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Whistler, Canada

Davis A.,Australian National University | Tinker A.V.,Vancouver Center | Friedlander M.,University of New South Wales
Gynecologic Oncology | Year: 2014

"Platinum resistant" ovarian cancer was historically defined as disease recurrence within 6 months of completion of first-line platinum-based chemotherapy, although this is now more broadly applied to also include patients progressing within 6 months after multiple lines of chemotherapy. However, this definition ignores the heterogeneity and complexity of the spectrum of diseases that comprise "platinum resistant ovarian cancer" (PROC) and is innately flawed as it was initially derived using methods of detection of recurrence that would now be regarded as outdated. The outcome of patients with PROC is generally poor, with low response rates to further chemotherapy and a median survival of less than 12 months, but this is unpredictable and can be quite variable from study to study. This review outlines the complexity of PROC, examines how this impacts on the interpretation of the results of clinical trials, and explores how the definition may be improved. We also briefly describe the mechanisms of platinum resistance, the results of clinical trials to date as well as treatment options for patients with PROC and highlight the need for better methods of assessing clinical benefit in this poor prognostic sub group of patients. Crown Copyright © 2014 Published by Elsevier Inc. All rights reserved.

AlDuhaiby E.Z.,University of Toronto | Breen S.,University of Toronto | Bissonnette J.-P.,University of Toronto | Sharpe M.,University of Toronto | And 4 more authors.
Radiation Oncology | Year: 2012

Background: The timely and appropriate adoption of new radiation therapy (RT) technologies is a challenge both in terms of providing of optimal patient care and managing health care resources. Relatively little is known regarding the rate at which new RT technologies are adopted in different jurisdictions, and the barriers to implementation of these technologies.Methods: Surveys were sent to all radiation oncology department heads in Canada regarding the availability of RT equipment from 2006 to 2010. Data were collected concerning the availability and use of Intensity Modulated Radiation Therapy (IMRT) and stereotactic radiosurgery (SRS), and the obstacles to implementation of these technologies.Results: IMRT was available in 37% of responding centers in 2006, increasing to 87% in 2010. In 2010, 72% of centers reported that IMRT was available for all patients who might benefit, and 37% indicated that they used IMRT for "virtually all" head and neck patients. SRS availability increased from 26% in 2006 to 42.5% in 2010. Eighty-two percent of centers reported that patients had access to SRS either directly or by referral. The main barriers for IMRT implementation included the need to train or hire treatment planning staff, whereas barriers to SRS implementation mostly included the need to purchase and/or upgrade existing planning software and equipment.Conclusions: The survey showed a growing adoption of IMRT and SRS in Canada, although the latter was available in less than half of responding centers. Barriers to implementation differed for IMRT compared to SRS. Enhancing human resources is an important consideration in the implementation of new RT technologies, due to the multidisciplinary nature of the planning and treatment process. © 2012 AlDuhaiby et al; licensee BioMed Central Ltd.

Chapman J.-A.W.,Queens University | Nielsen T.O.,University of British Columbia | Ellis M.J.,University of Washington | Bernard P.,University of Utah | And 8 more authors.
Breast Cancer Research | Year: 2013

Introduction: We hypothesized improved inter-laboratory comparability of estrogen receptor (ER) and progesterone receptor (PgR) across different assay methodologies with adjunctive statistical standardization, akin to bone mineral density (BMD) z-scores. We examined statistical standardization in MA.12, a placebo-controlled pre-menopausal trial of adjuvant tamoxifen with locally assessed hormone receptor +/- tumours, and in a cohort of post-menopausal British Columbia (BC) tamoxifen-treated patients. Methods: ER and PgR were centrally assessed for both patient groups with real time quantitative reverse transcription polymerase chain reaction (qPCR) and immunohistochemistry (IHC). Effects on disease-free survival (DFS) were investigated separately for 345 MA.12 and 673 BC patients who had both qPCR and IHC assessments. Comparisons utilized continuous laboratory units and statistically standardized z-scores. Univariate categorization of ER/PgR was by number of standard deviations (SD) above or below the mean (z-score ≥1.0 SD below mean; z-score <1.0 SD below mean; z-score ≤1.0 SD above mean; z-score >1.0 SD above mean). Exploratory multivariate examinations utilized step-wise Cox regression. Results: Median follow-up for MA.12 was 9.7 years; for BC patients, 11.8 years. For MA.12, 101 of 345 (29%) patients were IHC ER-PgR-ER was not univariately associated with DFS (qPCR, P = 0.19; IHC, P = 0.08), while PgR was (qPCR, P = 0.09; IHC, P = 0.04). For BC patients, neither receptor was univariately associated with DFS: for ER, PCR, P = 0.36, IHC, P = 0.24; while for PgR, qPCR, P = 0.17, IHC, P = 0.31. Multivariately, MA.12 patients randomized to tamoxifen had significantly better DFS (P = 0.002 to 0.005) than placebo. Meanwhile, jointly ER and PgR were not associated with DFS whether assessed by qPCR or by IHC in all patients, or in the subgroup of patients with IHC positive stain, for pooled or separate treatment arms. Different results by type of continuous unit supported the concept of ER level being relevant for medical decision-making. For postmenopausal BC tamoxifen patients, higher qPCR PgR was weakly associated with better DFS (P = 0.06). Conclusions: MA.12 pre-menopausal patients in a placebo-controlled tamoxifen trial had similar multivariate prognostic effects with statistically standardized hormone receptors when tumours were assayed by qPCR or IHC, for hormone receptor +/- and + tumours. The BC post-menopausal tamoxifen cohort did not exhibit a significant prognostic association of ER or PgR with DFS. Adjunctive statistical standardization is currently under investigation in other NCIC CTG endocrine trials. © 2013 Chapman et al.; licensee BioMed Central Ltd.

Lengoc S.,British Columbia Cancer Agency BCCA | Soo J.,British Columbia Cancer Agency BCCA | McGahan C.E.,Vancouver Center | French J.,British Columbia Cancer Agency BCCA | And 3 more authors.
Journal of Medical Imaging and Radiation Sciences | Year: 2012

Background: Previous studies have shown that palliative radiation therapy (PRT) is often underused, especially in rural and remote settings despite evidence supporting its effectiveness in managing symptoms from advanced or metastatic cancer. Purpose: To identify factors which influence family physicians (FPs) in British Columbia (BC) to refer patients for PRT at the BC Cancer Agency (BCCA) and to compare referral patterns between FPs in rural and urban areas. Methods and Materials: A total of 1,001 questionnaires were sent to all FPs practicing in rural areas and randomly to FPs in urban areas (351 and 650, respectively). Rural and urban areas were chosen based on our previous study of utilization rates of PRT in BC. The questionnaire was adapted from a previously validated survey, and was used to obtain information on referral practices of FPs in BC. FPs who did not practice family medicine or where 80% of their practice was spent with either obstetrical or pediatric patients were excluded. Results: The overall response rate was 33% (44% rural vs. 28% urban). Rural FPs were more involved in both palliative care and metastatic cancer management of their patients (88% vs. 74%; P = .01 and 58% vs. 39%; P = .01). No difference was observed in the FPs' awareness of the BCCA's Radiation Oncology Program. The most significant factors influencing an FP to refer a patient for PRT were: poor functional status, inconvenience to travel and life expectancy. A higher proportion of rural FPs had 10 years or less of experience in family practice than the urban FPs (P = .03). There was no significant difference in the formal training or additional training between the rural and urban FPs. Conclusions: This study found that FPs practicing in rural areas were more involved in palliative management of their patients and participated more in the care of patients with advanced or metastatic cancer than those in urban areas. They also more commonly referred patients for palliative radiotherapy than their urban counterparts. The reported factors that influenced rural and urban FPs to refer were patients' functional status and life expectancy, combined with uncertain benefit and potential side effects of radiotherapy. More than twice as many FPs from rural compared to urban areas were influenced by perceived inconvenience to travel for palliative radiotherapy. After controlling for potential confounding factors, FP awareness of the radiotherapy program, high participation in advanced, metastatic, or palliative care of cancer patients, formal training in radiation oncology, and additional training in palliative care were all associated with an increased probability of ever referring for palliative radiotherapy. © 2012 Elsevier Inc.

Kwan W.,BC Cancer Agency | Duncan G.,BC Cancer Agency | Duncan G.,Vancouver Center | Van Patten C.,BC Cancer Agency | And 4 more authors.
Nutrition and Cancer | Year: 2010

Our objective was to evaluate the tolerability and effect of a daily soy beverage in prostate cancer patients with biochemical failure after radiotherapy. Patients with rising prostate-specific antigen (PSA) after radical radiation for prostate cancer were instructed to consume 500 ml of soy beverage daily for 6 mo. Tolerability of the soy beverage and compliance were assessed. PSA doubling times before and after the consumption of soy were compared. Thirty-four subjects were enrolled; 5 withdrew before 1 mo of soy for reasons unrelated to soy consumption. All remaining 29 subjects were included in the analysis. Mean consumption of the assigned soy beverage was 93%. Mild gastrointestinal upset (38%) not affecting soy consumption was the commonest side effect. PSA showed a declining trend in 4 patients (13.8%), and there was a >100% prolongation of PSA doubling time in 8 patients (27.6%). However, PSA doubling time also showed a 50% or more shortening in 5 patients (17.2%). In our cohort of North American subjects, 6 mo of a daily soy beverage was well tolerated and was associated with a declining trend or more than 2 times prolongation of PSA doubling time in 41% of subjects. Confirmatory studies are warranted.

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