A cost-outcome analysis of adjuvant postmastectomy locoregional radiotherapy in premenopausal node-positive breast cancer patients.

Purpose: To calculate cost-effectiveness and cost-utility ratios for adjuvant postmastectomy locoregional radiotherapy in premenopausal node-positive breast cancer patients and to place these ratios in the context of generally accepted medical expenditures.

Materials And Methods: A spreadsheet-based activity costing model using 1997 Canadian (cdn) capital, operating, and administrative costs has been used to identify, from the institutional perspective, the incremental cost of adding radiotherapy to surgery and chemotherapy for this group of patients. Outcome data were derived from two recently published clinical trials and were converted to discounted incremental life years and quality-adjusted life years gained.

Prostate cancer risk. Medical history, sexual, and hormonal factors.

PURPOSE: Various medical conditions, infectious agents, sexual, and hormonal factors have been investigated in relation to prostate cancer risk. Given inconsistent results these factors were examined in this study.METHODS: This population-based case-control study was conducted in northeastern Ontario from 1995 to 1999.

Regulation of protein kinase C by the cytoskeletal protein calponin.

Previous studies from this laboratory have shown that, upon agonist activation, calponin co-immunoprecipitates and co-localizes with protein kinase Cepsilon (PKCepsilon) in vascular smooth muscle cells. In the present study we demonstrate that calponin binds directly to the regulatory domain of PKC both in overlay assays and, under native conditions, by sedimentation with lipid vesicles. Calponin was found to bind to the C2 region of both PKCepsilon and PKCalpha with possible involvement of C1B.

Role of specific apoptotic pathways in the restoration of paclitaxel-induced apoptosis by valspodar in doxorubicin-resistant MCF-7 breast cancer cells.

Paclitaxel (Taxol) kills tumor cells by inducing both cellular necrosis and apoptosis. A major impediment to paclitaxel cytotoxicity is the establishment of multidrug resistance whereby exposure to one chemotherapeutic agent results in cross-resistance to a wide variety of other drugs. For example, selection of MCF-7 breast cancer cells for resistance to doxorubicin (MCF-7ADR cells) results in cross-resistance to paclitaxel.

An economic framework for evaluating a multileaf collimator.

Objectives: As health care budgets continue to face close scrutiny, any new acquisition must be evaluated for both costs and outcomes. This study was undertaken to demonstrate the application of an economic framework for the evaluation of a multileaf collimator as an example of a new technology that can have both quantifiable and nonquantifiable benefits for patients, staff, and cancer care institutions.

Methods: Using financial data from the Northeastern Ontario Regional Cancer Centre (NEORCC) and a recognized staffing model, a commercial spreadsheet, developed to economically characterize the principal radiotherapy processes has been used to determine the net incremental annual cost of a multileaf collimator (MLC).

Impact of noninvasive imaging on increased incidental detection of renal cell carcinoma.

Objective: To determine the impact of non-invasive imaging, specifically ultrasound imaging and computed tomography, on the incidental detection of renal cell carcinoma during two consecutive time periods, one prior and one subsequent to the acquisition of imaging equipment.

Methods: All located patient charts (83% of 207) of renal cell carcinoma cases (n = 172) were reviewed, and categorized by presentation method as 'incidental' or 'nonincidental' cases, based on defined criteria. Clinical information was recorded, cases were staged, and survival estimates were calculated.

Descriptive study to compare patient recall of information: nurse-taught versus video supplement.

An important goal in oncology nursing is to provide outpatients receiving chemotherapy with adequate information about their treatment so they will be able to cope with treatment reactions and make appropriate decisions about seeking early medical attention when potentially serious side-effects occur. The purpose of the present study was to evaluate patient teaching strategies at one cancer centre. A comparative descriptive study design was employed.

The cost of radiotherapy as a function of facility size and hours of operation.

Against a background of constant or decreasing budgets, this study was undertaken to investigate the economic effects of changes in selected operational parameters within a radiation treatment programme. Using financial data from the Northeastern Ontario Regional Cancer Centre and a recognized staffing model, a commercial spreadsheet has been used to calculate the cost of an 18 fraction course of radiotherapy, including all the major preparatory processes such as simulation and treatment planning. Using the spreadsheet, and on the basis of explicit and reasonable assumptions, the cost of radiotherapy has been calculated as the facility size (i.

The mode of action of taxol: apoptosis at low concentration and necrosis at high concentration.

The cytotoxicity of Taxol represents both inhibition of cell proliferation and cell death. The drug blocked cells in the G2/M phase of the cell cycle. It has also been reported that Taxol induced cell apoptosis; however, the mode of action of Taxol is far from clear.

Computer-assisted decision making in portal verification--optimization of the neural network approach.

Purpose: Conventional portal verification requires that a qualified radiation oncologist make decisions as to the set-up acceptability. This scheme is no longer sustainable with the large numbers of images available on-line and stringent time constraints. Therefore the objective of this study was to develop, optimize, and evaluate on clinical data an artificial intelligence decision-making tool for portal verification.

Expression of C-erbB-2/HER-2 in patients with metastatic breast cancer undergoing high-dose chemotherapy and autologous blood stem cell support.

C-erbB-2/HER-2 (designated HER-2) is overexpressed in both primary and metastatic breast cancer and predicts poor prognosis. We investigated the expression of HER-2 in patients with metastatic breast cancer undergoing high-dose chemotherapy (HDCT) with autologous blood stem cell (ABSC) support and correlated the presence (positive) or absence (negative) of HER-2 overexpression in these patients with response to treatment, progression-free survival (PFS) and overall survival (OS). The level of HER-2 expression was analyzed in 57 patients with metastatic breast cancer undergoing HDCT with ABSC support.

Lack of modulation of MDR1 gene expression by dominant inhibition of cAMP-dependent protein kinase in doxorubicin-resistant MCF-7 breast cancer cells.

The drug transporter P-glycoprotein (P-gp) appears to play an important role in the ability of tumor cells to evade killing by chemotherapeutic agents. Using pharmacological inhibitors of cAMP-dependent protein kinase (PKA), it has been suggested that, similar to rodent model systems, the human P-gp gene (MDR1) is also under PKA-dependent control and that PKA inhibition may prove useful in reducing drug resistance in human cancer cells. To test this hypothesis, we stably transformed doxorubicin (Adriamycin)-resistant human MCF-7 breast cancer cells (MCF-7(ADR)) with a vector that inhibits PKA activity by inducing over-expression of mutant type Ialpha PKA regulatory (RIalpha) subunits.

The tumor suppressor p53 can reduce stable transfection in the presence of irradiation.

The tumor suppressor p53 is believed to play an essential role in maintaining genome stability. Although it is currently unknown how p53 is involved in this important biological safeguard, several previous publications indicate that p53 can help to maintain genome integrity through the recombination-mediated DNA repair process. The integration of linearized plasmid DNA into the host chromosome utilizes the same repair process, and the frequency can be measured by clonogenic assays in which cells that were stably transfected by plasmid integration can be scored by their colony-forming abilities.

Endocytosis deficiency of epidermal growth factor (EGF) receptor-ErbB2 heterodimers in response to EGF stimulation.

Epidermal growth factor (EGF) stimulates the homodimerization of EGF receptor (EGFR) and the heterodimerization of EGFR and ErbB2. The EGFR homodimers are quickly endocytosed after EGF stimulation as a means of down-regulation. However, the results from experiments on the ability of ErbB2 to undergo ligand-induced endocytosis are very controversial.

Psychological distress associated with organized breast cancer screening.

Regular breast cancer screening with the use of mammography for asymptomatic women is the most effective method for the early detection of breast cancer. Although the health and economic implications of breast cancer screening have received a great deal of attention, the psychological consequences of attending a breast screening program that includes mammography have been largely ignored. This article briefly reviews 10 studies that have examined the psychological distress associated with organized breast cancer screening.

A test tool for the visual verification of light and radiation fields using film or an electronic portal imaging device.

We describe the design and evaluation of a simple test tool which can be used in conjunction with either film or an electronic portal imaging device (EPID) to verify light and radiation fields and their congruence. The precision of the technique is better than 0.5 mm under all conditions tested.

Application of a fuzzy pattern classifier to decision making in portal verification of radiotherapy.

With the large volume of electronic portal images acquired and stringent time constraints, it is no longer feasible to follow the convention whereby the radiation oncologist reviews and approves or rejects all portals. For that purpose we have developed a portal image classifier based on the fuzzy k-nearest neighbour (k-NN) algorithm. Each portal image is represented by a feature vector that consists of translational and rotational errors in the placement of radiation field borders that were measured in the portal image.

Carbon source-dependent regulation of cell growth by murine protein kinase C epsilon expression in Saccharomyces cerevisiae.

Protein kinase C is known to play a role in cell cycle regulation in both lower and higher eucaryotic cells. Since mutations in yeast proteins involved in cell cycle regulation can often be rescued by the mammalian homolog and since significant conservation exists between PKC-signalling pathways in yeast and mammalian cells, cell cycle regulation by mammalian PKC isoforms may be effectively studied in a simpler genetically-accessible model system such as Saccharomyces cerevisiae. With this objective in mind, we transfected S.

A phase I trial of high-dose paclitaxel, cyclophosphamide and mitoxantrone with autologous blood stem cell support for the treatment of metastatic breast cancer.

The aim of this phase I study was to determine the dose limiting toxicity (DLT), maximum tolerated dose (MTD) and efficacy of a new combination of cyclophosphamide (6 g/m2), mitoxantrone (70 mg/m2), with dose escalation of paclitaxel (TaxolR) at a starting dose of 250 mg/m2 given intravenously over 3 h in a transplantation setting. Patients with metastatic breast cancer and chemosensitive disease were eligible. The autologous blood stem cell re-infusion and subsequent recovery occurred in an out-patient setting.

Oncology nursing research priorities: a Canadian perspective.

The purpose of the study was to determine oncology nursing research priorities among Canadian oncology nurses. The following two groups of nurses were mailed survey questionnaires: oncology nurse researchers and nurses working in oncology clinical settings who were members of the Canadian Association of Nurses in Oncology (CANO). The questionnaire was based on prior Oncology Nursing Society (ONS) research surveys and the oncology nursing literature.

A potential moderating role of stress in the association of disease activity and psychological status among patients with rheumatoid arthritis.

This study investigated the role of perceived daily stress as a potential moderator in the relation between a set of predictors (disease activity, education, pain) and psychological status (anxiety, depression) of 31 patients with rheumatoid arthritis. Psychological measures served as dependent variables in hierarchical regression analyses testing for potential interaction effects of daily stress upon relationships between predictors and dependent measures. No predictors predicted directly scores on depression and anxiety; however, daily stress directly predicted scores on depression and anxiety, even after having separately controlled for each of the predictors.

Computer-aided radiation therapy simulation: image intensifier spatial distortion correction for large field of view digital fluoroscopy.

An accurate method of correcting spatial distortion in digital fluoroscopy images has been developed for generating fluoroscopy-based large field of view images for computer-aided radiation therapy simulation. This method is applicable to arbitrary gantry rotations and arbitrary shifts of the image intensifier relative to the central axis of the x-ray beam. It is therefore suitable for conventional radiation therapy simulation techniques that involve the arbitrary positioning of the image intensifier by the operator.

An image registration scheme applied to verification of radiation therapy.

The introduction of modern conformal radiation therapy techniques requires high geometric precision in treatment delivery which must be verified. For that purpose we have developed an automated system based on registration of portal and simulation (or planning) image pairs. The image registration is performed on anatomical features which are automatically extracted from the portal image.

Integrins and matrix molecules in salivary gland cell adhesion, signaling, and gene expression.

Integrins play crucial roles in embryonic and adult cell adhesion, migration, morphogenesis, growth, and differentiation in many cell systems, including human salivary gland cells. Integrins function by binding through their extracellular domain to a specific peptide recognition site in a ligand, and then transmitting information to the cytoplasm by way of their cytoplasmic tails. By this transmembrane signaling process, integrins can mediate assembly of adhesion sites and organization of the actin-containing cytoskeleton by forming supermolecular complexes of cytoskeletal and signaling molecules.

Decrease in tumor cell contamination and progenitor cell yield in leukapheresis products after consecutive cycles of chemotherapy for breast cancer treatment.

In this retrospective study, we assessed the impact of each of three consecutive cycles of conventional-dose chemotherapy on CD34+ cells, colony-forming units granulocyte-macrophage (CFU-GM), and contaminating breast cancer cells collected in the leukapheresis products of patients with metastatic breast cancer. The patients subsequently underwent high-dose chemotherapy followed by autologous blood progenitor cell transplantation. We analyzed 172 leukapheresis products from 17 patients and have correlated the long-term clinical outcome with tumor cell contamination.