimics: utilization of anatomic relationships and imaging features to facilitate diagnosis

Solid adnexal masses, while less common than their cystic counterparts, may present a challenge for radiologists given the wide range of histologic entities that occur in this region. Pelvic masses, especially when large, can seem overwhelming at first but application of an algorithmic approach allows for more confident assessment. This approach focuses first on the use of anatomic relationships and interactions of various pelvic structures to localize the mass' origin. For instance, the directionality of ureteral displacement can suggest if a mass is intra or extraperitoneal. Then, key discriminating imaging features, such as the presence of fat, hypervascularity, or low T2 signal on magnetic resonance imaging (MRI) can be applied to further narrow the list of diagnostic possibilities. Entities such as leiomyomas, nerve sheath tumors, congenital uterine anomalies, and vascular abnormalities (ovarian torsion or iliac vessel aneurysm) in particular are often accurately characterized with sonography and/or MRI. For solid adnexal masses in which a definitive diagnosis by imaging is not reached, information germane to clinicians regarding further management can still be provided, principally with regard to surgical vs. nonsurgical treatment.

MRI diagnosis of ovarian fibrothecomas: tumour appearances and oestrogenic effect features

OBJECTIVE

To study MRI diagnosis of ovarian fibrothecomas.

METHODS

MRI appearances of 27 ovarian fibrothecomas 26 female patients confirmed by surgical pathology were retrospectively reviewed and correlated with clinical and histological findings.

RESULTS

Most patients were post-menopausal females 73.1% (19/26) of cases. 38.5% (10/26) of patients showed an elevated serum carbohydrate antigen 125 (CA-125) level (>35 U ml(-1)). On MR T2 weighted imaging, 3 distinct features were revealed. (1) Homogeneous hypointense masses in 25.9% (7/27) cases. (2) Heterogeneous tumours with mostly isointense and few patchy hyperintense areas in 51.9% (14/27) cases. (3) Heterogeneous tumours with predominantly hyperintense and few isointense parts in 22.2% (6/27) cases. On T1 weighted imaging, all the fibrothecomas turned out to be homogeneous masses except six cystic degeneration cases. After contrast, 70.4% (19/27) tumours showed homogeneous mild enhancement in all phases. Beyond the tumours, endometrial abnormality and uterus enlargement were found in 38.5% (10/26) and 15.4% (4/26) patients, respectively. Ascites were seen in 53.8% (14/26) patients. There was a statistically significant difference among the 3 T2 weighted image features (F = 7.024; p = 0.003) in terms of the size of fibrothecomas. The cystic tumours also had the tendency to show the ascite condition (p = 0.002) as well as elevated serum CA-125 levels (p = 0.014). Vimentin was positively stained in 10 (76.9%) of 13 cases who underwent the immunohistochemical analysis.

CONCLUSION

MRI has the superiority to show the distinct appearances of tumours as well as their functional features according to oestrogenic effect.

ADVANCES IN KNOWLEDGE

This study describes the unique features of fibrothecomas on MRI on a relatively large series of patients with tumours and the indirect oestrogenic effect findings.