Prediction of Efficacy for Atezolizumab/Bevacizumab in Unresectable Hepatocellular Carcinoma with Hepatobiliary-Phase Gadolinium Ethoxybenzyl-Diethylenetriaminepentaacetic Acid MRI.

BACKGROUND: This study aimed to examine whether the coefficient of variation (CV) in the hepatobiliary-phase (HBP) of Gd-EOB-DTPA-MRI could be an independent predictive factor for tumor progression. METHODS: Patients who underwent Gd-EOB-DTPA-MRI before Atezolizumab/bevacizumab therapy at six affiliated institutions between 2018 and 2022 were included. CV for each patient was calculated as the mean value for up to five tumors larger than 10 mm, and CV of the whole tumor was calculated using LIFEx software. The tumor response was evaluated within 6-10 weeks. The primary endpoint was to investigate the predictive factors, including CV, related to tumor progression using logistic regression analysis. The secondary endpoints were tumor response rate and progression-free survival (PFS) based on CV. RESULTS: Of the 46 enrolled patients, 13 (28.3%) underwent early progressive disease. Multivariate analysis revealed that a high CV (≥0.22) was an independent predictive factor for tumor progression (p = 0.043). Patients with a high CV had significantly frequent PD than those with a low CV (43.5 vs. 13.0%, p = 0.047). Patients with a high CV tended to have shorter PFS than those with a low CV (3.5 vs. 6.7 months, p = 0.071). CONCLUSION: Quantitative analysis using CV in the HBP of Gd-EOB-DTPA-MRI may be useful for predicting tumor progression for atezolizumab/bevacizumab therapy.

Leydig cell tumor of the testis with characteristic contrast patterns of tumor and non-tumorous testicular parenchyma on MRI: a case report.

PURPOSE: Testicular Leydig cell tumor (LCT) is a rare subtype of testicular neoplasms that occurs in the interstitial tissue of testes, accounting for 1-3% of total testicular masses removed annually. We report a case of 70-year-old man diagnosed as testicular LCT. This report demonstrates a testicular LCT with intratumoral and non-tumorous testicular parenchymal enhancement in the affected testis, which should be considered characteristic findings of LCT. METHODS: Ultrasonography showed a hypoechoic mass. On magnetic resonance imaging, the tumor showed low signal intensity comparable to the surrounding testicular tissue on T1-weighted images (T1WI) and low signal intensity on T2-weighted images (T2WI). On gadolinium contrast-enhanced T1WI (CE-T1WI), the tumor showed a rapid and marked wash-in and subsequent prolonged washout. The spared, non-tumorous testicular parenchyma showed slow and progressive enhancement in the early phase, which was as strong as or stronger than that of the mass in the delayed phase. The patient underwent right orchiectomy. RESULTS: Pathologically, the tumor was diagnosed as a testicular Leydig cell tumor (LCT). Leydig cell proliferation was observed with well-developed microvessels, atrophy of the seminiferous tubules, and stromal edema in the non-tumorous testicular parenchyma. Leydig cells in the non-tumorous parenchyma were positive for estrogen receptors. CONCLUSION: Since the contrast findings in the non-tumorous testicular parenchymal region on CE-T1WI likely match the histopathological features of LCT, our case suggests that the presence of non-tumorous testicular parenchymal enhancement on imaging might indicate a diagnosis of LCT.

Evaluation of background parenchymal enhancement in breast contrast-enhanced ultrasound with Sonazoid®.

PURPOSE: The objective of this study was to retrospectively evaluate the association between background parenchymal enhancement (BPE) on contrast-enhanced ultrasound (CEUS) with Sonazoid® and patient characteristics. Additionally, background parenchymal tissues with the high-contrast effect were pathologically observed compared to those showing the low-contrast effect. METHODS: A total of 65 patients who underwent breast CEUS with Sonazoid® between January 2010 and November 2013 were enrolled. Regions of interest (ROIs) were put on the tumor and on the background parenchymal tissue. The dB values during the nonenhanced time and at peak contrast enhancement were measured based on the time intensity curve (TIC) drawn by the ROI. The differences in the dB values of pre- and post-enhanced time were obtained separately for ROIs on the tumor and ROIs on the parenchymal tissue. The patient characteristics studied were age, menstrual status, mammographic density, BPE on magnetic resonance imaging (MRI), and pathological diagnoses of breast tumors. RESULTS: There was a weak negative correlation between BPE on CEUS and age. As for the contrast effect of parenchymal tissue, there was a significant difference between the menstruating and menopausal groups. There was no significant difference among the levels of mammographic density, and among the degrees of contrast effect on MRI. BPE on CEUS was the same between those with a malignant tumor and those with a benign tumor in each menstrual status. The parenchymal tissue with the low-contrast effect showed pathological atrophy. CONCLUSION: The degree of BPE on CEUS appeared related to age, menstruating or menopausal, and atrophy of breast tissue. BPE on CEUS was the same between those with a malignant tumor and those with a benign tumor in each menstrual status.

MR findings of Lynch syndrome-related uterine endometrial carcinoma: a case report.

A 41-year-old woman presented with atypical genital bleeding. Magnetic resonance imaging demonstrated a polypoid mass from the lower uterine segment to cervical canal, approximately 32 mm in size. Additionally, a thickened sigmoid colon wall showing a markedly high signal intensity on diffusion-weighted imaging was observed. Barium enema and colonoscopy revealed a type I sigmoid colon cancer. Since this patient was relatively young and had multiple relatives with colon cancer, Lynch syndrome was suspected and proved by an immunohistochemical survey. Uterine endometrial carcinoma related to Lynch syndrome tends to occur in the lower uterine segment. Radiologists should be aware of this syndrome so that the correct diagnosis can be suggested in the imaging report.

Visualization of ovarian tumors using 3T MR imaging: diagnostic effectiveness and difficulties.

PURPOSE: We evaluated the diagnostic effectiveness of magnetic resonance (MR) imaging at 3 tesla to visualize ovarian tumors and problems associated with its use. MATERIALS AND METHODS: From the records of 423 consecutive women who underwent pelvic MR imaging using a 3T system from April 2009 to June 2010, we analyzed 50 continuous cases of ovarian tumors proved by histopathology. We evaluated visualization of these tumors for image quality and artifacts using 5-point scales. For qualitative assessment, we scored overall image quality (1, poor, to 5, excellent), degree of conviction regarding the diagnosis (1, undiagnosable, to 5, diagnosable with high certainty), and 4 representative artifacts (penetrating, chemical shift, motion, and susceptibility artifact) (1, severe, to 5, little degradation). We also retrospectively reviewed the diagnostic features of the ovarian tumors and preoperative diagnostic accuracy. For quantitative assessment, we determined tumor size and ADC value. RESULTS: Overall quality score was scored 4.9±0.5, and conviction regarding diagnosis was 4.9±0.3. Artifacts caused little degradation in most cases: penetrating, 4.8±0.5; chemical shift, 4.3±0.5; motion, 4.6±0.6; and susceptibility, 3.8±0.9. Preoperative diagnostic accuracy was 92% (sensitivity 94.7%, specificity 90.3%). Mean tumor diameter was 88.3±61 mm. The mean ADC value was 1.04±0.3 in malignant tumors and 1.15±0.5 (×10⁻6 mm²/s) in benign tumors. CONCLUSION: The quality of ovarian tumor images obtained with a 3T MR imaging system is adequate for diagnosis, with only slight degradation from penetrating or susceptibility artifacts.

[A case of ovarian cystadenofibroma with papillary projections showing very high signal intensity on T2-weighted images].

Cystadenofibromas are rare benign or borderline malignant neoplasms containing both epithelial and stromal components. We report a case of endometrioid cystadenofibroma in a patient with endometriosis. In this case, the solid component showed very high signal intensity on T2-weighted images and was enhanced after Gd-DTPA administration, reflecting marked stromal edema of fibrous tissue. Endometrial cysts with malignant transformation are reported to have an enhancing solid component and to show various intensities on T2-weighted imaging. However, a solid component showing very high signal intensity on T2-weighted images should also be considered stromal edema in benign or borderline cystadenofibromas.