Lack of response after initial chemoembolization for hepatocellular carcinoma: does it predict failure of subsequent treatment?

Purpose: To (a) evaluate the response of hepatocellular carcinoma (HCC) to chemoembolization after initial nonresponse, as determined with European Association for the Study of the Liver (EASL) criteria and modified Response Evaluation Criteria in Solid Tumors (mRECIST), and (b) compare posttreatment survival of initial nonresponders versus that of initial responders.

Materials And Methods: The institutional review board approved this retrospective study, which was compliant with HIPAA. A total of 116 consecutive patients (96 men, 20 women; mean age, 63 years) with unresectable HCC who underwent at least two chemoembolization procedures were included.

Implementation of screen-capture video recordings of resident conferences in an academic radiology department: pilot experience.

Rationale And Objectives: Didactic lectures are an integral component of resident education, but many are missed because of postcall or away rotation status. The authors describe their pilot experience implementing an audiovisual recording program for didactic lectures and report residents' and faculty members' perceptions of this experience.

Materials And Methods: From July to October 2008, resident conference didactic lectures were recorded on a voluntary faculty basis and posted to a secure Web site using affordable ($500) commercially available equipment.

Combination of radiofrequency ablation with antiangiogenic therapy for tumor ablation efficacy: study in mice.

Purpose: To prospectively determine whether modulation of renal cell carcinoma (RCC) tumor microvasculature by using the antiangiogenic drug sorafenib could increase the extent of radiofrequency (RF)-induced coagulation in an RCC animal tumor model.

Materials And Methods: All investigations received animal care and utilization committee approval. RCC (human 786-0) was implanted subcutaneously into 27 nude mice.

CT perfusion for determination of pharmacologically mediated blood flow changes in an animal tumor model.

Purpose: To prospectively compare single- and multisection computed tomographic (CT) perfusion for tumor blood flow determination in an animal model.

Materials And Methods: All animal protocols and experiments were approved by the institutional animal care and use committee before the study was initiated. R3230 mammary adenocarcinoma was implanted in 11 rats.

Radiofrequency ablation: variability in heat sensitivity in tumors and tissues.

Purpose: To characterize the thermal dosimetry (ie, heating profile) of radiofrequency ablation (RFA) in multiple ex vivo tissues and in vivo tumor models.

Materials And Methods: RFA was performed for 3-24 minutes in ex vivo bovine livers (n=20), porcine kidneys (n=20), and turkey muscles (n=20) and in vivo canine venereal sarcomas (n=8). RFA was performed by using 1 and 3-cm long tips internally cooled electrodes.

High-power generator for radiofrequency ablation: larger electrodes and pulsing algorithms in bovine ex vivo and porcine in vivo settings.

Purpose: To prospectively maximize the extent of tissue coagulation by using a high-power (1000-W, 4000-mA) radiofrequency (RF) generator to optimize pulsing algorithms.

Materials And Methods: The institutional animal care and use committee approved the use of the animal model in the in vivo portion of this study. RF ablations (n = 258) were performed in ex vivo bovine livers by using a 500-kHz high-power generator.

Improved tumor destruction with arsenic trioxide and radiofrequency ablation in three animal models.

Purpose: To assess the extent of tumor blood flow reduction that is achievable with arsenic trioxide (As2O3) and the effect of As2O3 on radiofrequency (RF)-induced coagulation.

Materials And Methods: All animal protocols and experiments were approved by an institutional animal care and use committee before the start of the study. Experiments were conducted in three tumor models: intrarenal VX2 sarcoma in 27 rabbits, RCC 786-0 human renal cell carcinoma in 24 nude mice, and R3230 mammary adenocarcinoma in 40 rats.

Chemical tumor ablation with use of a novel multiple-tine infusion system in a canine sarcoma model.

Purpose: To determine whether larger confluent zones of ablation can be achieved in chemical ablation with use of a multiple-tine infusion device compared with standard needle infusion in a solid tumor model.

Materials And Methods: Multiple canine venereal sarcomas (N=42) were implanted in nine mildly immunosuppressed dogs (treated with 10 mg/kg cyclosporin A twice daily). Tumors incubated for 8-12 weeks grew to a diameter of 5.

Microwave ablation: results with a 2.45-GHz applicator in ex vivo bovine and in vivo porcine liver.

Purpose: To characterize the relationship between applied power and treatment duration in their effect on extent of coagulation produced with a 2.45-GHz microwave applicator in both an ex vivo and a perfused in vivo liver model.

Materials And Methods: All experimentation was approved by the Institute of Animal Care and Use Committee.

Radiofrequency ablation: importance of background tissue electrical conductivity--an agar phantom and computer modeling study.

Purpose: To determine whether radiofrequency (RF)-induced heating can be correlated with background electrical conductivity in a controlled experimental phantom environment mimicking different background tissue electrical conductivities and to determine the potential electrical and physical basis for such a correlation by using computer modeling.

Materials And Methods: The effect of background tissue electrical conductivity on RF-induced heating was studied in a controlled system of 80 two-compartment agar phantoms (with inner wells of 0.3%, 1.

Radiofrequency tumor ablation: insight into improved efficacy using computer modeling.

Objective: To use computer modeling of the Bio-Heat equation to demonstrate factors influencing RF ablation tissue heating.

Conclusion: Computer modeling demonstrates the importance of energy deposition, tumor and background tissue electrical and thermal conductivity, and perfusion on RF ablation outcomes.

Hybrid radiofrequency and cryoablation device: preliminary results in an animal model.

Purpose: To determine whether the simultaneous application of combined bipolar radiofrequency (RF) ablation and cryoablation in a hybrid system produces larger ablation zones than RF or cryoablation alone.

Materials And Methods: Multiple 15-minute ablations were performed in ex vivo bovine liver (n = 167) with a hybrid applicator system with RF ablation alone (0.3-0.

Review of radiofrequency ablation for renal cell carcinoma.

This review will discuss how minimally invasive, image-guided radiofrequency (RF) tumor ablation [i.e., coagulating tumor using short-duration heating (<15 minutes) by directly applying temperatures >50 degrees C via needle electrodes] is being incorporated as a clinical tool for the treatment of renal cell carcinoma.

DNA synthesis and neuronal apoptosis caused by familial Alzheimer disease mutants of the amyloid precursor protein are mediated by the p21 activated kinase PAK3.

Apoptotic pathways and DNA synthesis are activated in neurons in the brains of individuals with Alzheimer disease (AD). However, the signaling mechanisms that mediate these events have not been defined. We show that expression of familial AD (FAD) mutants of the amyloid precursor protein (APP) in primary neurons in culture causes apoptosis and DNA synthesis.