Diagnostic Performance of Preoperative Imaging in Endometrial Cancer.

BACKGROUND: Endometrial cancer is one of the most common gynecological malignancies. Because the findings mentioned in radiogram interpretation reports issued by diagnostic radiologists influence treatment strategies, we aimed to evaluate the diagnostic accuracy of preoperative computed tomography (CT) and magnetic resonance imaging (MRI) interpretation results in clinically relevant settings. METHODS: The clinical records of patients diagnosed with endometrial cancer treated at Tohoku University Hospital from January 2012 to December 2021 were reviewed. The preoperative and pathologically estimated cancer stages were compared based on the results mentioned in the radiogram interpretation report. RESULTS: The preoperative and postoperative cancer stages were concordant in 70.0% of the patients. By contrast, the cancer stage was underdiagnosed and overdiagnosed in 21.7% and 8.2% of the patients, respectively. The sensitivities of MRI for deep myometrial invasion, cervical stromal invasion, vaginal invasion, and adnexal metastasis were 65.1%, 58.2%, 33.3%, and 18.4%, respectively. The sensitivity and specificity for pelvic lymph node metastasis using a combination of CT and MRI were 40.9% and 98.4%, respectively. Those for para-aortic lymph node metastases using CT were 37.0% and 99.5%, respectively. CONCLUSIONS: The low sensitivity observed in this study clarified the limitations of preoperative diagnostic performance in current clinical practice.

Intraductal oncocytic papillary neoplasm of the pancreas: clinical and radiological features compared to those of intraductal papillary mucinous neoplasm.

PURPOSE: This study aimed to characterize the clinical and imaging findings of intraductal oncocytic papillary neoplasm of the pancreas (IOPN-P) compared to those of intraductal papillary mucinous adenoma/carcinoma (IPMA/IPMC). METHODS: This multi-institutional retrospective study reviewed the clinical, imaging, and pathological findings of 21 patients with pathologically proven IOPN-P. Twenty-one computed tomography (CT) and magnetic resonance imaging, and seven 18F-fluorodeoxyglucose (FDG)-positron emission tomography were performed before surgery. The following findings were evaluated: preoperative blood test results, lesion size and location, pancreatic duct diameter, contrast-enhancement effect, bile duct and peripancreatic invasion, maximum standardized uptake (SUVmax) value, and pathological stromal invasion. RESULTS: Serum carcinoembryonic antigen (CEA) and cancer antigen 19-9 (CA19-9) levels were significantly higher in the IPMN/IPMC group than in the IOPN-P group. Except in one patient, IOPN-P showed multifocal cystic lesions with solid components or a tumor in the main pancreatic duct (MPD) with dilatation. IOPN-P had a higher frequency of solid parts and a lower frequency of downstream MPD dilatation than IPMA. IPMC showed smaller overall cyst size, more radiological peripancreatic invasion, and worse recurrence-free and overall survival than IOPN-P. The average SUVmax value of IOPN-P was 7.5. Pathologically, 17 of the 21 IOPN-Ps had a malignant component, and six showed stromal invasion. CONCLUSION: IOPN-P shows cystic-solid lesions similar to IPMC but has lower serum CEA and CA19-9 levels, larger overall cyst size, lower frequency of peripancreatic invasion, and more favorable prognosis than IPMC. Moreover, the high FDG uptake by IOPN-Ps may be a characteristic finding of this study.

A case of intestinal malrotation apparent after laparoscopically total proctocolectomy followed by ileal-pouch-anal anastomosis for ulcerative colitis.

Intestinal malrotation (IM) is an abnormality due to a failure of the normal midgut rotation and fixation. We report a case of 46-year-old man with ulcerative colitis whose IM was apparent after laparoscopically total proctocolectomy (TPC) followed by ileal-pouch-anal anastomosis (IPAA) and ileostomy. There was no abnormal anatomy except for mobile cecum/ascending colon during the initial operation. Intestinal obstruction occurred after ileostomy closure. The computed tomography scan showed the duodeno-jejunal transition was located in right abdomen, the superior mesenteric vein was located left of the superior mesenteric artery (SMA) and the obstruction point was the distal ileum near the pouch. We performed an ileo-ileo bypass across the ventral side of the SMA to relieve the intestinal obstruction. The patient would have incomplete IM preoperatively, which became apparent by TPC. In case of TPC for mobile colon, anatomy of small intestine should be checked before IPAA.

Prediction of placenta accreta spectrum using texture analysis on coronal and sagittal T2-weighted imaging.

PURPOSE: To separately perform visual and texture analyses of the axial, coronal, and sagittal planes of T2-weighted images and identify the optimal method for differentiating between the normal placenta and placenta accreta spectrum (PAS). METHODS: Eighty consecutive patients (normal group, n = 50; PAS group, n = 30) underwent preoperative MRI. A scoring system (0-2) was used to evaluate the degree of abnormality observed in visual analysis (bulging, abnormal vascularity, T2 dark band, placental heterogeneity). The axial, coronal, and sagittal planes were manually segmented separately to obtain texture features, and seven combinations were obtained: axial; coronal; sagittal; axial and coronal; axial and sagittal; coronal and sagittal; and axial, coronal, and sagittal. Feature selection using the least absolute shrinkage and selection operator method and model construction using a support vector machine algorithm with k-fold cross-validation were performed. AUC was used to evaluate diagnostic performance. RESULTS: The AUC of visual analysis was 0.75. The model 'coronal and sagittal' had the highest AUC (0.98) amongst the seven combinations. The fivefold cross-validation for the model 'coronal and sagittal' showed AUCs of 0.85 and 0.97 in training and validation sets, respectively. The AUC of the model 'coronal and sagittal' for all subjects was significantly higher than that of visual analysis (0.98 vs. 0.75; p < 0.0001). CONCLUSION: The model 'coronal and sagittal' can accurately differentiate between the normal placenta and PAS, with a significantly better diagnostic performance than visual analysis. Texture analysis is an optimal method for differentiating between the normal placenta and PAS.

MRI, CT and FDG-PET/CT findings of Wolffian tumor: four-case series.

ABSTARCT: PURPOSE: The purpose of this study is to describe the characteristic MRI, CT, and 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) findings of Wolffian tumor. METHODS: We reviewed preoperative images in four surgical cases of Wolffian tumor. MRI was available for review in all cases with additional diffusion-weighted images (DWI) in three, and contrast-enhanced images in two. CT was available in three. FDG-PET/CT was obtained in two. RESULTS: Two patients were asymptomatic, while the other two presented with acute abdomen. On MRI, all tumors were well-defined masses of increased signals on T2WI. Three tumors were solid, whereas the other was solid and cystic. The normal ipsilateral ovary was identified in two patients of reproductive ages, but not in two postmenopausal patients. Tumors in two patients presented with acute abdomen were complicated by hemorrhage. All three tumors evaluated on DWI showed high intensities. Contrast-enhanced images of MRI and CT showed homogeneous enhancement as the same degree as the myometrium. On CT, one tumor contained punctate calcifications. FDG-PET/CT showed moderate FDG accumulation. CONCLUSION: Wolffian tumors may be typically solid extraovarian tumors occasionally associated with cysts and calcifications. Although they are benign, they mimic malignancy due to high intensities on DWI and increased FDG accumulation.

Gaussian mixture model-based cluster analysis of apparent diffusion coefficient values: a novel approach to evaluate uterine endometrioid carcinoma grade.

OBJECTIVES: The purpose of our study was to perform Gaussian mixture model (GMM)-based cluster analysis of the apparent diffusion coefficient (ADC) data of patients with endometrioid carcinoma, and to evaluate the relationship between histological grade and the ratios of the different clusters in each patient. METHODS: This retrospective study enrolled 122 patients (training: n = 63; and validation: n = 59) imaged between May 2015 and February 2020. In the training cohort, manual segmentation was performed on the ADC maps to obtain the ADC data of each patient, and these ADC data were summated to obtain the "All-patient" ADC data. Cluster analysis (three clusters) was performed on this All-patient ADC data, and the ADC ranges of each cluster were defined as follows: cluster 1, 490-699 × 10-6 mm2/s; cluster 2, 700-932 × 10-6 mm2/s; and cluster 3, over 933 × 10-6 mm2/s. In the training and validation cohorts, the ADC data of each patient was classified into three clusters according to these ADC ranges. The cluster ratios of each patient were calculated and compared with histological grade. RESULTS: In the training cohort, a significant positive correlation was found between the cluster 1 ratio and histological grade (ρ = 0.34, p = 0.0059). The cluster 1 ratios of high-grade lesions (grade 3) were significantly higher than those of low-grade lesions (grades 1 and 2) (p = 0.0084). A similar significant positive correlation was found between the cluster 1 ratio and histological grade in the validation cohort (ρ = 0.44, p = 0.0006). CONCLUSIONS: The cluster 1 ratio containing voxels with low ADC was significantly correlated with the histological grade of endometrioid carcinoma. KEY POINTS: • We performed Gaussian mixture model (GMM)-based cluster analysis of the apparent diffusion coefficient (ADC) data of patients with endometrioid carcinoma. • The cluster 1 ratio, which included low ADC values, was significantly positive correlated with histological grade in the training and validation cohorts. • The GMM-based cluster analysis of voxel-based ADC data was effective for grading endometrioid carcinoma.

MR Imaging of Uterine Epithelioid Trophoblastic Tumor: A Case Report.

Epithelioid trophoblastic tumor (ETT) is a rare gestational trophoblastic neoplasm of chorionic-type intermediate trophoblasts, and it is most frequently located in the lower uterine segment and endocervix. Due to the epithelial-growth pattern with geographic necrosis exhibited by the neoplastic cells, ETT is commonly confused, both clinically and pathologically, with squamous cell carcinoma. Although there have been no previous reports of ETT focusing on computed tomography (CT) or magnetic resonance imaging (MRI) findings, we report a case of uterine ETT with special attention to the MRI findings referring to the pathological findings and MR images of previous reports. A 42-year-old Japanese woman (gravid 1, para 1) presented with uterus enlargement during screening, and complained of recent-onset lower abdominal pain. The MRI showed a solid tumor throughout the entire myometrium of the lower uterine segment, with the hemorrhagic cystic portion extending to the posterior subserosal space. Following hysterectomy, the final pathological diagnosis was ETT. An ETT is essentially a solid tumor composed of intermediate trophoblasts that exhibit an epithelial-like growth pattern and contain geographic necrosis with calcification. In our case, MRI revealed a non-specific-intensity solid tumor in the lower uterine segment with massive necrosis and hemorrhage extending to the subserosa. While it is difficult to distinguish between ETT and uterine carcinomas, recognition of certain tumor shapes and necrosis could enable more accurate diagnosis before treatment.