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Clinical Lung Cancer | 2014

Third-Line Chemotherapy in Small-Cell Lung Cancer: An International Analysis

Demetrios Simos; Golmehr Sajjady; Melissa Sergi; Mun Sem Liew; Raffaele Califano; Cheryl Ho; N. Leighl; Shane C White; Yvonne Summers; William Petrcich; Paul Wheatley-Price

INTRODUCTION Small-cell lung cancer is an aggressive disease for which the mainstay of treatment is chemotherapy. Despite good initial responses most patients will relapse. Some will receive second-line therapy with clinical benefit, but for third-line chemotherapy there is little evidence to guide treatment decisions and the benefits of treatment are unknown. This study investigated the treatment of SCLC in the third-line setting. PATIENTS AND METHODS An international, multicenter retrospective analysis of patients who received at least 3 lines of chemotherapy for their SCLC was performed. RESULTS From 2000 to 2010, 120 patients were identified from 5 centers: median age 61, 40% (n = 72) limited stage, and 79% (n = 95) Eastern Cooperative Oncology Group performance status of 0 to 1. Only 22% of these patients received 3 distinct lines of chemotherapy. The remainder were rechallenged with a chemotherapy regimen used at least once previously. Six percent received platinum-based chemotherapy in all 3 lines. In third-line, response rate was 18% and median overall survival was 4.7 months. Factors associated with longer survival included normal baseline LDH levels and response to second-line chemotherapy. On multivariate analysis only normal baseline LDH retained statistical significance. Thirty-five patients went on to receive chemotherapy beyond the third line. CONCLUSION Few SCLC patients receive 3 chemotherapy lines. Most patients were rechallenged with a similar regimen at least once. Response and survival in the third-line setting are modest. Lack of response to second-line chemotherapy and elevated baseline LDH level might predict lack of benefit from third-line treatment. This data set does not include patients receiving fewer lines for comparison.


JAMA Oncology | 2015

Use of Preoperative Magnetic Resonance Imaging for Breast Cancer: A Canadian Population-Based Study.

Angel Arnaout; Christina Catley; Christopher M. Booth; Matthew D. F. McInnes; Ian D. Graham; Vikaash Kumar; Demetrios Simos; Carl van Walraven; Mark Clemons

IMPORTANCE Contrary to practice guidelines, breast magnetic resonance imaging (MRI) is commonly used in the preoperative evaluation of women with breast cancer. While existing literature has found little benefit to MRI in most patients, potential downstream consequences associated with breast MRI are not well described. OBJECTIVE To describe patterns of preoperative breast MRI utilization in a health care system with universal insurance and its association with downstream investigations and clinical outcomes. DESIGN, SETTING, AND PARTICIPANTS This was a population-based retrospective cohort study using administrative heath care databases in Ontario, Canada (2012 population, 13.5 million) over 14 geographic regions were evaluated within the data set. Participants comprised 53 015 patients with primary operable breast cancer treated from 2003 to 2012. MAIN OUTCOMES AND MEASURES Use of preoperative breast MRI by year, geographic region, and breast cancer stage. Postdiagnosis imaging, biopsy, and short-term surgical outcomes were also evaluated between those who did and did not receive MRI. RESULTS Overall, 14.8% of patients (7824 of 53 015) had a preoperative MRI. During the 10-year study period, MRI use increased across all stages by 8-fold (from 3% to 24%; P < .001 for trend). Factors associated with MRI use were younger age, higher socioeconomic status, higher Charlson comorbidity score, surgery performed in a teaching hospital, and fewer years of surgeon experience. Multivariate analyses showed that preoperative breast MRI was associated with higher likelihood of the following: postdiagnosis breast imaging (odds ratio [OR], 2.09; 95% CI, 1.92-2.28), postdiagnosis breast biopsies (OR, 1.74; 95% CI, 1.57-1.93), postdiagnosis imaging to assess for distant metastatic disease (OR, 1.51; 95% CI, 1.42-1.61), mastectomy (OR, 1.73; 95% CI, 1.62-1.85), contralateral prophylactic mastectomy (OR, 1.48; 95% CI, 1.23-1.77), and a greater than 30-day wait to surgery (OR, 2.52; 95% CI, 2.36-2.70) (all ORs are adjusted). CONCLUSIONS AND RELEVANCE Preoperative breast MRI use has increased substantially in routine clinical practice and is associated with a significant increase in ancillary investigations, wait time to surgery, mastectomies, and contralateral prophylactic mastectomies.


Journal of bone oncology | 2012

A national portfolio of bone oncology trials—The Canadian experience in 2012

Iryna Kuchuk; Demetrios Simos; Christina L. Addison; Mark Clemons

Background The impact of both cancer and its treatment on bone is an essential component of oncological practice. Bone oncology not only affects patients with both early stage and metastatic disease but also covers the entire spectrum of tumour types. We therefore decided to review and summarise bone oncology-related trials that are currently being conducted in Canada. Method We assessed ongoing and recently completed trials in Canada. We used available North American and Canadian cancer trial websites and also contacted known investigators in this field for their input. Results Twenty seven clinical trials were identified. Seven pertained to local treatment of bone metastasis from any solid tumour type. Seven were systemic treatment trials, five focused on bone biology and predictive factors, three evaluated safety of bone-targeted agents, three were adjuvant trials and two trials investigated impact of cancer therapy on bone health. The majority of trials were related to systemic treatment and bone biology in breast cancer. Most were small, single centre, grant-funded studies. Not surprisingly the larger safety and adjuvant studies were pharmaceutical company driven. Discussion Despite the widespread interest in bone-targeted therapies our survey would suggest that most studies are single centre and breast cancer focused. If major advances in bone oncology are to be made then collaborative strategies are needed to not only increase current sample sizes but to also expand these studies into non-breast cancer populations.


Canadian Medical Association Journal | 2015

Imaging for distant metastases in women with early-stage breast cancer: a population-based cohort study

Demetrios Simos; Christina Catley; Carl van Walraven; Angel Arnaout; Christopher M. Booth; Matthew D. F. McInnes; Dean Fergusson; Susan Dent; Mark Clemons

Background: Practice guidelines recommend that imaging to detect metastatic disease not be performed in the majority of patients with early-stage breast cancer who are asymptomatic. We aimed to determine whether practice patterns in Ontario conform with these recommendations. Methods: We used provincial registry data to identify a population-based cohort of Ontario women in whom early-stage, operable breast cancer was diagnosed between 2007 and 2012. We then determined whether imaging of the skeleton, thorax, and abdomen or pelvis had been performed within 3 months of tissue diagnosis. We calculated rates of confirmatory imaging of the same body site. Results: Of 26 547 patients with early-stage disease, 22 811 (85.9%) had at least one imaging test, and a total of 83 249 imaging tests were performed (mean of 3.7 imaging tests per patient imaged). Among patients with pathologic stage I and II disease, imaging was performed in 79.6% (10 921/13 724) and 92.7% (11 882/12 823) of cases, respectively. Of all imaging tests, 19 784 (23.8%) were classified as confirmatory investigations. Imaging was more likely for patients who were younger, had greater comorbidity, had tumours of higher grade or stage or had undergone preoperative breast ultrasonography, mastectomy or surgery in the community setting. Interpretation: Despite recommendations from multiple international guidelines, most Ontario women with early-stage breast cancer underwent imaging to detect distant metastases. Inappropriate imaging in asymptomatic patients with early-stage disease is costly and may lead to harm. The use of population datasets will allow investigators to evaluate whether or not strategies to implement practice guidelines lead to meaningful and sustained change in physician practice.


Expert Opinion on Pharmacotherapy | 2014

Pharmacotherapy of bone metastases in breast cancer patients – an update

Carmel Jacobs; Demetrios Simos; Christina L. Addison; Mohammed Fk Ibrahim; Mark Clemons

Introduction: Bone metastases in breast cancer patients are a common clinical problem and pose a threat to the quality of life of such patients. Multiple randomized trials have demonstrated the benefit of both bisphosphonates and denosumab in reducing the incidence and delaying the onset of skeletal related events (SREs) in breast cancer patients with bone metastases. Areas covered: We review the current literature on the use of bisphosphonates and denosumab along with strategies to maximize benefit and minimize risk of these agents. We also review potential future targets. Expert opinion: Despite the potent osteoclast inhibiting effects of the bone-targeted agents in current clinical use, we have likely maximized their ability to inhibit SREs and must in turn focus on minimizing their potential toxicity. The future will likely involve more novel treatment strategies as well as the development of new agents. The current ‘one size fits all’ approach for the management of breast cancer bone metastases will be replaced by ‘tailored’ treatment for each individual patient as we usher in the era of ‘personalized medicine.’ In addition, new bone-targeted agents (e.g., sclerostin inhibitors) and combinations will continue to be explored, as will the evaluation of the bone-targeting properties of more conventional non-osteoclast targeting therapies.


Current Opinion in Supportive and Palliative Care | 2014

Definition and consequences of locally advanced breast cancer.

Demetrios Simos; Mark Clemons; Ophira Ginsburg; Carmel Jacobs

Purpose of reviewLocally advanced breast cancer (LABC) represents the most advanced stage breast cancer that is still potentially curable with surgery, radiation, and systemic therapy. The purpose of this review is to discuss LABC in the context of modern practice with a focus on its definition and potential consequences. Recent findingsThere is no one encompassing definition for this disease, but in general cancers of the breast are considered to be locally advanced if they are large and/or have infiltrated into adjacent tissues (the overlying skin or underlying muscles) and/or are found to have extensive locoregional lymph node involvement. It is not surprising, therefore, that LABC can cause significant morbidity and mortality. SummaryRecent advances in our understanding of the biology of breast cancer have made it clear that LABC does not represent a single clinical entity but rather a heterogeneous group of breast tumors that share a common theme of extensive locoregional spread without overt evidence of distant metastatic disease. Despite advances in breast cancer screening and treatment LABC remains a significant global healthcare issue.


International Journal of Surgical Oncology | 2015

Evaluating the feasibility of performing window of opportunity trials in breast cancer.

Angel Arnaout; Susan Robertson; Iryna Kuchuk; Demetrios Simos; Gregory R. Pond; Christina L. Addison; Mehrzad Namazi; Mark Clemons

Background. The waiting period to surgery represents a valuable “window of opportunity” to evaluate novel therapeutic strategies. Interventional studies performed during this period require significant multidisciplinary collaboration to overcome logistical hurdles. We undertook a one-year prospective window of opportunity study to assess feasibility. Methods. Eligible newly diagnosed postmenopausal, estrogen receptor positive breast cancer patients awaiting primary surgery received anastrozole daily until surgery. Feasibility was assessed by (a) the proportion of patients who consented and (b) completed the study. Comparison of pre- and poststudy Ki67 labelling index and cleaved caspase 3 scores (CC3) was performed. Results. 22/131 (16.8%) patients were confirmed eligible and 20/22 (91%) patients completed the study. 19/20 (95%) patients agreed to undergo optional additional tissue biopsies. The mean duration of anastrozole use was 24.7 (15–44) days. There were a statistically significant decline in mean Ki67 indices of 48.8% (p < 0.001) and a trend towards significance in the decline of CC3 (p = 0.17) when comparing pre- with posttreatment values. Conclusion. window of opportunity trials in breast cancer are a feasible way of assessing the biologic efficacy of different therapies in the presurgical setting. The majority of eligible women were willing to participate including undergoing additional tissue biopsies.


Journal of Clinical Medicine | 2013

Bone-Targeted Agents for the Management of Breast Cancer Patients with Bone Metastases

Demetrios Simos; Christina L. Addison; Iryna Kuchuk; Brian Hutton; Sasha Mazzarello; Mark Clemons

Despite advances in adjuvant therapy for breast cancer, bone remains the most common site of recurrence. The goal of therapy for these patients is palliative and focused on maximizing the duration and quality of their life, while concurrently minimizing any disease or treatment-related complications. Bone metastases predispose patients to reduced survival, pain, impaired quality of life and the development of skeletal-related events. With an increased understanding of the pathophysiology of bone metastasis, effective treatments for their management have evolved and are now in widespread clinical use. This article will discuss the pathogenesis of bone metastases and review the key clinical evidence for the efficacy and safety of currently available systemic bone-targeted therapies in breast cancer patients with an emphasis on bisphosphonates and the receptor activator of nuclear factor kappa B ligand (RANKL) inhibitors. We will also discuss novel strategies and therapies currently in development.


Journal of bone oncology | 2016

A phase 2 trial exploring the clinical and correlative effects of combining doxycycline with bone-targeted therapy in patients with metastatic breast cancer

Christina L. Addison; Demetrios Simos; Z. Wang; Gregory R. Pond; S. Smith; S. Robertson; Sasha Mazzarello; Gurmit Singh; Lisa Vandermeer; Ricardo Fernandes; A. Iyengar; Shailendra Verma; Mark Clemons

Background Bone-targeting agents (BTAs), such as bisphosphonates and denosumab, have demonstrated no discernable effects on tumour response or disease free/overall survival in patients with bone metastases from breast cancer. Doxycycline is both osteotropic and has anti-cancer effects. When combined with zoledronate in animal models, doxycycline showed significantly increased inhibition of tumour burden and increased bone formation. We evaluated the effects of adding doxycycline to ongoing anti-cancer therapy in patients with metastatic breast cancer. Methods Breast cancer patients with bone metastases and ≥3 months of BTA use, entered this single-arm study. Patients received doxycycline 100 mg orally, twice a day for 12 weeks. The co-primary endpoints were; effect on validated pain scores (FACT-Bone pain and Brief Pain Inventory) and bone resorption markers (serum C-telopeptide, [sCTx]). All endpoints (pain scores, sCTx, bone-specific alkaline phosphatase, skeletal-related events, toxicity) were evaluated at baseline, 4, 8 and 12 weeks. Bone marrow was sampled at baseline and week 12 for exploratory biomarker analysis. Results Out of 37 enroled patients, 27 (73%) completed 12 weeks of therapy. No significant changes were seen in pain scores or bone turnover markers. Failure to complete treatment: drug toxicity (70%) and disease progression (30%). Sixteen (43%) patients had GI adverse events. Conclusions Doxycycline 100 mg twice daily for 12 weeks had no significant effects on either bone pain or bone turnover markers. Its toxicity profile in this patient population would make further evaluation challenging.


Journal of Clinical Oncology | 2014

A randomized, double-blind trial evaluating the palliative benefit of either continuing pamidronate or switching to zoledronate in patients with high-risk bone metastases from breast cancer (The Odyssey Study).

Carmel Jacobs; Iryna Kuchuk; Stephanie Smith; Sasha Mazzarello; Lisa Vandermeer; Nathan Bouganim; Susan Dent; S. Gertler; Shailendra Verma; Vince Young; Xinni Song; Demetrios Simos; George Dranitsaris; David Cella; Mark Clemons

155 Background: Questions remain around the optimal use of bone-targeted agents (BTA) in patients with bone metastases (BM) from breast cancer (BC). In Canada pamidronate (PAM) is the most commonly used BTA in BC.We explored whether a switch to a more potent BTA, like zoledronic acid (ZA), in patients who remain at high risk of skeletal related events (SREs) despite PAM use is associated with significant palliative benefit. METHODS BC patients with high risk BM (prior SRE, bone progression, bone pain or levels of bone turnover marker serum C-telopeptide (sCTX) >400ng/L) despite >3 months of PAM use were eligible. Patients were randomized in a double-blind manner to either switch to ZA or continue on PAM every 4 weeks for 12 weeks. Primary outcome was the proportion of patients achieving a fall in sCTX at 12 weeks. Secondary outcomes were pain control (BPI and FACT-BP) and toxicity. Results 73 patients completed the study. Median age 61 years (range 37 - 87), prior duration of PAM use 10 months (range 3 - 118). sCTX levels for all patients at baseline, 372+/- 471, week 12, 209 +/-290. Proportion of patients achieving a fall in sCTX from week 0 to week 12, 26/31 (84%) in ZA arm, 17/30 (57%) in PA arm, p=0.0262. Two patients were unable to complete the study due to deterioration in renal function (both receiving PAM), four due to progressive disease (two receiving ZA, two PAM), two patients chose to discontinue the study before completion (both receiving ZA). Four patients (5%) had SREs during the study, two receiving ZA, two receiving PAM. Quality of life and pain analysis shows no difference between week 0 and week 12 scores in either arm. Toxicity was predominantly grade 1 and 2, numerically there were more adverse effects in the ZA arm than PAM. Conclusion Switching patients with high risk BM from PAM to ZA leads to a reduction in sCTX levels but may be associated with more toxicity. Quality of life and pain scores were similar between the two treatments. While the literature suggests that a reduction in sCTX may correlate with reduced rate of SREs, given the lack of symptom improvement a switching strategy cannot be recommended. NCT01907880 Clinical trial information: NCT01907880.

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Mark Clemons

Ottawa Hospital Research Institute

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Angel Arnaout

Ottawa Hospital Research Institute

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Brian Hutton

Ottawa Hospital Research Institute

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Christina L. Addison

Ottawa Hospital Research Institute

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Sasha Mazzarello

Ottawa Hospital Research Institute

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Christina Catley

Ottawa Hospital Research Institute

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