Yasuhisa Kurata

Diagnostic performance of MR imaging findings and quantitative values in the differentiation of seromucinous borderline tumour from endometriosis-related malignant ovarian tumour

AbstractObjectivesTo evaluate the diagnostic performance of quantitative values and MRI findings for differentiating seromucinous borderline tumours (SMBTs) from endometriosis-related malignant ovarian tumours (MT).MethodsThis retrospective study examined 19 lesions from SMBT and 84 lesions from MT. The following quantitative values were evaluated using receiver-operating characteristic analysis: overall and solid portion sizes, fluid signal intensity (SI), degree of contrast-enhancement, and mean and minimum apparent diffusion coefficient (ADC) values of the solid portion. Two radiologists independently evaluated four MRI findings characteristic of SMBT, fluid SI on the T1-weighted image and SI of the solid portion on diffusion-weighted image. The diagnostic values of these findings and interobserver agreement were assessed.ResultsFor diagnosing SMBT, the mean ADC value of the solid portion showed the greatest area under the curve (0.860) (cut-off value: 1.31 × 10-3 mm2/s, sensitivity: 1.00, specificity: 0.61). The T2-weighted image (T2WI) high SI solid portion was the most useful finding, with high specificity and interobserver agreement (sensitivity, 0.58; specificity, 0.95–0.96, kappa = 0.96), followed by T2WI low SI core (sensitivity, 0.48–0.63; specificity, 0.98, kappa = 0.68).ConclusionMean ADC values of the solid portion, T2WI high SI solid portion, and T2WI low SI core were useful for differentiating SMBT from MT.Key Points• SMBT is a newly categorised ovarian tumour often associated with endometriosis. • Differentiation of SMBT from endometriosis-related malignant ovarian tumour is clinically important. • Diagnostic performances of quantitative values and MRI findings were evaluated. • Mean ADC value of the solid portion was the most useful value. • “T2WI high SI solid portion” was the most useful MRI finding.

Feasibility of Computed Diffusion Weighted Imaging and Optimization of b-value in Cervical Cancer

Purpose: To evaluate the feasibility of computed diffusion weighted imaging (DWI) in cervical cancer and investigate the optimal b-value using computed DWI. Methods: The present retrospective study involved 85 patients with cervical cancer in the International Federation of Gynecology and Obstetrics (FIGO) stage IB, IIA or IIB. DWI was obtained with b-values of 0, 100, 500 and 1000 s/mm2. Computed DWI with b-values of 800, 1000, 1300, 1600 and 2000 s/mm2 (cDWI800, cDWI1000, cDWI1300, cDWI1600, cDWI2000) were generated from all measured DWI (mDWI) data. Qualitatively, computed DWI was evaluated in terms of tumor conspicuity, signal suppression of the fat in the imaged area and total image quality by two radiologists independently with reference to mDWI with b-value of 1000 s/mm2. The b-value at which the signal of the endocervical canal was suppressed was recorded. Quantitatively, the signal intensities of tumor, myometrium, endocervical canal, endometrium, and gluteal subcutaneous fat were measured and represented as contrast ratios (CR). Results: Regarding tumor conspicuity and total image quality, significantly higher scores were obtained at cDWI1300 and cDWI1600 compared to the others (post-hoc comparison, P < 0.001), except for the total image quality between cDWI1000 and cDWI1600 in one reader. Signal suppression of the fat was the worst at cDWI2000. The signal intensity of the endocervical canal was suppressed in 24/27 cases on cDWI1600 and in 26/27 cases on cDWI2000. The CRs of tumor to myometrium, cervix, and endometrium increased with higher b-values, while the CRs of tumor to fat decreased and were statistically significant (post-hoc comparison, P < 0.001). Conclusion: Computed DWI with the b-values of 1300 and 1600 would be suitable for the evaluation of cervical cancer due to good tumor conspicuity.

Uterine peristalsis and junctional zone: correlation with age and postmenopausal status:

Background Although age-related change of junctional zone (JZ) of the uterus has been known, there has been no previous systematic study of age-related changes of uterine peristalsis that is observed as the wave conduction of the thickest or darkest area within the JZ. Purpose To examine the age-related changes of uterine peristalsis in pre and postmenopausal women using cine magnetic resonance imaging (MRI), and to determine the correlation between peristalsis and JZ on T2-weighted (T2W) imaging. Material and Methods Cine MRI analysis was performed in 64 premenopausal volunteers and in 43 postmenopausal women. The peristaltic frequency, JZ detectability, and JZ thickness were evaluated and compared between the two groups. In the premenopausal group, the correlations between age and each item was examined. In the postmenopausal group, the number of years after menopause was used instead of age. The correlation between peristaltic frequency and JZ detectability or thickness was also analyzed. Results Peristaltic frequency and JZ detectability significantly differed between the two groups, while JZ thickness did not. Peristaltic frequency did not vary significantly with age before menopause and no peristalsis was observed after menopause. JZ detectability did not change significantly with age or number of years after menopause, while JZ thickness significantly increased with age before menopause, but did not vary after menopause. A significant moderate correlation was observed between JZ detectability and peristaltic frequency, but not between JZ thickness and peristaltic frequency. Conclusion Uterine peristalsis frequency did not change significantly according to age, but observed peristalsis on MRI significantly decreased after menopause.

Two cases of Wolffian tumor with novel magnetic resonance imaging findings reflecting characteristic pathology

A Wolffian tumor is a rare tumor arising from the remnants of the mesonephric duct. Herein, we report two cases. A 61‐year‐old woman presented with swollen left adnexa. On T2 weighted magnetic resonance imaging (MRI), a 4.4 cm solid pelvic mass showed slightly high signal intensity, with a low‐signal‐intensity rim. Microscopically, cuboidal cells with bland nuclei were arranged in a dense tubular form.

Longitudinal changes in magnetic resonance imaging of malignant and borderline tumors associated with ovarian endometriotic cyst comparing with endometriotic cysts without arising malignancy

PURPOSE To investigate magnetic resonance (MR) findings and to detect malignant transformation of ovarian endometriotic cysts by comparing longitudinal changes in patients with ovarian malignant/borderline tumors associated with ovarian endometriotic cysts (tumor group) with those of patients with endometriotic cysts (control group). METHODS Tumor group patients (n = 10) had ovarian malignant/borderline tumors with pathologically confirmed association with endometriosis and available prior MRI of endometriotic cysts. Control group patients (n = 40) had been diagnosed more than two times as having ovarian endometriotic cysts by MRI examination. The tumor and solid portion sizes were measured. Two radiologists independently evaluated signal intensity (SI) of the cystic portion on both T1-weighted and T2-weighted images (WI), presence of shading on T2WI, and T2 dark spot sign in both groups and evaluate longitudinal changes of those findings. RESULTS Pathological diagnoses of the tumor group were clear cell carcinoma (n = 6), endometrioid carcinoma (n = 1), serous carcinoma (n = 1), mucinous borderline tumor (n = 1), and endometrioid borderline tumor (n = 1). Tumor size had increased significantly in the tumor group (p = .004), but not in controls. Solid portions were identified in all cases only when neoplasms were suspected. Disappearance of shading during the follow-up period was observed more in tumor group (n = 2) than in the controls (n = 0). No significant difference was found between groups in the SI on T1 and T2WI, and T2 dark spot sign for the two MR examinations. CONCLUSIONS The MR findings suggesting malignant transformation were emergence of a solid portion and increase in cyst size. Disappearance of shading also facilitates the follow-up of endometriotic cysts.

Differentiation of Seromucinous Borderline Tumor from Serous Borderline Tumor on MR Imaging

Purpose: Seromucinous borderline tumor (SMBT) is a newly categorized ovarian tumor in the 2014 revised World Health Organization (WHO) classification. SMBT is similar to serous borderline tumor (SBT) on MRI reflecting their pathological findings. This study was conducted to demonstrate the usefulness of MRI findings and quantitative values for differentiating SMBT from SBT. Methods: This retrospective study examined 23 lesions (20 patients) from SMBT and 26 lesions (22 patients) from SBT. The following quantitative values were evaluated using receiver-operating characteristics analysis: overall and solid portion sizes, intracystic fluid signal intensity (SI) ratio compared with skeletal muscle on T1weighted image (T1WI) and T2weighted image (T2WI), contrast enhancement (CE) ratio, and mean and minimum apparent diffusion coefficient values of the solid portion. Two radiologists evaluated the prevalence of MRI finding characteristics of SMBT and SBT. The SI of the intracystic fluid on T1WI and T2WI and the association with endometriosis were evaluated visually. Results: The CE ratio was significantly higher in SBT (P = 0.007). It achieved the highest area under the curve (AUC) (0.739). The fluid SI ratio on T1WI was higher in SMBT (P = 0.036, AUC = 0.676). Exophytic growth of the solid portion was observed only in SBT (P = 0.011). Intracystic fluid SI of SMBT was higher on T1WI and lower on T2WI in visual evaluation (P = 0.008 and 0.007, respectively). Findings suggesting endometriosis were observed more frequently in SMBT patients (P = 0.019). Conclusion: Higher CE ratio of the solid portion and exophytic growth were findings suggesting SBT. Higher intracystic fluid SI on T1WI and lower SI on T2WI suggested SMBT. MRI findings suggesting endometriosis favored the diagnosis of SMBT.

Unenhanced region on magnetic resonance imaging represents tumor progression in uterine carcinosarcoma

Objective Carcinosarcoma of the uterine corpus has a poor prognosis. Although pathological necrosis is a prognostic factor of endometrial cancer, the clinicopathological influences of an unenhanced region observed on magnetic resonance imaging (MRI) are inconclusive. The aim of our study was to determine the clinicobiological impact of the presence of an unenhanced region on MRI, which can represent necrosis, in uterine carcinosarcoma. Methods The clinicopathological factors of 29 patients diagnosed with uterine carcinosarcoma were assessed retrospectively. The percentage of the tumor that was unenhanced on MRI was determined. The clinicopathological factors related to the unenhanced regions were evaluated. The prognostic significance was assessed using the Kaplan-Meier method and Cox regression model. Results Although the presence of pathological necrosis was not a poor prognostic factor (p=0.704), unenhanced regions on MRI correlated with poor prognosis when the unenhanced regions in the tumor accounted for more than 10% of the total tumor (p=0.019). The percentage of unenhanced regions was positively correlated with stage (p=0.028; r=0.4691) and related to tumor size (p=0.086; r=0.3749). The Cox regression analysis indicated that the presence of lymph node (LN) metastasis and more than 10% of the tumor being unenhanced on MRI were prognostic factors of overall survival in the univariate analyses (p=0.018 and p=0.047, respectively). Conclusion The unenhanced region on MRI, which represents pathological necrosis, reflects tumor progression, and semi-quantification of the region is useful to predict the prognosis in patients with uterine carcinosarcoma.

MRI findings of chronic abruption-oligohydramnios sequence (CAOS): report of three cases

Chronic abruption-oligohydramnios sequence (CAOS), characterized by chronic vaginal hemorrhage and oligohydramnios, is a rare clinical condition of pregnancy. Because CAOS is associated with preterm delivery and lung injury to the infant, it is a major clinical concern. This report describes three CAOS cases which presented characteristic MRI findings reflecting CAOS pathological mechanisms and pathological findings. First, in all cases, the placenta detached from the uterus at the peripheral portion of the placenta because of placental marginal hematoma. Because the cause of CAOS is presumed to be chronic peripheral separation of the placenta developing from bleeding from the peripheral vein of the placenta, the MRI finding corresponds to the CAOS pathophysiology. Second, the placental marginal hematoma spread extensively along the decidua. This MRI finding can explain the vaginal hemorrhage of CAOS patients. Finally, the amniotic fluid of all patients showed high signal intensity on T1-weighted images, suggesting that amniotic fluid contains blood-derived products. In CAOS patients, chronic venous bleeding engenders the release of blood-derived products into the amniotic cavity. The aspiration of these products might be a cause of lung injury to the fetus. We presented these MRI findings with radiologic–pathologic correlation.