Progressive Contrast Enhancement Research Articles

Epithelioid hemangioendothelioma of the liver: The role of hepatobiliary phase imaging for the preoperative diagnosis and qualification of patients for liver transplantation – preliminary experience

The aim of this study was to determine if the appearance of hepatic epithelioid hemangioendothelioma (HEHE) on state-of-the-art MRI including hepatocyte phase after administration of hepatobiliary contrast agent can facilitate preoperative diagnosis and identification of potential candidates for liver transplantation. The study group comprised 6 patients with pathologically confirmed HEHE. Analysis included signal characteristics of 55 tumor nodules (maximum of 10 lesions per patient) on T2-weighted images, dynamic contrast-enhanced, 5-minute delayed, and hepatobiliary phase images. The most common feature of HEHE, observed in 84% of lesions, was progressive contrast-enhancement, followed by subcapsular location (66%), confluent appearance (60%) and hyper- or isointensity on hepatobiliary phase images (53%). In 5 of 6 patients, capsular retraction was observed. The appearance of HEHE on hepatobiliary phase images was variable, but examined tumors often demonstrated hyper- or isointensity, most probably due to prolonged retention of contrast material. These features, along with typical morphology (subcapsular, confluent nodules, with progressive enhancement and capsular retraction), may contribute to correct diagnosis and recognition of potential candidates for liver transplantation.

Mixed hepatocellular cholangiocarcinoma and intrahepatic cholangiocarcinoma in patients undergoing transplantation for hepatocellular carcinoma

Mixed hepatocellular cholangiocarcinoma (HCC-CC) and intrahepatic cholangiocarcinoma (I-CC) are increasingly being reported in patients with cirrhosis. The aims of this study were (1) to evaluate the incidence, imaging features, and posttransplant outcomes for patients who underwent transplantation for hepatocellular carcinoma (HCC) and were found to have HCC-CC or I-CC in the explant and (2) to compare the outcomes of these patients with those of controls with HCC who were matched (1:3) by the tumor size and the number of nodules in the explant. In the explant specimens of 10 of 302 patients (3.3%) who underwent liver transplantation (LT) for HCC, mixed HCC-CC or I-CC was identified. There were 4 additional incidental cases of HCC-CC. After a median follow-up period of 32 months, 8 of the 14 patients (57%) suffered from tumor recurrence, and the median disease-free survival time was 8 months. The cumulative risk of tumor recurrence was 40% and 70% at 1 and 5 years, respectively, for these 14 patients. When the 4 incidental cases were excluded, the study group with HCC-CC or I-CC (n = 10) had a significantly lower incidence of well-differentiated tumors (11.1% versus 43.3%, P < 0.02) and a higher rate of recurrence (60% versus 16.7%, P = 0.008) in comparison with the control group of patients with HCC (n = 30). The 1- and 5-year cumulative risks of tumor recurrence were 42% and 65%, respectively, in the study group and 10% and 17%, respectively, in the control group (P < 0.002). The actuarial 1- and 5-year patient survival rates without recurrence were also significantly lower in the study group (79% and 32% in the study group and 90% and 62% in the control group, P < 0.03). Dynamic contrast-enhanced computed tomography or magnetic resonance imaging showed progressive contrast enhancement throughout the arterial and portal venous phases without washout in 8 of the 10 patients. In conclusion, HCC-CC and I-CC are associated with a poor prognosis and a high rate of tumor recurrence after LT, and both tumors exhibit radiographic features that are distinct from those observed with HCC.

Eosinophilic cystitis associated with eosinophilic enterocolitis: case reports and review of the literature

We report three cases of eosinophilic cystitis. Contrast-enhanced computed tomography (CT) revealed characteristic bladder wall thickening exceeding 10 mm, with preservation of the mucosal lining and intense, progressive contrast enhancement on sequential arterial and delayed scans. Eosinophilic cystitis might have been associated with eosinophilic infiltration in other organs, such as the gastrointestinal tracts and liver.

Differentiation of Recurrent Glioblastoma Multiforme from Radiation Necrosis after External Beam Radiation Therapy with Dynamic Susceptibility-weighted Contrast-enhanced Perfusion MR Imaging

To investigate whether cerebral blood volume (CBV), peak height (PH), and percentage of signal intensity recovery (PSR) measurements derived from the results of T2-weighted dynamic susceptibility-weighted contrast material-enhanced (DSC) magnetic resonance (MR) imaging performed after external beam radiation therapy (EBRT) can be used to distinguish recurrent glioblastoma multiforme (GBM) from radiation necrosis. Fifty-seven patients were enrolled in this HIPAA-compliant institutional review board-approved retrospective study after they received a diagnosis of GBM, underwent EBRT, and were examined with DSC MR imaging, which revealed progressive contrast enhancement within the radiation field. A definitive diagnosis was established at subsequent surgical resection or clinicoradiologic follow-up. Regions of interest were retrospectively drawn around the entire contrast-enhanced region. This created T2-weighted signal intensity-time curves that produced three cerebral hemodynamic MR imaging measurements: CBV, PH, and PSR. Welch t tests were used to compare measurements between groups. Mean, maximum, and minimum relative PH and relative CBV were significantly higher (P < .01) in patients with recurrent GBM than in patients with radiation necrosis. Mean, maximum, and minimum relative PSR values were significantly lower (P < .05) in patients with recurrent GBM than in patients with radiation necrosis. These findings suggest that DSC perfusion MR imaging may be used to differentiate recurrent GBM from EBRT-induced radiation necrosis.

Neuroradiographic changes following convection-enhanced delivery of the recombinant cytotoxin interleukin 13—PE38QQR for recurrent malignant glioma

Convection-enhanced delivery (CED) is a novel method for delivering therapeutic agents to infiltrative brain tumor cells. For agents administered by CED, changes on magnetic resonance (MR) imaging directly resulting from catheter placement, infusion, and the therapeutic compound may confound any interpretation of tumor progression. As part of an ongoing multiinstitutional Phase I study, 14 patients with recurrent malignant glioma underwent CED of interleukin (IL) 13-PE38QQR, a recombinant cytotoxin consisting of human IL-13 conjugated with a truncated Pseudomonas exotoxin. Serial neuroradiographic changes were assessed in this cohort of patients. Patients were treated in two groups: Group 1 patients received IL13-PE38QQR before and after tumor resection; Group 2 patients received infusion only after tumor resection. Preoperative and postinfusion MR images were obtained prospectively at specified regular intervals. Changes were noted along catheter tracks on postresection MR images obtained in all patients. A simple grading system was developed to describe these changes. When MR imaging changes appeared to be related to IL1 3-PE38QQR, patients were followed up without instituting new antitumor therapy. As CED of therapeutic agents becomes more common, clinicians and investigators must become aware of associated neuroimaging changes that should be incorporated into toxicity assessment. We have developed a simple grading system to facilitate communication about these changes among investigators. Biological imaging modalities that could possibly distinguish these changes from recurrent tumor should be evaluated. In this study the authors demonstrate the challenges in determining efficacy when surrogate end points such as time to tumor progression as defined by new or progressive contrast enhancement on MR imaging are used with this treatment modality.