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.

Bing Yin,Jian Chen,Yanfen Cui,Ming Ding,Ping Zhang,Wenhua Li,Xiangru Wu,Caiting Chu

doi:10.1186/s12957-015-0760-x

Abstract

BackgroundOur 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.MethodsIn 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.ResultsAll 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.ConclusionsThe 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.

Highlights

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
Most of the thecomas/ fibrothecomas were incidentally identified by health examinations, while the primary complaints included postmenopausal vaginal bleeding and abdominal pain
In the malignant pelvic solid masses group, all patients showed isointensity on T1 weighted imaging (T1WI) and hyperintensity on T2 weighted imaging (T2WI). All these results indicate that isointensity on T1WI and hypo- to isointensity on T2WI is the characteristic manifestation of thecomas/fibrothecomas and hyperintensity on T2WI was a significant indicator of pelvic malignant solid tumors (P = 0.006, OR = 117.274)

Summary

Introduction

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. Ovarian thecomas are rare mesothelial tumors with a sex-cord stromal origin, which account for 0.5–1 % of primary ovarian tumors and are the most common solid benign tumors of the ovary [1, 2]. Thecomas/fibrothecomas are mostly benign tumors and are rarely malignant [3, 4]. They are often asymptomatic and are usually identified incidentally [5]. Patients commonly complain of abdominal pain, abdominal distention, or abdominal masses They mostly affect menopausal and postmenopausal women but can occur in young patients with an average age of onset between 55 and 60 years [6]. They may present with ascites and pleural effusions, known as Meigs syndrome [7, 8]

Methods

Results

Discussion

Conclusion