Soft Reconstruction Kernels Improve HCC Imaging on a Photon-Counting Detector CT

RATIONALE AND OBJECTIVES

Hepatocellular carcinoma (HCC) is the only tumor entity that allows non-invasive diagnosis based on imaging without further histological proof. Therefore, excellent image quality is of utmost importance for HCC diagnosis. Novel photon-counting detector (PCD) CT improves image quality via noise reduction and higher spatial resolution, inherently providing spectral information. The aim of this study was to investigate these improvements for HCC imaging with triple-phase liver PCD-CT in a phantom and patient population study focusing on identification of the optimal reconstruction kernel.

MATERIALS AND METHODS

Phantom experiments were performed to analyze objective quality characteristics of the regular body and quantitative reconstruction kernels, each with four sharpness levels (36-40-44-48). For 24 patients with viable HCC lesions on PCD-CT, virtual monoenergetic images at 50 keV were reconstructed using these kernels. Quantitative image analysis included contrast-to-noise ratio (CNR) and edge sharpness. Three raters performed qualitative analyses evaluating noise, contrast, lesion conspicuity, and overall image quality.

RESULTS

In all contrast phases, the CNR was highest using the kernels with a sharpness level of 36 (all p < 0.05), with no significant influence on lesion sharpness. Softer reconstruction kernels were also rated better regarding noise and image quality (all p < 0.05). No significant differences were found in image contrast and lesion conspicuity. Comparing body and quantitative kernels with equal sharpness levels, there was no difference in image quality criteria, neither regarding in vitro nor in vivo analysis.

CONCLUSION

Soft reconstruction kernels yield the best overall quality for the evaluation of HCC in PCD-CT. As the image quality of quantitative kernels with potential for spectral post-processing is not restricted compared to regular body kernels, they should be preferred.

Vaccinia-based oncolytic immunotherapy Pexastimogene Devacirepvec in patients with advanced hepatocellular carcinoma after sorafenib failure: a randomized multicenter Phase IIb trial (TRAVERSE)

Pexastimogene devacirepvec (Pexa-Vec) is a vaccinia virus-based oncolytic immunotherapy designed to preferentially replicate in and destroy tumor cells while stimulating anti-tumor immunity by expressing GM-CSF. An earlier randomized Phase IIa trial in predominantly sorafenib-naïve hepatocellular carcinoma (HCC) demonstrated an overall survival (OS) benefit. This randomized, open-label Phase IIb trial investigated whether Pexa-Vec plus Best Supportive Care (BSC) improved OS over BSC alone in HCC patients who failed sorafenib therapy (TRAVERSE).

129 patients were randomly assigned 2:1 to Pexa-Vec plus BSC vs. BSC alone. Pexa-Vec was given as a single intravenous (IV) infusion followed by up to 5 IT injections. The primary endpoint was OS. Secondary endpoints included overall response rate (RR), time to progression (TTP) and safety.

A high drop-out rate in the control arm (63%) confounded assessment of response-based endpoints. Median OS (ITT) for Pexa-Vec plus BSC vs. BSC alone was 4.2 and 4.4 months, respectively (HR, 1.19, 95% CI: 0.78–1.80; p = .428). There was no difference between the two treatment arms in RR or TTP. Pexa-Vec was generally well-tolerated. The most frequent Grade 3 included pyrexia (8%) and hypotension (8%). Induction of immune responses to vaccinia antigens and HCC associated antigens were observed.

Despite a tolerable safety profile and induction of T cell responses, Pexa-Vec did not improve OS as second-line therapy after sorafenib failure. The true potential of oncolytic viruses may lie in the treatment of patients with earlier disease stages which should be addressed in future studies.

ClinicalTrials.gov: NCT01387555

[Cost-effective medical therapy of hepatitis C employing novel compensation models - pay for cure]

Direct acting antivirals (DAAs) have increased cure rates for chronic hepatitis C infection up to nearly 100 %. At the same time treatment costs have risen significantly. Treating all HCV infected patients in Germany with DAAs would generate medication costs ranging between 19 and 37 billion EUR depending on the drug regimen used. Expenses in patients who fail to respond to treatment would amount to approximately 0.9 to 2.15 billion EUR. In difficult to treat patient populations that are characterized by prior failure to treatment or advanced liver disease, lost drug expenses are particularly high due to lower cure rates and longer treatment duration. Outcome-based reimbursement schemes are used to improve the quality of care and to reduce costs in the health care system. In Germany, disease management programs have been implemented for defined chronic diseases. However, drug reimbursement is still based on packages sold (pay for pill). In this context, it would be appealing to link reimbursement and treatment success (pay for cure) in order to reward successful treatment, limit lost drug spending and develop a shared risk environment that would involve all concerned parties. Under the assumption that 20,000 patients with HCV are treated each year in Germany and that cure rates are 95.4 %, the saved treatment costs would amount up to 45 and 107 million EUR per year. By this approach, economic incentives to withhold therapy from difficult to treat patients could be avoided.

Targeting the actin cytoskeleton: selective antitumor action via trapping PKCɛ

Targeting the actin cytoskeleton (CSK) of cancer cells offers a valuable strategy in cancer therapy. There are a number of natural compounds that interfere with the actin CSK, but the mode of their cytotoxic action and, moreover, their tumor-specific mechanisms are quite elusive. We used the myxobacterial compound Chondramide as a tool to first elucidate the mechanisms of cytotoxicity of actin targeting in breast cancer cells (MCF7, MDA-MB-231). Chondramide inhibits cellular actin filament dynamics shown by a fluorescence-based analysis (fluorescence recovery after photobleaching (FRAP)) and leads to apoptosis characterized by phosphatidylserine exposure, release of cytochrome C from mitochondria and finally activation of caspases. Chondramide enhances the occurrence of mitochondrial permeability transition (MPT) by affecting known MPT modulators: Hexokinase II bound to the voltage-dependent anion channel (VDAC) translocated from the outer mitochondrial membrane to the cytosol and the proapoptotic protein Bad were recruited to the mitochondria. Importantly, protein kinase C-ɛ (PKCɛ), a prosurvival kinase possessing an actin-binding site and known to regulate the hexokinase/VDAC interaction as well as Bad phosphorylation was identified as the link between actin CSK and apoptosis induction. PKCɛ, which was found overexpressed in breast cancer cells, accumulated in actin bundles induced by Chondramide and lost its activity. Our second goal was to characterize the potential tumor-specific action of actin-binding agents. As the nontumor breast epithelial cell line MCF-10A in fact shows resistance to Chondramide-induced apoptosis and notably express low level of PKCɛ, we suggest that trapping PKCɛ via Chondramide-induced actin hyperpolymerization displays tumor cell specificity. Our work provides a link between targeting the ubiquitously occurring actin CSK and selective inhibition of pro-tumorigenic PKCɛ, thus setting the stage for actin-stabilizing agents as innovative cancer drugs. This is moreover supported by the in vivo efficacy of Chondramide triggered by abrogation of PKCɛ signaling shown in a xenograft breast cancer model.

Abstract P4-14-04: AVANTI: A non-interventional study examining the combination of bevacizumab with paclitaxel or capecitabine in metastatic breast cancer

Background: We initiated a large, multicentre, non-interventional study (NIS) to determine the safety and efficacy of treatment, as well as the selection criteria that influence choice of therapy (bevacizumab plus paclitaxel or capecitabine), for patients with metastatic breast cancer (MBC) treated in the context of routine oncology practice in Germany. The study also aimed to gather information on patient-reported quality of life and treatment satisfaction. Here we present an interim analysis of the safety and efficacy data.

Methods: Pre- or postmenopausal female patients aged ≥18 years with previously untreated locally advanced, recurrent, or MBC were enrolled if they were considered eligible for treatment with a combination of bevacizumab and either paclitaxel or capecitabine. Endocrine pretreatment was allowed. Patients with contraindications to bevacizumab were excluded. Kaplan-Meier estimates and Cox-regression were used to model survival data.

Results: Since October 2009, 1,807 patients have been recruited; this analysis includes data for 1,464 patients with a median age of 60.4 years (range: 23.6–86.4). Most patients had a performance status of 1 (43.1%) and HER2-negative (83.5%), hormone receptor-positive (70.2%) disease. The most common sites of metastasis were bone (52.3%), liver (39.3%) and lungs (33.4%); 736 patients (50.3%) had at least two documented metastatic sites. Bevacizumab plus paclitaxel (68.5% of patients) and bevacizumab plus capecitabine (12.0%) were the most frequently prescribed therapies. Other bevacizumab-containing combination regimens were prescribed to the remaining 19.5% of patients. The treatment decision factors cited most often were efficacy of therapy (62.4%), therapy guidelines (49.7%), tolerability of therapy (40.6%) and HER2 status (38.1%). The overall response rate (complete response [CR] + partial response [PR]) was 48.5% with 5.9% of patients achieving a CR. The disease control rate (CR + PR + stable disease) was 72.7%. At the time of data cut-off, 414 patients (28.3%) had experienced a progression-free survival (PFS) event. Median PFS was 9.5 months (95% CI: 8.8–10.1). Adverse events (AEs) and serious AEs were reported in 457 (31.2%) and 109 patients (7.4%), respectively. The most frequently reported AEs were hypertension (6.1% of patients), fatigue (5.5%), sensory neuropathy (4.6%), leukopenia (4.0%), nausea (4.2%) and diarrhoea (3.6%). Treatment was discontinued due to AEs in 72 patients (4.9%).

Conclusions: Interim results of this large NIS demonstrate that bevacizumab plus either paclitaxel or capecitabine combination therapy is well tolerated and active in patients with MBC representative of those treated in routine oncology practice. Follow-up is ongoing and final results of this interim analysis, as well as subgroup analyses, will be reported at the meeting.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-14-04.

P1-14-04: Prolonged (≥1 Year) Exposure to First-Line Bevacizumab Combined with Paclitaxel in Patients with HER2−Negative Metastatic Breast Cancer Treated in a Routine Oncology Practice Study

Background: First-line bevacizumab (BEV) combined with weekly paclitaxel (PAC) significantly improves progression-free survival (PFS) and response rate (RR) vs PAC alone in HER2−negative metastatic breast cancer (mBC), as shown in E2100. The benefit of BEV combined with other chemotherapy (CT) agents was demonstrated in AVADO and RIBBON-1. BEV was continued for ≥1 year in 21% of patients in the global ATHENA safety study and in 42% of patients in the JO19901 single-arm Japanese study of BEV-PAC. We analyzed data from the subgroup of patients treated for ≥1 year in a German routine oncology practice study to provide insight into the safety and efficacy of prolonged first-line BEV-PAC.

Methods: Patients who had received no prior CT for their mBC received BEV-PAC per the European label. Efficacy and safety were documented for up to 1 year (or until progression, death, or BEV discontinuation if earlier) with additional long-term follow-up. Data from patients treated with BEV for ≥1 year were extracted for this analysis.

Results: By Jan 2011, data were available for 818 patients, of whom 157 (19%) had already received BEV for ≥1 year. Baseline characteristics of this subset relative to the overall population are summarized in the table.

Abstract P2-16-12: First-Line Bevacizumab Combined with Paclitaxel in Triple-Negative Locally Recurrent/Metastatic Breast Cancer: Subpopulation Analysis of 115 Patients Treated in Routine Oncology Practice in Germany

Background: Both progression-free survival (PFS) and response rate (RR) are significantly improved when bevacizumab (Bev) is combined with first-line chemotherapy for locally recurrent/metastatic breast cancer (LR/mBC), as demonstrated in three randomized, phase III trials (E2100, AVADO, RIBBON-1). The benefit derived from Bev appears to be similar in triple-negative (TN) and non-TN LR/mBC according to subanalyses of the randomized trials. We conducted a subpopulation analysis of TN patients treated with first-line Bev-paclitaxel (Pac) in a large German observational study in the context of routine oncology practice. Methods: Patients with HER2-negative LR/mBC received first-line Bev-Pac according to the European label at the time of study design. Safety and efficacy data were collected for up to 1 year (or until progression, death, or Bev discontinuation if earlier). The endpoints were safety and efficacy (PFS and RR). We conducted an exploratory analysis of the subset of patients with TN disease.

Results: Of the 567 patients for whom data are currently available, 115 (20%) had TN disease. Baseline characteristics and efficacy are summarized below. Overall survival data are immature and follow-up is continuing.

Conclusions: In this ongoing study, first-line Bev-Pac demonstrated a 51% RR and median PFS of 7.7 months in patients with TN LR/mBC. These data are consistent with findings from retrospective analyses of randomized phase III trials and a subpopulation analysis of the ATHENA study. Prospective trials evaluating Bev combination regimens in TN breast cancer are ongoing.

Prognostic Significance of Molecular Subtypes in Male Breast Cancer

INTRODUCTIONThe relatively unfavorable outcome in male breast cancer has been attributed to more advanced local tumor stage and high incidence of lymph node invasion at the time of diagnosis. This study aimed to classify the molecular subtypes of male breast cancers based on the expression profile of immunomarkers and to evaluate their association with clinicopathological features and patients outcome.METHODSTo define molecular subtypes a total of 174 cases of male breast carcinoma were examined retrospectively using immunostains for hormone receptors (HR) and cytokeratin 5/6 (CK5/6). Human epidermal growth factor receptor 2 (HER2) expression was evaluated by immunostaining and confirmed by fluorescent in situ hybridization. Tumor characteristics and overall survival (OS) data were available and correlated with protein expression and the molecular subtype.RESULTSThe luminal A subtype (HR+/HER2-) was the most common subtype in male breast cancer (82.8%; n=144) with a median patients OS of 122 month. Luminal B tumors (HR-/HER+) were found in 6.2% (n=11), basal-like (HR-/HER2-/CK5/6+) in 9.6% (n=17) and HER2+/HR- carcinomas in 1.1% (n=2). Basal like male breast carcinoma showed a statistically significant reduced overall survival (median: 51 month; p&lt;0.01). Due to the low number of patients prognostic significance of HER2 positivity (luminal B and HER2+/HR-subtype) was not evaluable.CONCLUSIONSIn our study group, luminal A was the predominant subtype of male breast carcinoma and showed an excellent patients outcome. However, like in females tumors with a basal like subtype which were known to show minor chemotherapy response had a worse prognostic outcome. Therefore, new therapeutic options have to be defined.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2110.

Matched-pair analysis of female and male breast cancer: a comprehensive cohort study

Abstract #4129

Introduction:&#x2028; Male breast cancer (MBC) is a rare disease accounting for approximately 1% of all breast carcinomas. Due to the low incidence treatment guidelines based on prospective studies are lacking. Presently treatment recommendations are derived from the standards for female breast cancer. However, those approaches might be inadequate because of distinct gender specific differences in tumor biology of breast cancer. This study was planned in order to elucidate potential differences between female and male breast cancer in both tumor biological behavior and clinical practice.&#x2028; Patients and Methods:&#x2028; MBC diagnosed 1995-2007 (region Chemnitz/Zwickau, Saxony, Germany) was retrospectively analyzed. Tumor characteristics, treatment and follow-up of the patients were documented. In order to highlight potential differences matched-pairs of female and male breast cancer patients were created. Each MBC was matched with a female counterpart (FBC) that showed accordance in at least 5-7 tumor characteristics (age, TNM, grade, hormone receptors, HER2 stage).&#x2028; Results:&#x2028; FBC and MBC (n=113 patients each) were evaluable for this analysis. For MBC the following tumor characteristics were documented: &gt;60% advanced stages (T2-4), only 6% well differentiated, 42.5% nodal-positive, 86% hormone-sensitive (ER-positive 79.2%, PR-positive 76.9%), 6.2% HER2 positive.&#x2028; 83.2% of MBC had a mastectomy/axillary dissection (FBC 49.0%), 55% adjuvant radiotherapy (FBC 66.7%), 64% adjuvant systemic therapy (FBC 80.6%), 32.7% chemotherapy (FBC 49.5%) and 47.8% endocrine treatment (FBC 60.1%). 31% of MBC had a relapse (FBC 25.9%), 68.1% overall survival (OS) (FBC 70.4%), 98 months (FBC 76 months) median survival time. In univariate analyses reduced OS of MBC was significant associated with advanced tumor stages (p&lt;.005), poor histological grade (p&lt;.05), receptor negative (p&lt;.05) and nodal-positive tumors (p&lt;.05). Furthermore adjuvant radiotherapy showed survival benefit. However, in multivariate analysis only tumor stage showed statistical significance (p&lt;.01). Regarding these tumor characteristics no OS differences could be observed between FBC and MBC. However, MBC showed a trend to a shortened survival for receptor negative tumors in comparison to FBC (p=.055).&#x2028; Discussion:&#x2028; 1. Delayed diagnosis of MBC; 2. Our study showed more advanced and undifferentiated tumors with a high percentage of nodal positivity; 3. In our analysis these unfavorable tumor characteristics were not related to a poor OS; 4. We found no significant differences regarding disease outcome between FBC and MBC; despite of a more aggressive adjuvant treatment for FBC.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4129.

Tremor in Parkinson's disease: 24-hr monitoring with calibrated accelerometry

Monitoring systems enable the long-term registration of tremor in patients with Parkinson's disease This method is useful in the objective measurement of tremor during the course of treatments. Indeed, the symptoms of tremor as well as the aggravating and attenuating influences can be observed under real-life conditions. The methodology of data recording and analysis, described in previous investigations, was extended to automatically detect body position and certain movement patterns with calibrated 4-channel accelerometry. The main purpose of the present investigation was to apply this refined and extended methodology to patients in a clinical rehabilitation program, and to examine its practability with respect to the results of the treatment and the patients' compliance. The methodology was tested on 30 patients (17 male, 13 female) with Parkinson's disease. The mean age was 64.8 years (s = 8.9). The Hoehn-Yahr index ranged from 1 to 3 (m = 2.3, s = 0.7) and the overall UPDRS scale between 10 and 74 (m = 42.9, s = 18.1). The data recording included: (1) the registration of tremor under standardised conditions of rest and postural tremor test with and without distraction; (2) a standard protocol to obtain reference values for body position and movement; and (3) the 24-hr monitoring. 21 patients could be recorded a second time, on average 18 days after the first recording. Between the two registrations, patients received individually tailored drug treatment supplemented with specific activating physiotherapy, ergotherapy measures, and individual psychotherapeutic counseling. Changes between first and second recording were evident for the three tremor variables, but significant only for the 24-hr ambulatory monitoring. The between and within-subjects correlations of the tremor variables were rather low except the correlations between occurrence and amplitude (between-subjects. 87; within-subjects. 67). Conditions of rest and postural tremor test showed a correlation with corresponding segments of the ambulatory monitoring of about. 50 for the tremor occurrence. The best prediction of the day-time monitoring was made by the tremor tests with distraction, whereas the night segment was best predicted by the standard protocol.

Development of prosaccade and antisaccade task performance in participants aged 6 to 26 years

There are few studies on the development of oculomotor functions during childhood. B. Fischer, M. Biscaldi, and S. Gezeck (1997) reported improvement of antisaccade task performance between ages 6 and 16 years. The present study is a replication and extension of those results. In three age groups (6-7, 10-11, 18-26 years), saccades during pro- and antisaccade tasks with 200-ms gap and overlap and during a fixation task were measured. Adults exhibited faster saccades and less prosaccades during the antisaccade tasks than 10-11-year-old children; these two groups had faster saccades during all tasks and less prosaccades during the anti- and the fixation task than 6-7-year-old subjects. Both children groups made more express saccades than adults. Results suggest different degrees of age-related improvement for different saccadic parameters, the effects being greatest for prosaccade inhibition during the antisaccade task and in line with the assumed protracted development of prefrontal functions.

The gap effect in pro-saccades and anti-saccades in psychometric schizotypes

Schizophrenic patients and their first-degree relatives exhibit deficits in the anti-saccade task. In the present study, anti-saccade task performance was examined in subjects with 'high' and 'low' expressions of the schizotypal personality trait. For that purpose, the SPQ-G, the German adaptation of the Schizotypal Personality Questionnaire (SPQ; Raine, 1991), was filled in by 489 university students. Twenty and 21 participants with 'high' and 'low' SPQ-G scores, respectively, were compared with respect to saccadic eye movements elicited under the overlap and 200 ms gap conditions of the pro- and anti-saccade tasks. Each task block comprised 150 trials, 75 to either side in random order. The order of presentation of the task blocks was counterbalanced across the participants of each group. Saccadic reaction times were slower during the anti- as compared to the pro-saccade task and under the overlap as compared to the gap condition. Direction errors occurred almost exclusively during the anti-saccade task, express saccades mainly under the pro-saccadic gap condition. High-schizotypal participants did not differ significantly from low-schizotypal participants in any of these measures. While these results might suggest normal anti-saccade task performance in schizotypal personality as defined by the SPQ-G, the sampling strategy adopted in the present study is the more plausible explanation for the lack of group differences.

Motion pattern and posture: correctly assessed by calibrated accelerometers

Basic motion patterns and posture can be distinguished by multichannel accelerometry, as recently shown. A refinement of this method appeared to be desirable to further increase its effectiveness, especially to distinguish walking and climbing stairs, and body rotation during sleep. Recordings were made of 31 subjects, according to a standard protocol comprising 13 motions and postures. This recording was repeated three times with appropriate permutation. Five uni-axial sensors and three sites of placement (sternum with three axes, right and left thigh) were selected. A hierarchical classification strategy used a standard protocol (i.e., individual reference patterns) to distinguish subtypes of moving behaviors and posture. The analysis method of the actometer signals reliably detected 13 different postural and activity conditions (only 3.2% misclassifications). A minimum set of sensors can be found for a given application; for example, a two-sensor configuration would clearly suffice to differentiate between four basic classes (sitting, standing, lying, moving) in ambulatory monitoring.

24-h Assessment of Tremor Activity and Posture in Parkinson's Disease by Multi-Channel Accelerometry

Abstract This study describes a new method, based on accelerometry, which quantifies tremor activity and posture continuously. A total of 25 right-handed patients with Parkinson's disease were recorded in a rest condition and in a postural tremor test, and during 24-h ambulatory monitoring. The tremor parameters, such as amplitude, frequency, and occurrence (percent of time), were derived by joint amplitude-frequency analysis. The DC components of multi-channel accelerometry allowed the detection of posture. A repeated measurement MANOVA was used to test the effects of posture and night-day differences in tremor activity. Further issues included consistencies of amplitude measurements across hands, between tasks, and between segments of recordings. Findings indicated an increase between resting tremor and postural tremor in the three tremor parameters, an increase under distraction, and enhanced activity in sitting compared to standing/walking. The best predictions of daytime monitoring measures, based on resting measures, were made for left hand tremor. This methodology is suitable for the detection of diurnal changes in tremor activity, especially amplitude changes, and for the psychophysiological investigation of enhanced tremor caused by task demands and emotional reactions.

Joint amplitude and frequency analysis of tremor activity

Clinical tremor analysis mostly is used for the measurement of tremor frequency. The analysis is based on short segments of EMG recordings and on clinical ratings of tremor intensity. Accelerometry appears to have some practical advantages. The present study was concerned with the development of a methodology for assessing tremor activity using the three parameters, frequency (Hz), amplitude (g), and occurrence of tremor (in per cent of time). These parameters were derived from joint amplitude frequency analysis of the calibrated accelerometer raw signal and from appropriate decision rules. This methodology was used in connection with 27 patients with Parkinson's disease, to investigate the aforesaid parameters of tremor activity. Postural tremor had a higher occurrence time (right-hand only) and higher frequency (left-hand only) than resting tremor, however, the average amplitudes did not differ. The correlations between right-hand and left-hand measures were higher during postural tremor test. Frequency was not correlated to amplitude or occurrence time, however, moderate correlations did exist between amplitude and occurrence time. In addition to the assessment of tremor activity, multi-channel accelerometry may be used for the detection of posture and motion. Further applications of this methodology, for example, in 24 hr ambulatory monitoring of tremor, are discussed.