Yukio Miki

Single institutional experience of the treatment of angiosarcoma of the face and scalp

OBJECTIVE Angiosarcoma is a rare malignant neoplasm with a poor prognosis. A retrospective study was performed to accumulate radiotherapy (RT) data. METHODS Data from 17 patients with angiosarcoma of the face and scalp (AFS) who were treated with definitive RT between January 1999 and July 2011 were retrospectively analysed. The total radiation dose was 70 Gy, and the fractional doses were 2.0-2.5 Gy. Combined with RT, chemotherapy using docetaxel alone, recombinant interleukin-2 immunotherapy alone and both of these was performed in 10, 4 and 2 patients, respectively. Three patients underwent limited surgery before RT. RESULTS The response rate was 82%, and the median overall survival (OS) rate was 26 months. Locoregional relapse alone, distant metastasis alone and both of these were confirmed in 4, 5 and 4 patients, respectively. Patients treated with docetaxel showed a better prognosis (p=0.0477), a distant metastasis-free rate (p=0.0063) and a better in-field control rate, although the last was not statistically significant (p=0.1645). CONCLUSION Definitive RT combined with docetaxel chemotherapy provided an effective approach for treating AFS. ADVANCES IN KNOWLEDGE Since patients treated with chemoradiotherpy using docetaxel showed better OS and distant metastasis-free rates than those who did not receive docetaxel, it was warranted to continue use of docetaxel. In chemoradiotherapy at a dose of 70 Gy using docetaxel, 2-year in-field control rate was 67%.

Internal Hernias in the Era of Multidetector CT: Correlation of Imaging and Surgical Findings

Clinical diagnosis of internal hernias is challenging because of their nonspecific signs and symptoms. Many types of internal hernias have been defined: paraduodenal, small bowel mesentery-related, greater omentum-related, lesser sac, transverse mesocolon-related, pericecal, sigmoid mesocolon-related, falciform ligament, pelvic internal, and Roux-en-Y anastomosis-related. An internal hernia is a surgical emergency that can develop into intestinal strangulation and ischemia. Accurate preoperative diagnosis is crucial for appropriate management. Multidetector computed tomography (CT), with its thin-section axial images, high-quality multiplanar reformations, and three-dimensional images, currently plays an essential role in preoperative diagnosis of internal hernias. The diagnostic approach to internal hernias at multidetector CT includes detecting an intestinal closed loop, identifying the hernia orifice, and analyzing abnormal displacement of surrounding structures and key vessels around the hernia orifice and hernia sac. At each step, multidetector CT can depict pathognomonic findings. A saclike appearance suggests an intestinal closed loop in several types of internal hernias. Convergence, engorgement, and twisting of mesenteric vessels in the hernia orifice can be seen clearly at multidetector CT, especially with use of multiplanar reformations. For definitive diagnosis of an internal hernia, analysis of displacement of anatomic landmarks around the hernia orifice is particularly important, and thin-section images provide the required information. Detailed knowledge of the anatomy, etiology, and imaging landmarks of the various hernia types is also necessary. Familiarity with the appearances of internal hernias at multidetector CT allows accurate and specific preoperative diagnosis. (©)RSNA, 2015.

Predictors of silent brain infarction on magnetic resonance imaging in patients with nonvalvular atrial fibrillation: A transesophageal echocardiographic study

BACKGROUND Silent brain infarction (SBI) is often found in patients with atrial fibrillation (AF) and may be related to cognitive decline. We investigated the predictors of SBI on brain magnetic resonance imaging (MRI) using transesophageal echocardiography (TEE) in patients with nonvalvular AF. METHODS The study population consisted of 103 neurologically asymptomatic patients with nonvalvular AF who underwent TEE before transcatheter AF ablation (76 men; mean age 63 ± 10 years). Left atrial (LA) abnormalities such as LA thrombus, spontaneous echo contrast, or abnormal LA appendage emptying velocity (<20 cm/s) and complex plaques in the aortic arch defined as large plaques ≥4 mm thickness, ulcerated plaques, or mobile plaques were evaluated by TEE. All patients were screened for SBI by brain MRI. RESULTS Of 103 patients, 31 (30%) showed SBI on brain MRI. Most lesions were multiple (61%) and small (<15 mm) in diameter (84%). Patients with SBI had a higher prevalence of LA abnormalities (45% vs 14%; P < .001) and complex arch plaques (45% vs 7%; P < .001) compared with those without SBI. In a multivariate logistic regression analysis including age and CHADS2 score ≥2, LA abnormalities (odds ratio 4.13; 95% CI 1.34-12.72; P = .014) and complex arch plaques (odds ratio 4.82; 95% CI 1.23-18.92; P = .024) were independent predictors of SBI. CONCLUSIONS Left atrial abnormalities and complex arch plaques detected by TEE were closely associated with the presence of SBI on brain MRI, suggesting that microembolization of small thrombi derived from the fibrillating LA or advanced aortic atherosclerotic lesions may be important causes of SBI in patients with nonvalvular AF.

Squamous-lined cyst of the pancreas: Radiological-pathological correlation.

Pancreatic cystic lesions are increasingly being detected incidentally because of the increased use of cross-sectional imaging. Squamous-lined cysts of the pancreas (lymphoepithelial cyst, epidermoid cyst, and dermoid cyst) are rare cystic lesions lined with squamous epithelium. Distinguishing squamous-lined cysts from other cystic lesions of the pancreas is important to avoid unnecessary surgery, because squamous-lined cysts of the pancreas have no malignant potential. The purpose of this review is to describe findings on computed tomography and magnetic resonance imaging and the histopathological characteristics of squamous-lined cysts, and to summarize the key points of differential diagnosis for pancreatic cystic lesions.

Diffusion‐weighted imaging thermometry in multiple sclerosis

To prospectively investigate brain temperature using MR diffusion‐weighted imaging thermometry in multiple sclerosis (MS) patients and age‐matched healthy controls, to examine comparisons of brain temperature between MS patients and healthy volunteers, and to examine correlations between brain temperature and disease duration and between brain temperature and Expanded Disability Status Scale (EDSS) in MS patients.

Post-embolisation susceptibility changes in giant meningiomas: multiparametric histogram analysis using non-contrast-enhanced susceptibility-weighted PRESTO, diffusion-weighted and perfusion-weighted imaging

PurposeTo investigate imaging characteristics of post-embolised meningioma and to determine if SW imaging can delineate tumour ischaemia.Materials and methodsSixteen patients were studied before and after preoperative embolisation therapy (8 histopathologically determined with ischaemia, 8 with non-ischaemia). In each patient, a slice-wise ROI for the entire tumour was established, and histogram variables (mean, SD, minimum, maximum, histogram width, mode, and peak height) of SW, ADC, CBV, CBF, MTT, and TTP maps were compared between ischaemic and non-ischaemic groups. Changes in SW histogram were correlated with histopathological characteristics.ResultsSignal intensity on the SW map tended to decrease in the ischaemic group and partially increased in the non-ischaemic group. A similar trend was observed on the ADC map. The PW histogram showed an MTT increase in ischaemic group; however, CBV did not show significant changes between ischaemic and non-ischaemic groups. Microhaemorrhage was slightly correlated with Δpeak height in the SW histogram.ConclusionPost-embolisation changes of intrinsic T2*-weighted MR contrasts on SW map are most likely associated with alterations in deoxyhaemoglobin levels and arterial blood flow.Key Points•Endovascular embolisation is now accepted as an adjuvant therapy for intracranial meningioma.•Magnetic resonance imaging is used to assess the effects of embolisation.•Unenhanced susceptibility-weighted MRI can delineate ischaemic and non-ischaemic areas.•Signal changes at SW imaging are associated with diffusion and perfusion abnormalities.•Three-dimensional high-resolution SW imaging offers a new imaging biomarker in assessing ischaemia.

Efficacy and safety of intra-arterial steroid infusions in patients with steroid-resistant gastrointestinal acute graft-versus-host disease

There is no established second-line treatment for steroid-resistant acute graft-versus-host disease (GVHD). We prospectively assessed the safety and efficacy of intra-arterial steroid infusions (IASIs) for steroid-resistant acute gastrointestinal (GI) GVHD and compared the outcomes with those of historical controls at our institution. Nineteen consecutive, allogeneic hematopoietic stem cell transplantation subjects aged 31-67 years (median 52) were enrolled between October, 2008, and November, 2012. Acute GVHD was confirmed by biopsy in all cases. The enrolled patients were treated with infusions of methylprednisolone into the mesenteric arteries and/or gastroduodenal and left gastric arteries. Fourteen consecutive patients who developed steroid-resistant acute GI GVHD between 2001 and 2008 were used as controls. For the primary endpoint at day 28, the overall and complete responses in the IASI group trended higher (79% vs. 42%, p = 0.066) and were significantly higher (63% vs. 21%, p = 0.033) than those in the control group. Although not statistically significant, owing to the small population, the crude day-180-nonrelapse mortality rate was about 20% lower and the day-180-overall-survival rate tended to be higher than the control (11% vs. 29%, p = 0.222; 79% vs. 50%, p = 0.109, respectively). There were no serious IASI-related complications. Our results suggest that IASI can safely provide excellent efficacy for refractory acute GI GVHD without increasing infection-related complications and may improve prognosis.

Combination Radiofrequency Ablation and Local Injection of the Immunostimulant Bacillus Calmette–Guérin Induces Antitumor Immunity in the Lung and at a Distant VX2 Tumor in a Rabbit Model

PURPOSE To evaluate whether the combination of radiofrequency (RF) ablation and local injection of the immunostimulant Mycobacterium bovis bacillus Calmette-Guérin (BCG) induces systemic antitumor immunity. MATERIALS AND METHODS Japanese White rabbits with lung and auricle VX2 tumors were randomized into three groups: control (n = 8; no treatment), RF ablation only (n = 8; RF ablation to the lung tumor), and RF ablation with local BCG injection into the lung tumor (n = 8). Treatments were performed 1 week after tumor implantation. Survival was evaluated with Kaplan-Meier method and log-rank test. Weekly mean volume and specific growth rate (SGR) of auricle tumors were calculated, and comparisons were made by Mann-Whitney test. RESULTS Median survival of control, RF-only, and RF/BCG groups were 23, 41.5, and 103.5 days, respectively. Survival was significantly prolonged in the RF-only and RF/BCG groups compared with the control group (P = .034 and P =.003, respectively), but no significant difference was found between the RF-only and RF/BCG groups (P = .279). Only in the RF/BCG group was mean auricle tumor volume decreased 5 weeks after implantation. No significant difference in SGR was found between the control and RF-only groups (P = .959), but SGR in the RF/BCG group was significantly lower than in the control group (P = .005). CONCLUSIONS The combination of RF ablation and local injection of BCG resulted in distant tumor suppression compared with the control group, whereas RF ablation alone did not produce this effect. Therefore, the combination of RF ablation and local injection of BCG may induce systemic antitumor immunity.

Imaging findings of primary hepatic carcinoid tumor with an emphasis on MR imaging: case study

Carcinoid tumors are slow-growing tumors originating in the neuroendocrine cells, and occur most frequently within the gastrointestinal tract. Although the liver is the most common site for metastatic carcinoid tumors, primary hepatic carcinoid tumors are exceedingly rare and reports of the imaging findings have been very scarce. We herein report imaging findings with an emphasis on magnetic resonance imaging in two cases of primary hepatic carcinoid tumors. In both cases, the tumors showed cystic areas with hemorrhagic components and early enhanced solid areas.

90°-Flip-angle three-dimensional double-echo steady-state (3D-DESS) magnetic resonance imaging of the knee: Isovoxel cartilage imaging at 3 T

PURPOSE The purpose of this study was to investigate whether 3D-double echo steady state (3D-DESS) with improved contrast by setting the FA (Flip angle) at 90° is useful in 3D isotropic cartilage imaging of the knee at 3T. MATERIALS AND METHODS Imaging was performed in 10 healthy volunteers using 3 methods: with 3D-DESS using FA of 25° and 90°, and with true fast imaging with steady-state precession (True-FISP). The signal-to-noise ratio (SNR) of the synovial fluid and cartilage, and contrast-to-noise ratio (CNR) were measured, and mean values were compared. Visual assessment of artifacts was performed with the cartilage divided into 6 regions. RESULTS There were no significant differences in synovial fluid SNR in the comparison between FA-90° 3D-DESS and True-FISP (P=0.364). A significantly higher cartilage SNR was observed with FA-90° 3D-DESS than with True-FISP (P=0.031). There were no significant differences in synovial fluid-cartilage CNR between FA-90° 3D-DESS and True-FISP (P=0.892). In the evaluation of artifacts, FA-90° 3D-DESS imaging showed a significantly higher score than True-FISP imaging in the patella and trochlea cartilage (P<0.001, P<0.002). CONCLUSIONS FA-90° 3D-DESS is useful in 3D isotropic cartilage imaging of the knee at 3T.