Diagnostic performance of sonohysterography and MRI diffusion in benign endometrial lesion characterization

Diagnostic value of the apparent diffusion coefficient in differentiating malignant from benign endometrial lesions

Introduction

Magnetic resonance imaging (MRI) with its innovative techniques, such as diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC), increases the diagnostic accuracy in distinguishing between malignant and benign lesions of the endometrium. The aim of the study was MRI differentiation between malignant and benign endometrial lesions and correlation with histopathological findings with a special emphasis on quantitative analysis. An additional aim was to correlate the ADC values and histological tumor grades.

Methods

The prospective study included 119 female patients with or without vaginal bleeding and pathological values of endometrial thickness, who underwent MRI examinations. According to MRI reports the patients were divided into 45 suspicious malignant and 74 suspicious benign endometrial lesions. The radiological diagnosis was compared to the histopathological evaluation, which confirmed 37 malignant lesions while the rest were benign.

Results

The mean ADC value for malignant lesions was 0.761 ± 0.13×10^-3 mm²/s and for benign lesions was 1.318 ± 0.20×10^-3 mm²/s. The ADC values for malignant lesions were expectedly lower than those of benign lesions (p<0.001). The ADC cut-off value was 1.007×10^-3 mm²/s with a sensitivity of 100%, specificity of 92.7%, a positive predictive value of 60.3%, and a negative predictive value of 100%. In comparison with the histopathological findings, the sensitivity of MRI was 100%, specificity 90.2%, positive predictive value was 82.2%, and negative predictive value was 100%. Observing the histological grades 1, 2, and 3 of endometrial carcinoma, no statistically significant differences of mean ADC values were found. The mean ADC values for histological tumor grades 1,2 and 3 were 0.803 ± 0.13×10^-3 mm²/s, 0.754 ± 0.12×10^-3 mm²/s and 0.728 ± 0.13×10^-3 mm²/s, respectively.

Conclusion

DWI and ADC values represent clinically useful tools for the differentiation between malignant and benign endometrial lesions with high sensitivity and good specificity, but the results failed to demonstrate their usefulness in differentiating histological grades of endometrial cancer.

Multiparametric transvaginal ultrasound in the diagnosis of endometrial cancer in post-menopausal bleeding: diagnostic performance of a transvaginal algorithm and reproducibility amongst less experienced observers

OBJECTIVE

(a) To comparatively evaluate the performance of grayscale ultrasound features, power Doppler (PD) blood flow characteristics, and gel infusion sonography (GIS) in diagnosing endometrial cancer during real-time examination, (b) to compare the performance of real-time diagnosis of endometrial cancer by experienced observers with offline analysis by blinded observers using similar sonographic criteria during review of cine loop clips.

METHODS

152 females with post-menopausal bleeding (PMB) had ET ≥ 4 mm at first-line ultrasound were included. Two experienced radiologists evaluated endometrial patterns at real-time evaluation (grayscale ultrasound, PD, and GIS), then examinations were stored as video clips for later evaluation by two less-experienced radiologists. The reference standard was hysteroscopy (HY) and/or hysterectomy with the histopathological examination. The area under (AUC) the receiver operating characteristic (ROC) curve was calculated to assess the diagnostic performance for the prediction of endometrial cancer.

RESULTS

Among 152 females with ET ≥ 4 mm at first line TVUS, 88 (57.9%) patients had endometrial cancer on final pathologic analysis. Real-time ultrasound criteria (ET ≥ 5 mm with the presence of irregular branching endometrial blood vessels or multiple vessels crossing EM or areas with densely packed color-splash vessels with non-intact or interrupted EMJ at the grayscale ultrasound and/or GIS) correctly diagnosed 95% of endometrial cancers with 92% diagnostic efficiency.There is comparable accuracy of real-time evaluation (96%) and offline analysis (92%) after the exclusion of poor quality videos from the analysis. The diagnostic criteria showed good to an excellent agreement between real-time ultrasound and offline analysis.

CONCLUSION

When real-time ultrasound is performed with good technique, utilizing multiple parameters, it is possible to diagnose endometrial cancer with a high degree of accuracy and reproducibility.

ADVANCES IN KNOWLEDGE

when real-time ultrasound is performed with good technique, utilizing multiple parameters, it is possible to diagnose endometrial cancer with a high degree of accuracy and reproducibility.

Diagnostic efficacy of gel infusion sonography in post-menopausal bleeding

Background

Our purpose was to evaluate the diagnostic performance of two-dimensional transvaginal ultrasound (2D-TVUS) and gel infusion sonography (GIS) at offline analysis for endometrial characterization compared with real-time evaluation during scanning.

One hundred fifty women presented with PMB. At TVUS, endometrial thickness was ≥ 4 mm in 122 (81.3%) women and < 4 mm in 28 (18.72%). Among 122 women with endometrial thickness > 4 mm, GIS was successfully performed in 117 (95.9%). Examinations were stored as video clips for later evaluation (offline analysis) by two less experienced radiologists. Endometrial lesions were classified into four categories: no endometrial abnormality, hyperplasia, polyps, and cancer. Diagnostic efficiency of real-time and offline analysis for diagnosis of each category was calculated and compared, and inter-observer agreement for offline analysis was calculated.

Results

All patients underwent hysteroscopy and/or hysterectomy. Histopathological results confirmed no endometrial abnormality in (27.3%, 41/150), endometrial hyperplasia in (12.7%, 19/150), endometrial polyps in (17.3%, 26/150), and endometrial cancer in (42.7%, 64/150).

Overall diagnostic accuracy of real-time imaging was 89.7% (CI 84–91%)). The highest accuracy 92.7% (CI 88–98%) was seen in the diagnosis of cancer, and polyps 91.5% (CI 86–97%). The lowest accuracy 75% (CI 69–82%) was seen in hyperplasia.

Overall diagnostic accuracy of offline analysis was 81%, and it increased to 88% (CI 83–92%) after a restricted analysis of good quality clips. The highest accuracy 90.7% (CI 83–95%) was seen in the diagnosis of polyps, and cancer 90.4% (CI 83–96%). The lowest accuracy 71% (CI 69–75%) was seen in hyperplasia.

At offline analysis, the inter-observer agreement was substantial k = 0.77 (CI 71–84) in the evaluation of four endometrial categories after the exclusion of bad quality videos. It was excellent in exclusion of endometrial abnormalities k = 0.85 (0.78–0.90), substantial in the diagnosis of polyps k = 0.71 (0.69–0.88), cancer k = 0.61 (0.61–0.77), and moderate in the diagnosis of hyperplasia k = 0.41 (0.30–0.41).

Conclusion

Offline 2D analysis with a good image quality has comparable accuracy to a real-time evaluation during scanning in the diagnosis of endometrial lesions. It can increase the accuracy of sonography in ruling out endometrial abnormalities and diagnose non-hyperplastic endometrial pathologies. High NPV and substantial reproducibility can make it an efficient initial screening method in a post-menopausal bleeding.