Randomized phase II trial of capecitabine versus capecitabine, low molecular weight heparin, and prednisone in refractory colorectal carcinoma

e15126

Background: Capecitabine is widely used in the treatment of advanced colorectal cancer. Continuous low dose chemotherapy has been postulated to have anti-angiogenic effects discrete from its anti-proliferative effects on tumors (metronomic therapy). Dalteparin and prednisone have also been implicated in inhibiting tumour angiogenesis and hypothesized to have additive benefit to chemotherapy. This randomized phase II study examined the additive effect of dalteparin and prednisone with capecitabine in metastatic colorectal cancer. Methods: Patients with metastatic colorectal cancer were randomized to either capecitabine (C) 2,500 mg/m2 in divided doses from days 1–14 in a 3-week cycle or capecitabine with dalteparin and prednisone (CDP). There was no restriction on previous treatment, other than no prior capecitabine. Dalteparin was given at 5,000 units once daily subcutaneously, and prednisone orally 10 mg daily, both on a continuous basis. Thirty patients were planned for accrual in each arm with interim analysis when accrual reached fifteen in each arm. The primary end-point was disease control defined as treatment response or stable disease >4 months. Radiological evaluation was performed every 6 weeks. Treatment was discontinued if patients had progressive disease or intolerable toxicity. Results: Thirty patients were recruited. Fourteen patients had received ≥3 previous regimens (median 3 (C), 2 (CDP)). Median performance statuses were ECOG 1 (C) and 0 (CDP). Nine patients achieved stable disease greater than 6 months (5 (C)/4 (CDP)). There was no statistical difference in the median survival time and time-to- progression for the two groups (11.1 mth (C)/15.8 mth (CDP); 3.2 mth (C)/2.8 mth (CDP)). The commonest toxicities overall were myelosuppression and hand-foot syndrome (HFS). The most common Grade 3+ adverse events were HFS (6 patients) and diarrhea (4 patients). Conclusions: The combination of dalteparin, prednisone and capecitabine did not improve disease control over that seen with capecitabine in refractory metastatic colorectal cancer.

No significant financial relationships to disclose.

ESPAC-3(v2): A multicenter, international, open-label, randomized controlled phase III trial of adjuvant 5-fluorouracil/folinic acid (5-FU/FA) versus gemcitabine (GEM) in patients with resected pancreatic ductal adenocarcinoma

LBA4505

The full, final text of this abstract will be available in Part II of the 2009 ASCO Annual Meeting Proceedings, distributed onsite at the Meeting on May 30, 2009, and as a supplement to the June 20, 2009, issue of the Journal of Clinical Oncology.

[Table: see text]

A review of the patterns of docetaxel use for hormone refractory prostate cancer (HRPC) at the Princess Margaret Hospital

e16161

Background: Docetaxel is standard of care for the treatment of HRPC, based on two large randomized clinical trials. The aim of this study was to determine if docetaxel use and effectiveness in routine clinical practice was similar to that seen in the TAX 327 randomized phase III clinical trial. Methods: A retrospective chart review was undertaken to assess patterns of docetaxel use for HRPC at our institution for the 2-year period since its approval for the first-line treatment of HRPC in 2005. Results: Eighty-eight patients, median age 71 and baseline PSA 107, received docetaxel in the first line setting. Main reasons for initiating docetaxel were rising PSA (90%) and progressive symptoms (71%). Eighteen percent of patients received docetaxel for rising PSA alone. A median of 7 cycles was administered. PSA response rates were 61%, time to response 1.5 months, and response duration 6.8 months. Disease progression was the most common reason for treatment discontinuation (36%). Main toxicities were fatigue (32%) and neuropathy (22%). Kaplan Meier survival analysis showed median duration of survival was 15.9 months (95% CI 12.4–20.5) from first drug use. 1-year survival was 0.63 (95% CI 0.52–0.72). Post-docetaxel, 36 patients received second-line treatment, mostly with mitoxantrone (89%). Second-line response rates were 22%, and median duration of response was 4 months. Conclusions: In routine clinical practice, docetaxel is a well-tolerated regimen for the treatment of HRPC. Response rates and toxicity profiles were comparable to the randomized trials. However, compared with the TAX 327 clinical trial, survival was slightly shorter than expected (15.9 vs. 18.9 months), possibly due to inclusion of patients with poorer performance status and comorbidities, who may be excluded from clinical trials. Second-line response rates were also comparable with previous reports.

No significant financial relationships to disclose.

Adjuvant 5-fluorouracil and folinic acid vs observation for pancreatic cancer: composite data from the ESPAC-1 and -3(v1) trials

The ESPAC-1, ESPAC-1 plus, and early ESPAC-3(v1) results (458 randomized patients; 364 deaths) were used to estimate the effectiveness of adjuvant 5FU/FA vs resection alone for pancreatic cancer using meta-analysis. The pooled hazard ratio of 0.70 (95% CI=0.55-0.88) P=0.003, and the median survival of 23.2 (95% CI=20.1-26.5) months with 5FU/FA vs 16.8 (95% CI=14.3-19.2) months with resection alone supports the use of adjuvant 5FU/FA in pancreatic cancer.

A phase I study of tipifarnib combined with conventional induction and consolidation therapy for previously untreated patients with acute myeloid leukemia aged 60 years and over

Patients aged 60 years and over with previously untreated acute myeloid leukemia were enrolled in a Phase I study combining tipifarnib with standard induction therapy. The regimen consisted of cytarabine 100 mg/m(2)/day continuous intravenous (i.v.) infusion on days 1-7, daunorubicin 60 mg/m(2)/day i.v. push x 3 on days 6-8 and tipifarnib twice daily on days 6-15. Tipifarnib was escalated over four dose levels (200, 300, 400 and 600 mg). Patients achieving complete response (CR) were eligible to receive one consolidation using the same regimen. The following dose-limiting toxicities (DLTs) were identified during induction: dose level I: 2/6 (hyperbilirubinemia, respiratory arrest), level II: 0/3, level III: 0/3 and level IV: 4/10 (one each of diarrhea, neutropenic enterocolitis, arrhythmia and delayed hematologic recovery post-consolidation). There were no DLTs due to delayed hematologic recovery post-induction. Of 22 evaluable patients, there were 10 CR, 2 morphologic leukemia-free state (MLFS), 2 partial remission (PR) and 8 non-responders. Of seven patients with adverse risk cytogenetics, there were four CR/MLFS and one PR. In summary, this regimen was well tolerated and the maximum tolerated dose was not reached, although somewhat more severe gastrointestinal toxicity was seen at dose level IV. Tipifarnib 600 mg b.i.d. is considered the recommended dose for further study using this regimen.

A focal-spot diagnostic for on-shot characterization of high-energy petawatt lasers

An on-shot focal-spot diagnostic for characterizing high-energy, petawatt-class laser systems is presented. Accurate measurements at full energy are demonstrated using high-resolution wavefront sensing in combination with techniques to calibrate on-shot measurements with low-power sample beams. Results are shown for full-energy activation shots of the OMEGA EP Laser System.

AtCHX13 is a plasma membrane K+ transporter

Potassium (K+) homeostasis is essential for diverse cellular processes, although how various cation transporters collaborate to maintain a suitable K+ required for growth and development is poorly understood. The Arabidopsis (Arabidopsis thaliana) genome contains numerous cation:proton antiporters (CHX), which may mediate K+ transport; however, the vast majority of these transporters remain uncharacterized. Here, we show that AtCHX13 (At2g30240) has a role in K+ acquisition. AtCHX13 suppressed the sensitivity of yeast (Saccharomyces cerevisiae) mutant cells defective in K+ uptake. Uptake experiments using (86)Rb+ as a tracer for K+ demonstrated that AtCHX13 mediated high-affinity K+ uptake in yeast and in plant cells with a K(m) of 136 and 196 microm, respectively. Functional green fluorescent protein-tagged versions localized to the plasma membrane of both yeast and plant. Seedlings of null chx13 mutants were sensitive to K+ deficiency conditions, whereas overexpression of AtCHX13 reduced the sensitivity to K+ deficiency. Collectively, these results suggest that AtCHX13 mediates relatively high-affinity K+ uptake, although the mode of transport is unclear at present. AtCHX13 expression is induced in roots during K+-deficient conditions. These results indicate that one role of AtCHX13 is to promote K+ uptake into plants when K+ is limiting in the environment.

Response of Butternut Selections to Inoculation with Sirococcus clavigignenti-juglandacearum

Butternut trees (Juglans cinerea) clonally propagated via grafting from source trees with putative resistance to butternut canker were inoculated monthly with two isolates of Sirococcus clavigignenti-juglandacearum in a field planting in Minnesota. Significant differences in resulting canker length were found among (i) month of inoculation, (ii) accession, and (iii) isolate. Results support the suggestion that canker-free butternut occasionally found growing among butternut severely affected by butternut canker potentially have disease resistance and may have value for genetic conservation and restoration of the species. Developing an effective resistance screening technique will require additional information on the natural infection process and testing under various climatic conditions across the range of butternut.

The protection of wildlife from mortality: hypothesis and results for risk assessment

Wildlife deaths associated with cyanide-bearing tailings dams are a significant environmental issue that has affected the gold mining industries for many years and still characterized by little knowledge about how to measure, monitoring, reduce or eliminate those deaths. The purpose of this paper is statistically to determine: the potential for establishing causal relations between exposure to cyanide (in its most common species relevant to tailings) and response (measured by death counts), to develop a protocol of data analysis, the understanding of the significance of data gaps, and the effect of likely risk management interventions to achieve the goals of the International Cyanide Management Code (ICMC); [ICMC The International Cyanide Management Institute. International cyanide management code, the international cyanide management institute 2005, www.cyanidecode.org.]. However, operator's certification under the ICMC is difficult because of the limited data and potentially serious under-estimation of the death counts. This is due to observational skill and monitoring frequency, the small size of the carcasses, large extent of tailings facilities, carcasses loss by; entombment in tailings, sink, or taken by scavenging wildlife. This (1st order or bounding) assessment results focus on bird-deaths, which appear to be most frequent at sites where elevated cyanide concentrations are found. Those results indicate that the empirical causal associations we generate support the hypotheses that: This paper also develops the basis for a complete risk assessment study to be based on additional data gathering activities and detailed statistical analyses. These two activities, combined with a risk management plan also being developed, will provide a tool for compliance with the ICMC.

The diagnosis and management of rectal cancer: expert discussion and recommendations derived from the 9th World Congress on Gastrointestinal Cancer, Barcelona, 2007

Knowledge of the biology and management of rectal cancer continues to improve. A multidisciplinary approach to a patient with rectal cancer by an experienced expert team is mandatory, to assure optimal diagnosis and staging, surgery, selection of the appropriate neo-adjuvant and adjuvant strategy and chemotherapeutic management. Moreover, optimal symptom management also requires a dedicated team of health care professionals. The introduction of total mesorectal excision has been associated with a decrease in the rate of local failure after surgery. High quality surgery and the achievement of pathological measures of quality are a prerequisite to adequate locoregional control. There are now randomized data in favour of chemoradiotherapy or short course radiotherapy in the preoperative setting. Preoperative chemoradiotherapy is more beneficial and has less toxicity for patients with resectable rectal cancer than postoperative chemoradiotherapy. Furthermore chemoradiotherapy leads also to downsizing of locally advanced rectal cancer. New strategies that decrease the likelihood of distant metastases after initial treatment need be developed with high priority. Those involved in the care for patients with rectal cancer should be encouraged to participate in well-designed clinical trials, to increase the evidence-based knowledge and to make further progress. Health care workers involved in the care of rectal cancer patients should be encouraged to adopt quality control processes leading to increased expertise.

Doses to critical organs following radiotherapy and concomitant imaging of the larynx and breast

The development of conformal radiotherapy carries with it the implication of an increased number of imaging procedures at various stages throughout the overall treatment, principally for verification at some, or all, of the treatment fractions. This raises the issue of the balance between the benefit of these additional imaging exposures and the associated risk of radiocarcinogenesis arising from them. As such, it is necessary to appreciate the doses to critical organs for which individual carcinogenic risks have been estimated. In this study, doses to these organs have been measured with lithium fluoride thermoluminescence dosimetry loaded in anthropomorphic phantoms and subjected to realistic radiotherapy treatments of the larynx and breast, including concomitant CT and electronic portal imaging exposures associated with localization and verification of these treatments. Even for large numbers of concomitant images of either modality, arising from imaging at every fraction, the leakage and scatter from the radiotherapy itself is shown to dominate the overall organ dose, with imaging procedures generally contributing 5-20% of the total organ dose.

An emerging cyberinfrastructure for biodefense pathogen and pathogen-host data

The NIAID-funded Biodefense Proteomics Resource Center (RC) provides storage, dissemination, visualization and analysis capabilities for the experimental data deposited by seven Proteomics Research Centers (PRCs). The data and its publication is to support researchers working to discover candidates for the next generation of vaccines, therapeutics and diagnostics against NIAID's Category A, B and C priority pathogens. The data includes transcriptional profiles, protein profiles, protein structural data and host-pathogen protein interactions, in the context of the pathogen life cycle in vivo and in vitro. The database has stored and supported host or pathogen data derived from Bacillus, Brucella, Cryptosporidium, Salmonella, SARS, Toxoplasma, Vibrio and Yersinia, human tissue libraries, and mouse macrophages. These publicly available data cover diverse data types such as mass spectrometry, yeast two-hybrid (Y2H), gene expression profiles, X-ray and NMR determined protein structures and protein expression clones. The growing database covers over 23 000 unique genes/proteins from different experiments and organisms. All of the genes/proteins are annotated and integrated across experiments using UniProt Knowledgebase (UniProtKB) accession numbers. The web-interface for the database enables searching, querying and downloading at the level of experiment, group and individual gene(s)/protein(s) via UniProtKB accession numbers or protein function keywords. The system is accessible at http://www.proteomicsresource.org/.

Radiological features of progressive tumoral calcinosis in chronic renal failure

We present the case of a young adult patient with chronic renal failure who developed painful subcutaneous nodules after failed renal transplant and recommencing dialysis. These nodules were juxta-articular in location and initially located over both shoulders. Radiological evaluation suggested tumoral calcinosis. The patient was placed on a strict dialysis and dietary regimen but was suboptimally compliant with same. The patient developed progressive disease with an increase in size and number of juxta-articular calcified soft-tissue masses. However, 6 months following a second renal transplant clinical and radiological follow up demonstrated marked resolution both in symptomatology and radiographic findings. We present the plain radiographic, CT and MRI findings which demonstrate the typical radiological features of tumoral calcinosis. We correlate these findings with clinical course and histological findings following surgical excision of one of these masses.

A phase II study of sorafenib in patients with chemo-naive castration-resistant prostate cancer

BACKGROUND

The purpose of this trial was to evaluate the antitumor activity of sorafenib, a multikinase inhibitor of cell proliferation and angiogenesis, in patients with castration-resistant prostate cancer.

PATIENTS AND METHODS

This was a multicenter, two-stage, phase II study. Sorafenib 400 mg was administered orally twice daily continuously. Primary end point was prostate-specific antigen (PSA) 'response' defined as a > or =50% decrease for > or =4 weeks.

RESULTS

In all, 28 patients were enrolled. Eastern Cooperative Oncology Group performance status was zero or one in 19 and 9 patients. Two patients had no metastases, and 26 had bone and/or lymph node disease. A median of two cycles (range 1-8) was delivered. Adverse events were typical for sorafenib. The PSA response rate was 3.6% [95% confidence interval (CI) 0.1% to 18.3%] with response occurring in one patient (baseline = 10 000 and nadir = 1643 microg/l). No measurable disease responses occurred in eight patients. Time to PSA progression was 2.3 months (95% CI 1.8-6.4). Of 16 patients who discontinued sorafenib and then did not receive any immediate therapy, 10 had postdiscontinuation PSA declines of 7%-52%.

CONCLUSIONS

Sorafenib has limited activity using current PSA criteria. The declines in PSA observed on treatment discontinuation indicate an effect on PSA production/secretion. Further study may be warranted but needs to consider the limitations of PSA as an indicator of progression and response.

The management of pancreatic cancer. Current expert opinion and recommendations derived from the 8th World Congress on Gastrointestinal Cancer, Barcelona, 2006

This article summarizes the expert discussion on the management of pancreatic cancer, which took place during the 8th World Congress on Gastrointestinal Cancer in June 2006 in Barcelona. A multidisciplinary approach to a patient with pancreatic cancer is essential, in order to guarantee an optimal staging, surgery, selection of the appropriate (neo-)adjuvant strategy and chemotherapeutic choice management. Moreover, optimal symptomatic management requires a dedicated team of health care professionals. Quality control of surgery and pathology is especially important in this disease with a high locoregional failure rate. There is now solid evidence in favour of chemotherapy in both the adjuvant and palliative setting, and gemcitabine combined with erlotinib, capecitabine or platinum compounds seems to be slightly more active than gemcitabine alone in advanced pancreatic cancer. There is a place for chemoradiotherapy in selected patients with locally advanced disease, while the role in the adjuvant setting remains controversial. Those involved in the care for patients with pancreatic cancer should be encouraged to participate in well-designed clinical trials, in order to increase the evidence-based knowledge and to make further progress.

A critical review of the effects of gold cyanide-bearing tailings solutions on wildlife

Wildlife deaths associated with cyanide-bearing mine waste solutions have plagued the gold mining industries for many years, yet there is little published data showing the relationship between wildlife mortality and cyanide toxicity. A gap of knowledge exists in monitoring, understanding the causal relationships and managing risks to wildlife from cyanide-bearing waste solutions and tailings. There is a need for the gold industry to address this issue and to meet the International Cyanide Management Code (ICMC) guidelines. The perceived extent of the issue varies, with one study finding the issue inadequately monitored and wildlife deaths grossly underestimated. In Nevada, USA during 1990 and 1991, 9512 carcasses were reported of over 100 species, although there was underestimation due to reporting being voluntary. Of these, birds comprised 80-91% of vertebrate carcasses reported annually. At Northparkes, Australia in 1995, it was initially estimated that 100 bird carcasses were present by mine staff following a tailings incident; when a thorough count was conducted, 1583 bird carcasses were recorded. Eventually, 2700 bird deaths were documented over a four-month period. It is identified that avian deaths are usually undetected and significantly underestimated, leading to a perception that a risk does not exist. Few guidelines and information are available to manage the risks of cyanide to wildlife, although detoxification, habitat modification and denying wildlife access have been used effectively. Hazing techniques have proven ineffective. Apparently no literature exists that documents accurate wildlife monitoring protocols on potentially toxic cyanide-bearing mine waste solutions or any understanding on the analysis of any derived dataset. This places the onus on mining operations to document that no risk to wildlife exists. Cyanide-bearing tailings storage facilities are environmental control structures to contain tailings, a standard practice in the mining industry. Cyanide concentrations below 50 mg/L weak-acid-dissociable (WAD) are deemed safe to wildlife but are considered an interim benchmark for discharge into tailings storage facilities (TSFs). Cyanide is a fast acting poison, and its toxicity is related to the types of cyanide complexes that are present. Cyanide in biota binds to iron, copper and sulfur-containing enzymes and proteins required for oxygen transportation to cells. The accurate determination of cyanide concentrations in the field is difficult to achieve due to sampling techniques and analytical error associated with loss and interferences following collection. The main WAD cyanide complexes in gold mine tailings are stable in the TSF environment but can release cyanide ions under varying environmental conditions including ingestion and absorption by wildlife. Therefore distinction between free, WAD and total cyanide forms in tailings water for regulatory purposes is justified. From an environmental perspective, there is a distinction between ore bodies on the basis of their copper content. For example, wildlife deaths are more likely to occur at mines possessing copper-gold ores due to the formation of copper-cyanide complexes which is toxic to birds and bats. The formation of copper-cyanide complex occurs preferentially to gold cyanide complex indicating the relative importance of economic vs. environmental considerations in the tailings water. Management of cyanide to a perceived threshold has inherent risks since cyanide has a steep toxicity response curve; is difficult to accurately measure in the field; and is likely to vary due to variable copper content of ore bodies and ore blending. Consequently, wildlife interaction needs to be limited to further reduce the risks. A gap in knowledge exists to design or manage cyanide-bearing mine waste solutions to render such facilities unattractive to at-risk wildlife species. This gap may be overcome by understanding the wildlife behaviour and habitat usage of cyanide-bearing solutions.

Development of an implantable oximetry-based organ perfusion sensor

A sensor system enabling real-time monitoring of organ perfusion following transplantation is presented. This system uses a three wavelength oximetry-based approach. The instrument is intended for implantation at the organ site during transplantation to provide real-time reporting of the perfusion status of the tissue for 7-10 days following the procedure. Data is transmitted from the sensor to a localized receiver using direct sequence spread spectrum techniques at 916 MHz. In this paper, the sensing method and associated electronics implementation are presented. The present status of system miniaturization is summarized along with plans for future miniaturization efforts. Preliminary sensor data is presented demonstrating the efficacy of the technique.

Blood-brain barrier impairment in Alzheimer disease: stability and functional significance

OBJECTIVE

To determine the stability and functional significance of blood-brain barrier (BBB) integrity in patients with mild to moderate Alzheimer disease (AD).

METHODS

Thirty-six patients (mean age 71 +/- 7 years) with mild to moderate AD (Mini-Mental State Examination [MMSE] 19 +/- 5) participated in a biomarker study involving clinical assessments, brain imaging, and CSF and plasma collection over 1 year. BBB integrity was assessed with the CSF-albumin index (CSF-AI).

RESULTS

BBB disruption was present in an important subgroup of patients (n = 8/36, 22%) at all time points measured. CSF-AI was highly reproducible over 1 year with an intraclass correlation of 0.96. Age, sex, and APOE status did not correlate with CSF-AI. Vascular factors (blood pressure, Hachinski ischemia score, MR-derived white matter hyperintensity, body mass index) were not strongly associated with CSF-AI levels (p = 0.066). CSF/plasma IgG ratio correlated with CSF-AI in a manner indicating that peripheral IgG has greater access to the CNS in patients with an impaired BBB. Further evidence for the physiologic significance of the CSF-AI was noted in the form of correlations with rates of disease progression, including annual change on MMSE (r(2) = 0.11, p = 0.023), annual Clinical Dementia Rating sum-of-boxes change (r(2) = 0.29, p = 0.001), and annual ventricular volume change (r(2) = 0.17, p = 0.007).

CONCLUSIONS

Blood-brain barrier (BBB) impairment is a stable characteristic over 1 year and present in an important subgroup of patients with Alzheimer disease. Age, gender, APOE status, vascular risk factors, and baseline Mini-Mental State Examination score did not explain the variability in BBB integrity. A role for BBB impairment as a modifier of disease progression is suggested by correlations between CSF-albumin index and measures of disease progression over 1 year.

Sorafenib for the treatment of metastatic renal cancer (MRC) in the real world: The Princess Margaret Hospital (PMH) experience

15568

Background: Sorafenib, an oral multi-kinase inhibitor, prolonged progression free survival (PFS) of MRC patients (pts) in second line when compared to placebo in a phase III trial (Escudier at al ECCO 2005). Grade 3/4 adverse events (AE) were reported in 12% of pts. Here we present sorafenib’s efficacy and safety in a less selected cohort of pts enrolled in the Bayer Expanded Access Program at PMH. Methods: Pts with MRC received Sorafenib 400 mg bid continuously until disease progression (PD) and/or clinical deterioration..Tumor response was measured by RECIST criteria. AE were graded by NCI common toxicity criteria. Summary statistics and logistic regression were used to describe the results. Results: From Nov 2005 to Aug 2006, 58 pts were enrolled: median age was 59 years (range 14–86), 47 (81%) were male, 48 (83%) had clear cell histology and 46 (79%) received Sorafenib in first line. None received prior kinase-inhibitors. Using the Motzer Prognostic Index, 29 pts (50%) were low risk, 21 (36%) intermediate and 8 (14%) poor risk. Grade 3/4 AE occurred in 37 pts (64%, 95% CI 50–76%): 15 (26%) pts had skin rash, 10 (17%) hand-foot syndrome, 4 (7%) hypertension, 4 (7%) fatigue, and 4 (7%) diarrhea. Thirty-six (62%) pts required dose reductions and/or treatment interruptions, most due to skin reactions and hand-foot syndrome. Median follow-up was 9 months (IQR range 2–11), the median PFS was 7.5 months (IQR range 5.4–11.3), and the best responses among 56 evaluable pts were: 10 (17%) confirmed partial responses (median duration: 6 months, range 4–11), 14 (24%) stable diseases for = 6 months and 10 (18%) early progression. Pts with bony mets progressed earlier than pts without bony mets. Abnormal creatinine clearance, age, performance status, line of treatment and presence of significant comorbid conditions were not associated with grade 3/4 AE in univariate analysis. Conclusions: Sorafenib is effective in a ”real world”, less selected patient population with MRC but leads to more toxicity than described previously.

[Table: see text]

Quality of life in patients with advanced colorectal cancer treated with cetuximab: Results of the NCIC CTG and AGITG CO.17 trial

4002

Background: Cetuximab prolongs survival in pretreated advanced colorectal cancer (CRC) patients (pts). For these pts, the effect of palliative treatment on quality of life (QOL) is also an important outcome. Methods: CO.17 was a randomized controlled trial (n=572) of cetuximab combined with best supportive care (BSC) vs BSC alone in pts with pretreated epidermal growth factor receptor-positive advanced CRC. Primary endpoint was survival. QOL was a secondary endpoint using the EORTC QLQ-C30 at baseline, 4, 8, 16, and 24 weeks (wks). Primary endpoint for QOL compared physical function (PF) and global health status (Global) mean changes from baseline to 8 and 16 wks using Wilcoxon test. Negative change scores denote worsening QOL. The proportion of pts in either arm with at least a 10 unit deterioration at 8 and 16 wks from baseline was compared using Fischer’s exact test. Kaplan-Meier estimates and logrank tests on median time to definitive QOL deterioration, defined as at least a 10 unit deterioration in PF or Global, were evaluated. Exploratory analyses of all other scale and symptom change scores at 8 and 16 wks were also performed. Results: Compliance rates for QOL questionnaires was high at baseline, 94% each arm, but did drop off over time: 73% vs 60% at week 8 and 60% vs 39% at week 16 for cetuximab vs BSC, respectively. PF change scores at 8 wks were -3.9 for cetuximab vs -8.6 for BSC (p=.046); at 16 wks -5.9 vs -12.5 (p=.027). Global change scores were -0.5 vs -7.1 (p=.008) and -3.6 vs -15.2 (p=.008) at 8 and 16 wks respectively. The proportion of pts with deteriorating PF was 25% for cetuximab vs 35% for BSC at 8 wks (p=.051) and 30 vs 43% at 16 wks (p=.069). Deteriorating Global was seen in 23 vs 38% at 8 wks (p=.004) and 31 vs 49% at 16 wks (p=.0011). Time to PF deterioration was 5.4 months [95% CI 3.8–5.7] for cetuximab vs 3.7 months [2.0–3.9] for BSC (p=.022). Time to Global deterioration was 5.4 [3.9–5.7] vs 3.7 months [2.1–3.9] (p=.062). Exploratory analyses of all other scale and symptom change scores at 8 and 16 wks showed all differences of p<.05 also favored cetuximab. Conclusions: Cetuximab provides palliation in pretreated pts with advanced CRC, delaying deterioration in QOL as well as improving survival.

[Table: see text]

Final results of CONFIRM 2: A multinational, randomized, double-blind, phase III study in 2nd line patients (pts) with metastatic colorectal cancer (mCRC) receiving FOLFOX4 and PTK787/ZK 222584 (PTK/ZK) or placebo

4033

Background: PTK/ZK, a novel, oral, anti-angiogenic compound that inhibits all VEGF receptors has been investigated in two multinational randomized phase 3 studies in 1st (CONFIRM 1) and 2nd line (CONFIRM 2) mCRC. Interim analyses (IA) have been presented at ASCO 2005 and 2006, respectively. Methods: In CONFIRM 2, 855 pts were randomized to FOLFOX4 plus PTK/ZK (1250 mg, qd), or placebo. Eligibility included histologically documented mCRC, pre-treatment for metastatic disease with irinotecan-/fluoropyrimidine- based therapy, measurable disease by RECIST, PS of 0–2 and adequate organ function. Pts were stratified based on PS (0 vs. 1–2) and baseline serum Lactate Dehydrogenase (LDH = vs. >1.5 × ULN). The primary endpoint is overall survival (OS). Secondary endpoints included OS and PFS in high LDH pts (LDH > 1.5 × ULN). Results: At the time of IA in July 2005, OS was 12.1 mo in the PTK/ZK and 11.8 mo in the placebo arm (HR: 0.94; p=0.511). PFS was significantly longer in the PTK/ZK arm (5.5 mo vs. 4.1 mo; HR: 0.83; p=0.026). LDH, a marker for poor prognosis in mCRC, is predictive of the outcome in the PTK/ZK arm. When treated with PTK/ZK, high LDH pts showed a strong improvement in PFS (5.6 mo vs. 3.8 mo; HR: 0.63; p<0.001) and in OS (9.6 mo vs. 7.5 mo; HR: 0.78; p=0.10). Adverse events (AE) were similar to that of the CONFIRM 1 trial. Final analysis for OS, PFS and safety is planned for Feb. 2007 after 732 events (compared to 413 in the IA) and will be presented at the meeting. Conclusions: While the primary endpoint for OS was not met in the IA, PTK/ZK improves PFS significantly in the overall population, and shows strong activity (improved PFS and OS) in patients with high baseline serum LDH. Final results of the study will be presented at the meeting.

No significant financial relationships to disclose.

Natural and Experimental Host Range of Sirococcus clavigignenti-juglandacearum

The fungus Sirococcus clavigignenti-juglandacearum causes butternut canker in North America and is not known to kill or seriously affect tree species other than butternut (Juglans cinerea). However, this putative exotic pathogen has been found on branches of black walnut (J. nigra) and heartnut (J. ailantifolia var. cordiformis), raising questions regarding the potential host range of the pathogen and its spread to new areas on tree hosts other than butternut. Results of artificial inoculations of several hardwood species indicated that the pathogen, although not causing lethal cankers, has the ability to colonize and survive in the wood of several genera, including Quercus, Carya, Corylus, Prunus, and Castanea. Several commercially important Persian walnut (J. regia) cultivars tested were moderately or highly susceptible, underscoring the importance of preventing the movement of the pathogen into commercial Juglans plantations in California, where its ability to cause disease and damage trees is unknown. Evidence for the presence of variation in aggressiveness among isolates of S. clavigignenti-juglandacearum was detected based on differences in canker lengths resulting from inoculations with two isolates of the pathogen. In a field test of several previously named butternut cultivars, all were found to be highly susceptible to the disease, calling into question the value of these selections for nut production or future restoration uses.

Food motivated behavior of melanocortin-4 receptor knockout mice under a progressive ratio schedule

Melanocortin-4 receptor knockout (MC4RKO) mice are hyperphagic and develop obesity under free feeding conditions. We reported previously that MC4RKO mice did not maintain hyperphagia and as a result lost weight when required to press a lever to obtain food on a fixed ratio procurement schedule. To assess the generality of this result, we tested MC4RKO mice and their heterozygous and wild type littermates using progressive ratio (PR) schedules that are believed to be sensitive indicators of motivation. Mice lived in operant chambers and obtained all of their food (20mg pellets) via lever press responding. Food was available according to a PR schedule so that within a meal, food became progressively more costly, and we expected this would provide a stringent test of mechanisms controlling meal size. The schedule reset after either 3 or 20min of no responding, so defining meals, and the highest ratio completed before the reset was defined as the breakpoint. The average daily number of meals was lower and mean size of meals was higher at the 20 compared with the 3min reset condition. Mean daily food intake did not differ between the two reset criteria but did differ as a function of genotype, with MC4RKO mice eating about 25% more than heterozygous or wild type mice. Hyperphagia in the MC4RKO mice was characterized primarily by larger meals (higher breakpoints) and they emitted about twice as many responses as wild type mice. Thus, using a PR schedule, MC4RKO mice exhibit hyperphagia, and show a high level of motivation to support large meal sizes.

Humidified air inhalation for treating croup

BACKGROUND

Croup (laryngotracheobronchitis) is a common cause of upper airway obstruction in children with a peak incidence of 60 per 1000 child years in those aged between one and two years. It is characterised by hoarseness, a barking cough, and inspiratory stridor. These symptoms are thought to occur as a result of oedema of the larynx and trachea, which have been triggered by a recent viral infection. Para influenza virus type 1 is the agent most commonly identified in cases of croup. Severe cases are admitted to hospital and steroid treatment is established to reduce disease severity. Treatment with humidified air was previously widely used and is still commonly recommended as home treatment.

OBJECTIVES

To assess the efficacy of humidified air in the treatment of croup.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2005), MEDLINE (1966 to January 2006) and EMBASE (1990 to January 2006).

SELECTION CRITERIA

Randomised controlled trials (RCTs) involving children suffering from croup treated with humidified air.

DATA COLLECTION AND ANALYSIS

Two authors independently identified potentially relevant abstracts identified from the search and then assessed the full papers for inclusion and methodological quality. Outcome measures included mortality, ventilation, admission to hospital, re-contact with medical services, number of days off school and relief of symptoms; these were separately analysed for the week following treatment. Data extraction was performed by the two authors then entered by one and checked by the second author. Missing data were obtained from trails authors where possible. Data were analysed using Review Manager version 4.2. Sensitivity and sub-group analysis were not possible due to the paucity of trials.

MAIN RESULTS

Three studies in emergency settings provided data on 135 patients with moderate croup for the main outcome (croup score). The combined results from 20 to 60 minutes in the three studies marginally favoured the treatment group with a weighted standardised mean difference of -0.14 (95% confidence interval (CI) -0.75 to 0.47). No other outcomes were significantly different between the groups.

AUTHORS' CONCLUSIONS

The croup score of children managed in an emergency setting with mild to moderate croup probably does not improve greatly with inhalation of humidified air. Further research is needed in primary care settings, using a wider range of more sensitive outcome measures.

A phase I study of axitinib (AG-013736), a potent inhibitor of VEGFRs, in combination with gemcitabine (GEM) in patients (pts) with advanced pancreatic cancer

13092

Background: Axitinib (AG-013736) is a novel small molecule inhibitor of the receptor tyrosine kinases with picomolar potency against VEGFR 1, 2 & 3 and nanomolar potency against PDGFR-beta and KIT. A phase I study in solid tumors identified 5 mg BID as the therapeutic dose; a phase II study in renal cell cancer demonstrated significant efficacy with a response rate (RR) of 46% (Rini et al, ASCO 2005). This study examined the safety, PK and preliminary efficacy of AG-013736 (AG) in combination with gemcitabine (GEM) as first-line therapy for advanced pancreatic cancer. Methods: A randomized phase II study was preceded by a phase I component. All patients (pts) in the phase I portion received 1000 mg/m2 GEM by 30-minute infusion on days 1, 8, and 15 followed by one week of rest from treatment. AG 5 mg p.o. BID was given beginning Cycle 1, Day 3 (C1D3). Eligible pts had no prior chemotherapy for advanced disease, ECOG 0–2, and no previous treatment with VEGF/VEGFR inhibitors, or anti-angiogenesis treatment. Full PK profiles were collected on C1D1 (GEM alone), C1D14 (steady state, AG alone), and C1D15 (GEM + AG). In the phase II trial, pts are randomized to AG or AG plus GEM beginning C1D1. Results: 8 pts were treated on the phase I portion of this trial. Toxicity: The primary Gr. 3/4 toxicity was hematologic: Gr. 4 anemia and Gr.3 thrombocytopenia in 1 pt and Gr. 3 neutropenia in 1 pt requiring a dose reduction for GEM in Cycle 3. Gr. 2 non-hematologic adverse events include pruritus (1 pt), abdominal pain (2 pts), epigastric pain (1 pt), melena (1 pt), and asthenia (2 pts). Gr. 2 hypertension was observed in 3 pts. Efficacy: Radiological assessment suggests 2 pts with partial response and 4 pts with stable disease: response assessments are ongoing. The median number of cycles is 3 [1,6]. Treatment for 4 pts is still ongoing: Cycle 6 (2 pts) and Cycle 2 (2 pts). Conclusions: This combination is safe and appears to be an effective treatment for advanced pancreatic cancer with significant tumor regression observed in 2 pts. Therapy was well tolerated with manageable toxicity. Additional investigation of AG-013736 in combination with GEM in the phase II setting for advanced pancreatic cancer is warranted.

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A randomized phase II study of bevacizumab (B) and gemcitabine (G) plus cetuximab (C) or erlotinib (E) in patients (pts) with advanced pancreatic cancer (PC): A preliminary analysis

4040

Background: In a phase II trial of G + anti-VEGF antibody B in 52 PC pts, we reported a 21% response rate and median survival of 8.8 months (mo) (Kindler, JCO 2005). EGFR inhibitors C and E also have activity in PC. VEGF and EGFR pathways are interdependent; dual inhibition may be synergistic. Methods: We are conducting a multi-center, randomized phase II trial of GBC vs. GBE in advanced PC pts who have: no prior therapy for metastatic disease, PS 0–2, measurable disease, no tumor invasion of duodenum, no bleeding risk. Primary endpoint: response. Trial design: 2 parallel, Simon 2-stage designs; requires 6 responses in 27 evaluable pts for 2nd stage; 63 pts/arm. All pts receive G 1000 mg/m2 over 30 minutes days (D) 1, 8, 15 Q28D; B 10 mg/kg D 1, 15 Q28D. Pts are randomized to C 400 mg/m2 D1, then 250 mg/m2 Q7D, or E 150 mg D1–5, 8–12, 15–26 Q28D. CT scans: Q2 cycles. 58 pts enrolled at 13 sites 9/04–12/05. Pt characteristics: male 66%; median age 61 (range 36–82); PS: 0/1/2: 52%/40%/8%; stage IV 95%; liver metastases 76%. Results: 49 pts (GBC/GBE 24/25) are evaluable for toxicity; 51 pts (27/24) for response. 232 cycles were administered (median 4, range 1–11). Grade ¾ toxicity (%pts GBC/GBE): neutropenia 29%/28%; anemia 4%/16%, thrombocytopenia 8%/24%, DVT-PE 17%/8%, CVA 4%/4%, GI bleed 4%/12%, hypertension 4%/4%, rash 13%/4%, pneumonitis 0%/8%, diarrhea 4%/4%; grade 5: bowel perforation 0%/4%, MI- CVA 0%/4%, other cardiac 4%/0%. Response: GBC 19% (1 complete, 4 partial), GBE 21% (5 partial). Stable disease 59%/67%. Median progression-free survival 3.6/3.6 mo (95%CI: 2.7, 4.7/2.7, 5.9), 6-month survival 41%/38% (95% CI: 11%, 71%/2%, 75%). Conclusion: GBC and GBE are active in advanced PC. Toxicity, principally related to B, is moderate. The trial proceeds to a 2nd stage if 1 more response is observed in each arm. Supported by NCI grant N01-CM-17102.

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A phase II study of the safety and efficacy of the MDR inhibitor VX-710 combined with doxorubicin and vincristine in small cell lung cancer

17001

Background: Tumors with multidrug resistance (MDR) frequently show upregulation of efflux proteins MDR protein (MRP-1) and P-glycoprotein (Pgp). MDR represents a major obstacle to successful chemotherapy treatment and can be reversed in Pgp or MRP1-expressing cells by the MDR inhibitor VX-710. A phase II study was designed to evaluate the safety/tolerability and efficacy of VX-710 combined with doxorubicin (D) and vincristine (V) in patients (pts) with relapsed SCLC. Methods: Eligible pts had progressive, measurable disease and a PS <2 after response to 1st-line chemotherapy. Stage I safety evaluation was done with planned expansion to a second stage if 9 responses were confirmed in the first 35 pts. Pts were treated with VX-710 (120 mg/m2/h) for 72 hours with D (45 mg/m2) and V (1.4 mg/m2) given 4 hours after the start of VX-710. Pts were treated q 21 days until progression or intolerable adverse events (AEs). Severe neutropenia was noted in the first 15 pts, so the protocol was amended to include prophylactic G-CSF or ciprofloxacin. Interim analysis was performed after 36 pts were treated. Results: 36 pts were enrolled from 12/98 to 12/00. Neutropenia was the major toxicity, occurring in 25/36 (69%) pts. This was more severe (30% vs. 20% grade 4) and occurred earlier (58% vs. 38% in cycle 1) among the 15 pts enrolled prior to an amendment requiring neutropenia prophylaxis vs. those enrolled afterward. Other common treatment-related AE’s: asthenia (53%), nausea (50%), constipation (44%), alopecia (42%), dyspnea (42%), anemia (42%). 67% were grade 1 or 2 in severity. Four pts died on study or within 30 days of termination: 2 from infections likely related to therapy and 2 from disease progression. Among 32 evaluable pts, 7 (22%) had partial responses; 6 of these sustained responses through 6 cycles (with one response lasting 3 years). Three additional pts had unconfirmed responses. Median survival was 6 months (95% CI 4–7 months). Conclusions: The addition of VX-710 to D and V therapy did not improve anti-tumor activity or survival. Hematologic toxicity was severe, causing 2 pt deaths from neutopenic fever. Although there were some durable responses, response criteria were not met to proceed with stage 2. Further development with VX-710 has since stopped.

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A phase II trial of oblimersen sodium (G3139) in combination with doxorubicin (DOX) in advanced hepatocellular carcinoma (HCC). NCI protocol # 5798

14072

Background: Advanced HCC is refractory to most standard forms of chemotherapy, however responses to DOX are seen. The bcl-2 protein confers resistance to apoptosis in cancer cells and is important in tumor progression and resistance to chemotherapy. The bcl-2 antisense oligonucleotide, G3139 (G), has been shown to enhance the activity of DOX in tumor models by blocking bcl-2 synthesis. This argues for evaluating G + DOX in combination in HCC. By decreasing tumor bcl-2 protein levels, HCC may be sensitized to the apoptotic effects of DOX. Methods: We completed a phase II trial evaluating treatment with G at 7 mg/ kg for 7 days cont. i.v. infusion (d1–8) plus DOX at 45 mg/m2 i.v. bolus d5, every 28 d (as determined from our phase I HCC study). Eligible patients (pts) had path-confirmed, measurable, advanced HCC. Minimal eligibility included Childs-Pugh A cirrhosis, adequate hematological (hem) parameters and ECOG PS <2. Tumor biopsies for correlative studies were obtained at baseline and cycle 1 d 4 in consenting pts. Results: 19 patients were accrued, 1 was ineligible, 18 evaluable for toxicity, 17 evaluable for response; receiving a median (med) of 2 cycles (range 1,10). Risk for HCC was 39% HBV, 22% HCV, 17% alcohol, 22% other. Most common toxicities were hem and could be attributed to both G+DOX and to G alone. Overall grade 3–4 toxicities seen were: ANC- 67% (med nadir d 24–25), lymphopenia - 44%, thrombocytopenia - 6%, transaminitis - 33% and grade 1–2 G-fever - 67%. No responses were seen and the trial was stopped at stage 1. Six patients (35%) had stable disease, with one pt completing 10 cycles as per protocol (pt # 22). Med TTP is 1.8 months (1.7-NA) and 6-month PFS is 17.2% (5.3–56.4). 18 of 19 pts have died with med OS of only 5.4 months (2.7–11.6). Correlative studies on 3 available pts’ paired tumor biopsies showed absent baseline bcl-2 expression but moderate expression of both bcl-xl and BAX protein and with no change after exposure to G (includes pt #22). Conclusions: G + DOX is inactive in HCC at this dose and schedule. The overlap of hem toxicity may have resulted in suboptimal DOX dosing in HCC. Low baseline bcl-2 tumor expression relative to bcl-xl seen may suggest a relative insensitivity to the effects of bcl-2 inhibition in these HCC tumors.

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Gene expression patterns identify patients with non-small cell lung cancer (NSCLC) who are at increased risk for venous thromboembolism (VTE)

8535

Background: VTE is the leading cause of death in patients with cancer. The 1 year survival rate in patients diagnosed with cancer at time of VTE is 12% compared to 36% in cancer patients who are free of VTE .Also, a thrombotic event in a hospitalized cancer patient leads to higher in-hospital mortality.Thus,VTE in cancer patients may indicate a more aggressive phenotype. Methods: With the overarching goal of testing the ability of genomic profiling to detect biologically and clinically significant differences in patients with cancer and VTE, using NSCLC as a proof of principle, we expanded on previous work wherein we have shown the ability of multiple gene expression patterns (‘metagenes’) to predict a thrombotic event .96 patients with NSCLC were enrolled in this study. RNA was extracted and gene array data obtained using an Affymetrix U133 2.0 plus GeneChip. The clinical history of all 96 patients was reviewed to identify patients with a definitive VTE episode after the initial diagnosis of cancer and not within six weeks of surgery.14/96 (14.5%) patients met these criteria. We then identified 14 additional patients with NSCLC matched by age, gender and clinical stage patients who did not have VTE for at least 2 years following the diagnosis of cancer. Gene expression data was analyzed using a binary regression analysis. Results: Using the metagene approach, a discriminator gene set (n = 45) that differentiated patients with NSCLC and VTE from patients with NSCLC without VTE was identified. A leave-one-out cross validation performed to further assess the reliability of the discriminator metagene set was more than 85% accurate in identifying patients with NSCLC and VTE. Also, significant biologically relevant differences were seen between the comparison groups, to include genes such as P53, VEGFC, E2F4, TFPI and EPHB2 Conclusions: Our data suggests that a genomic approach can be used to identify with NSCLC that develop VTE, while also providing information important to an understanding of the underlying biology of the association between cancer and thrombosis. We are in the process of validating these results in a prospective trial.

No significant financial relationships to disclose.

Results of an interim analysis of a multinational randomized, double-blind, phase III study in patients (pts) with previously treated metastatic colorectal cancer (mCRC) receiving FOLFOX4 and PTK787/ZK 222584 (PTK/ZK) or placebo (CONFIRM 2)

3508

Background: PTK/ZK is a novel, oral, small molecule, antiangiogenic compound that inhibits tyrosine kinase signaling of all known vascular endothelial growth factor (VEGF) receptors. Methods: 855 pts were randomized to FOLFOX4 plus PTK/ZK (1250 mg, qd), or placebo. Eligibility included histologically or cytologically documented mCRC, pretreatment for metastatic disease with irinotecan/fluoropyrimidine-based chemotherapy, measurable disease by RECIST, PS of 0–2 and adequate organ and bone marrow function. The primary endpoint is overall survival (OS). Secondary endpoints included OS and PFS in high LDH pts (stratifiedbybaseline serum LDH levels > 1.5 × ULN). Results: OS was 12.1 mo in the PTK/ZK arm and 11.8 mo in the placebo arm (HR: 0.94; p=0.511). A pre-planned triangular test suggested a low probability of demonstrating an improvement in OS at the final analysis (4Q 2006). The response rates (CR+PR) were 18.5% in the PTK/ZK arm, 17.5% in the placebo arm. PFS was significantly longer in the PTK/ZK arm (5.5 mo vs. 4.1 mo; HR: 0.83; p=0.026). LDH, usually a poor prognostic factor in mCRC, is predictive of the outcome in the PTK/ZK arm. Pts with high LDH showed a strong improvement in PFS when treated with PTK/ZK (5.6 mo vs. 3.8 mo; HR: 0.63; p<0.001) and an improved OS (9.6 mo vs. 7.5 mo; HR: 0.78; p=0.10). Adverse events (AE) were similar to that of the CONFIRM 1 trial (ASCO 2005). Most frequent grade 3/4 AE associated with PTK/ZK were hypertension (PTK/ZK: 21%; placebo: 5%), diarrhea (16%; 8%), fatigue (14.5%; 6.9%), nausea (11%; 5%), vomiting (9%; 5%), dizziness (9%; 1%). AEs were generally reversible. Thrombotic and embolic events of all grades occurred in 6% (PTK/ZK) vs. 1% (placebo) and 4% vs. 1%, respectively. There was no increase in bowel perforations, hematological toxicities or peripheral neuropathy in the PTK/ZK arm. Conclusions: While the primary endpoint for OS was not met, PTK/ZK improves PFS significantly in the overall population, and shows strong activity in patients with high baseline serum LDH.

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Organ doses from prostate radiotherapy and associated concomitant exposures

In addition to the therapeutic exposure, a course of radiotherapy will involve the additional (concomitant) irradiation of the patient using CT, simulator or portal imaging systems, for localization of the target volume and subsequent verification of treatment delivery. The number of concomitant exposures is likely to increase as the developing technical capabilities for conformal, image-guided radiotherapy make target and critical organ definition an increasingly important aspect of radiotherapy. Estimation of doses and risks to critical organs in the body from all sources is thus necessary to provide the basis for adequate justification of the exposures as required by ICRP. In this paper, doses to selected organs and tissues for which ICRP have identified fatal cancer probabilities have been measured using a realistic anthropomorphic phantom loaded with thermoluminescent dosemeters and irradiated using a treatment protocol for radical radiotherapy of the prostate. Independently, doses to the same organs and tissues have been measured from concomitant CT and portal imaging exposures given for localization and verification purposes. Although negligible in comparison with the target dose, realistic numbers of concomitant exposures give a small but significant contribution to the total dose to most organs and tissues outside the target volume. Generally, this is in the range 5-10% of the total organ dose, but can be as high as 20% for bone surfaces. These data may be used to estimate concomitant doses from any combination of CT and portal imaging and may help in the justification process, especially when additional verification exposures may be required during treatment.

Particle number emissions and source signatures of an industrial facility

The work presented was conducted within the scope of a larger study investigating impacts of the Stuart Oil Shale project, a facility operating to the north of the industrial city of Gladstone, Australia. The aims of the investigations were threefold: (a) the identification of the plant signatures in terms of particle size distributions in the submicrometer range (13-830 nm) through stack measurements, (b) exploring the applicability of these signatures in tracing the source contributions at locations of interest, at a distance from the plant, and (c) assessing the contribution of the plant to the total particle number concentration at locations of interest. The stack measurements conducted for three different conditions of plant operation showed that the particle size distributions were bimodal with average modal count median diameters (CMDs) of 24 (SD 4) and 52 (SD 9) nm. The average of all the particle size distributions recorded within the plant sector at a site located 4.5 km from the plant, over the sampling period when the plant was operating, also showed a bimodal distribution. The modal CMDs in this case were 27 and 50 nm, similar to those at the stack. This bimodal size distribution is distinct from the size distribution of the most common ambient anthropogenic emission source, which is vehicle emissions, and can be considered as a signature of this source. The average contribution of the plant (for plant sector winds) was estimated to be (10.0 +/- 3.8) x 10(2) particles cm(-3) and constituted approximately a 50% increase overthe local particle ambient concentration for plant sector winds. This increase in particle number concentration compared to the local background concentration, while high compared to the clean environment concentration, is not significant when compared to concentrations generally encountered in the urban environment of Brisbane.