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Dive into the research topics where Mark Clemons is active.

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Featured researches published by Mark Clemons.


Lancet Oncology | 2011

Olaparib in patients with recurrent high-grade serous or poorly differentiated ovarian carcinoma or triple-negative breast cancer: a phase 2, multicentre, open-label, non-randomised study

Karen A. Gelmon; Marc Tischkowitz; Helen Mackay; Kenneth D. Swenerton; André Robidoux; Katia Tonkin; Hal Hirte; David Huntsman; Mark Clemons; Blake Gilks; Rinat Yerushalmi; Euan Macpherson; James Carmichael; Amit M. Oza

BACKGROUND Olaparib (AZD2281) is a small-molecule, potent oral poly(ADP-ribose) polymerase (PARP) inhibitor. We aimed to assess the safety and tolerability of this drug in patients without BRCA1 or BRCA2 mutations with advanced triple-negative breast cancer or high-grade serous and/or undifferentiated ovarian cancer. METHODS In this phase 2, multicentre, open-label, non-randomised study, women with advanced high-grade serous and/or undifferentiated ovarian carcinoma or triple-negative breast cancer were enrolled and received olaparib 400 mg twice a day. Patients were stratified according to whether they had a BRCA1 or BRCA2 mutation or not. The primary endpoint was objective response rate by Response Evaluation Criteria In Solid Tumors (RECIST). All patients who received treatment were included in the analysis of toxic effects, and patients who had measurable lesions at baseline were included in the primary efficacy analysis. This trial is registered at ClinicalTrials.gov, number NCT00679783. FINDINGS 91 patients were enrolled (65 with ovarian cancer and 26 breast cancer) and 90 were treated between July 8, 2008, and Sept 24, 2009. In the ovarian cancer cohorts, 64 patients received treatment. 63 patients had target lesions and therefore were evaluable for objective response as per RECIST. In these patients, confirmed objective responses were seen in seven (41%; 95% CI 22-64) of 17 patients with BRCA1 or BRCA2 mutations and 11 (24%; 14-38) of 46 without mutations. No confirmed objective responses were reported in patients with breast cancer. The most common adverse events were fatigue (45 [70%] of patients with ovarian cancer, 13 [50%] of patients with breast cancer), nausea (42 [66%] and 16 [62%]), vomiting (25 [39%] and nine [35%]), and decreased appetite (23 [36%] and seven [27%]). INTERPRETATION Our study suggests that olaparib is a promising treatment for women with ovarian cancer and further assessment of the drug in clinical trials is needed. FUNDING AstraZeneca.


Journal of Clinical Oncology | 2003

Cognitive Function, Fatigue, and Menopausal Symptoms in Women Receiving Adjuvant Chemotherapy for Breast Cancer

Nadine Tchen; Helen G. Juffs; Fiona P. Downie; Qi-long Yi; Hanxian Hu; Irene Chemerynsky; Mark Clemons; Michael Crump; Paul E. Goss; David Warr; Mary E. Tweedale; Ian F. Tannock

PURPOSE There is evidence that cognitive dysfunction, fatigue, and menopausal symptoms may occur in women receiving adjuvant chemotherapy for breast cancer. Here, we determine their incidence and severity, and interrelationships between them and quality of life. PATIENTS AND METHODS In this study, 110 women receiving adjuvant chemotherapy each nominated a female relative, friend, or neighbor (matched by age) as a control; 100 eligible matched pairs were evaluated. Patients and controls completed the following assessments: the High-Sensitivity Cognitive Screen, and the Functional Assessment of Cancer Therapy-General (FACT-G) quality of life scale with subscales for fatigue (FACT-F) and endocrine symptoms (FACT-ES). They also performed tests of attention and reaction time. RESULTS Patients and controls were well matched for age and level of education. There was a higher incidence of moderate or severe cognitive impairment in the patient group (16% v 4%; P =.008). Patients experienced much more fatigue than controls (median FACT-F scores, 31 v 46; P <.0001) and more menopausal symptoms (median FACT-ES scores, 58 v 64; P <.0001). Self-reported quality of life of the patients was poorer than for controls, especially in physical and functional domains (median FACT-G scores, 77 v 93; P <.0001). There was strong correlation between fatigue, menopausal symptoms, and quality of life (P <.0001 for each pair), but none were significantly associated with the presence of cognitive dysfunction. CONCLUSION Adjuvant chemotherapy causes cognitive dysfunction, fatigue, and menopausal symptoms in women with breast cancer. Priority should be given to the study of strategies that might reduce these toxic effects.


European Journal of Cancer | 2001

Randomised phase II trial of pegylated liposomal doxorubicin (DOXIL®/CAELYX®) versus doxorubicin in the treatment of advanced or metastatic soft tissue sarcoma : a study by the EORTC Soft Tissue and Bone Sarcoma Group

Ian Judson; John Radford; M. Harris; Jean-Yves Blay; Q.G.C.M. van Hoesel; A. Le Cesne; A.T. van Oosterom; Mark Clemons; Claus Kamby; C. Hermans; J Whittaker; E Donato di Paola; Jaap Verweij; S Nielsen

CAELYX/DOXIL, pegylated liposomal doxorubicin, has shown antitumour activity and reduced toxicity compared with standard doxorubicin in other tumour types. In this prospective randomised trial, 94 eligible patients with advanced soft-tissue sarcoma (STS) were treated, 50 with CAELYX (50 mg/m(2) by a 1 h intravenous (i.v.) infusion every 4 weeks) and 44 with doxorubicin (75 mg/m(2) by an i.v. bolus every 3 weeks). Histological subtypes were evenly matched, 33% were leiomyosarcoma (CAELYX: 18; doxorubicin: 13). Primary disease sites were well matched. CAELYX was significantly less myelosuppressive, only 3 (6%) patients had grade 3 and 4 neutropenia, versus 33 (77%) on doxorubicin; febrile neutropenia occurred in 7 (16%) patients given doxorubicin, but only 1 (2%) given CAELYX. 37 (86%) patients on doxorubicin had grade 2-3 alopecia, but only 3 (6%) on CAELYX, and the major toxicity with CAELYX was to the skin. Palmar-plantar erythrodysesthesia with CAELYX was grade 1: 4 (8%) patients, grade 2: 11 (22%) patients, grade 3: 9 (18%) patients and grade 4: 1 (2%) patient. Other non-haematological grade 3 and 4 toxicities were rare. Confirmed responses were observed with both agents: CAELYX: complete response (CR) 1 (uterine), partial response (PR) 4 (response rate (RR) 10%); and doxorubicin: CR 1, PR 3 (RR of 9%); with the best response being stable disease (NC) in 16 and 18 patients, respectively. The reason for the low response rate is unknown, but it may be due partly to a high proportion of gastrointestinal stromal tumours. In conclusion, CAELYX has equivalent activity to doxorubicin in STS with an improved toxicity profile and should be considered for further investigation in combination with other agents such as ifosfamide.


Journal of Clinical Oncology | 2012

Prospective Study Evaluating the Impact of Tissue Confirmation of Metastatic Disease in Patients With Breast Cancer

Eitan Amir; Naomi Miller; William Geddie; Orit Freedman; Farrah Kassam; Christine Simmons; Maria Oldfield; George Dranitsaris; George Tomlinson; Andreas Laupacis; Ian F. Tannock; Mark Clemons

PURPOSE Decisions about treatment for women with metastatic breast cancer are usually based on the estrogen (ER), progesterone (PgR), and human epidermal growth factor receptor 2 (HER2) status of the primary tumor. Retrospective data suggest that discordance between primary and metastatic lesions leads to detrimental outcome. This prospective study investigated receptor status of primary tumors and metastases in the same patient and assessed the impact of discordance on patient management and survival. PATIENTS AND METHODS Biopsies of suspected metastases were analyzed for ER, PgR, and HER2. Primary tumors and metastases were analyzed using similar methodology. The treating oncologist indicated a treatment plan before and after biopsy to determine whether the result influenced management. Patients were followed up for progression or death. RESULTS Of 121 women undergoing biopsy, 80% could be analyzed for receptor status. Discordance in ER, PgR, and HER2 between the primary and the metastasis was 16%, 40%, and 10%, respectively. Biopsy led to a reported change of management in 14% of women (95% CI, 8.4% to 21.5%). Fine-needle aspiration and biopsy of bone led to reduced ability to analyze receptors. After a median follow-up of 12 months, there were no trends for an association between receptor discordance and either time to treatment failure or overall survival. CONCLUSION Biopsy of metastases is technically feasible. Clinicians alter immediate management in one of seven patients on the basis of results of the biopsy, and discordance is not then associated with detrimental effects on outcome. Tissue confirmation should be considered in women with breast cancer and suspected metastatic recurrence.


Journal of Clinical Oncology | 2009

Randomized Phase II Study Comparing Two Schedules of Everolimus in Patients With Recurrent/Metastatic Breast Cancer: NCIC Clinical Trials Group IND.163

Susan Ellard; Mark Clemons; Karen A. Gelmon; B. Norris; Hagen F. Kennecke; Stephen Chia; Kathleen I. Pritchard; Andrea Eisen; Ted Vandenberg; Marianne Taylor; Eric Sauerbrei; Moshe Mishaeli; David Huntsman; Wendy Walsh; Martin S. Olivo; Lynn McIntosh; Lesley Seymour

PURPOSE To evaluate the safety and efficacy of oral everolimus, a mammalian target of rapamycin (mTOR) inhibitor, in two different schedules in minimally pretreated patients with metastatic breast cancer and to explore for possible biologic correlates of response. PATIENTS AND METHODS Patients who received no or one prior chemotherapy regimen for metastatic breast cancer were entered onto this multicenter, noncomparative, randomized phase II study of everolimus 10 mg daily versus 70 mg weekly; the multinomial end points of response and progression were evaluated at 8 weeks. A two-stage accrual design was used, with 15 evaluable patients in each schedule in stage 1. Only daily therapy met criteria for continuing, and another 15 patients were added. pAKT, PTEN, carbonic anhydrase 9, estrogen receptor (ER), progesterone receptor, and human epidermal growth factor receptor 2 (HER2) were evaluated for possible correlation with response. RESULTS The most common drug-related toxicities were fatigue, rash, anorexia, diarrhea, stomatitis, cough, and pneumonitis. Pneumonitis occurred at higher than expected rates and seemed to be schedule dependent, with the highest incidence on the daily schedule. Response rate with daily therapy was 12% (95% CI, 3.4% to 28.2%) compared with 0% (95% CI, 0.0% to 20.6%) for weekly therapy. Twenty-seven percent of patients on daily therapy discontinued treatment compared with 13% on weekly therapy (16% v 6% with pneumonitis, respectively). No biologic correlates of response could be identified, although there were trends favoring benefit in ER-positive and HER2-negative metastatic breast cancer. CONCLUSION Oral everolimus has activity in metastatic breast cancer that is schedule dependent. Daily therapy with 10 mg is worthy of further study in this patient population.


Annals of Oncology | 2009

Does confirmatory tumor biopsy alter the management of breast cancer patients with distant metastases

C. Simmons; Naomi Miller; William Geddie; D. Gianfelice; M. Oldfield; G. Dranitsaris; Mark Clemons

Background: Decisions about systemic treatment of women with metastatic breast cancer are often based on estrogen receptor (ER), progesterone receptor (PgR), and Her2 status of the primary tumor. This study prospectively investigated concordance in receptor status between primary tumor and distant metastases and assessed the impact of any discordance on patient management. Materials and methods: Biopsies of suspected metastatic lesions were obtained from patients and analyzed for ER/PgR and Her2. Receptor status was compared for metastases and primary tumors. Questionnaires were completed by the oncologist before and after biopsy to determine whether the biopsy results changed the treatment plan. Results: Forty women were enrolled; 35 of them underwent biopsy, yielding 29 samples sufficient for analysis; 3/29 biopsies (10%) showed benign disease. Changes in hormone receptor status were observed in 40% (P = 0.003) and in Her2 status in 8% of women. Biopsy results led to a change of management in 20% of patients (P = 0.002). Conclusions: This prospective study demonstrates the presence of substantial discordance in receptor status between primary tumor and metastases, which led to altered management in 20% of cases. Tissue confirmation should be considered in patients with clinical or radiological suspicion of metastatic recurrence.


Clinical Breast Cancer | 2009

Survival outcomes for patients with metastatic triple-negative breast cancer: implications for clinical practice and trial design.

Farrah Kassam; Katherine Enright; Rebecca Dent; George Dranitsaris; Jeff Myers; Candi Flynn; Michael Fralick; Ritu Kumar; Mark Clemons

BACKGROUND Clinical experience suggests that many women with triple-negative metastatic breast cancer (MBC) relapse quickly. This has implications for clinical practice and trial design. We evaluated the duration of first-, second-, and third-line chemotherapy as a surrogate for duration of treatment response. PATIENTS AND METHODS We performed a retrospective multicenter chart review of patients with triple-negative MBC receiving palliative chemotherapy. Primary outcome was duration of palliative chemotherapy, and secondary outcome was to identify prognostic variables. RESULTS A total of 111 patients were analyzed. Median age at diagnosis was 51 years (range, 26-82 years). Fourteen percent of patients presented with MBC. Twenty-seven percent received neoadjuvant chemotherapy, and 48% received adjuvant chemotherapy. Median distant disease-free interval (DDFI) was 18 months (range, 0-172 months). At presentation of MBC, 68% had visceral and 71% had multiple sites of disease. Median survival with MBC was 13.3 months (range, 0.8-99.8 months). Median duration of first-line palliative therapy was 11.9 weeks (range, 0-73.1 weeks). Eighty-seven patients (78%) went on to receive second-line therapy with a median duration of 9 weeks (range, 0-120.9 weeks), and 55 (49%) received third-line therapy with a median duration of 4 weeks (range, 0-59 weeks). Multivariate analysis revealed that age < 50 years, ALP > 120 U/L, history of previous chemotherapy, DDFI < 12 months, and visceral presentation were all independently associated with a poor prognosis. CONCLUSION Despite the poorer overall prognosis of patients with triple-negative disease, there remains considerable heterogeneity in individual outcomes. Many women with recurrent triple-negative disease will progress quickly on first-, second-, and third-line palliative treatment. Future clinical trials in this population must take into account their shorter time to progression when determining optimal trial design.


Clinical Breast Cancer | 2008

Insulin-Lowering Effects of Metformin in Women with Early Breast Cancer

Pamela J. Goodwin; Kathleen I. Pritchard; Marguerite Ennis; Mark Clemons; Margaret Graham; I. George Fantus

BACKGROUND Obesity has been associated with poor breast cancer outcomes. Insulin may mediate this effect, interacting with insulin receptors on breast cancer cells. Metformin, a biguanide derivative used in the treatment of diabetes, reduces insulin levels in subjects with type 2 diabetes and other insulin-resistant states. If metformin lowers insulin levels in women with breast cancer, it may also improve breast cancer outcomes. PATIENTS AND METHODS We administered metformin (1500 mg per day) to 32 women with early breast cancer whose baseline insulin levels were at least 45 pmol/L to determine its effect on insulin levels. RESULTS Twenty-two (69%) women completed the 6-month intervention. Four women (12.5%) dropped out because of gastrointestinal side effects; the others withdrew for reasons not related to toxicity. Completers were similar to noncompleters for all baseline characteristics apart from global health, overall physical condition, overall quality of life, physical function, and social function (HRQOL), which was decreased in noncompleters. Metformin significantly lowered fasting insulin levels by 15.8 pmol/L (22.4%; P=.024) and improved insulin sensitivity by 25.6% (P=.018), total cholesterol by 5.3%, and low-density lipoprotein (LDL) cholesterol by 9.1%. Metformin reduced weight by 1.9 kg (2.5%; P=.01), and it had no significant effects on HRQOL or specific gastrointestinal symptoms (appetite, nausea/vomiting, diarrhea, constipation). CONCLUSION Metformin significantly lowers insulin levels, and it improves insulin resistance in nondiabetic women with breast cancer. A phase III randomized trial to evaluate its effects on breast cancer outcomes is recommended.


Cancer Treatment Reviews | 2002

Tamoxifen (‘Nolvadex’): a review

Mark Clemons; Sarah Danson; Anthony Howell

Tamoxifen has been used in the management of breast cancer for over 30 years. Since its introduction for the treatment of advanced breast cancer, its indications have increased to include the treatment of early breast cancer, ductal carcinoma in situ, and more recently for breast cancer chemoprevention. Tamoxifen has a good tolerability profile and moreover, unlike many other endocrine therapies, it is efficacious in both pre- and postmenopausal women. It is the combination of efficacy and tolerability that allows tamoxifen to maintain its position as the hormonal treatment of choice for most patients with oestrogen-receptor positive breast cancer. Ongoing studies will provide further information about the optimal duration of tamoxifen therapy and how it compares with the newer aromatase inhibitors.


Journal of Clinical Oncology | 2006

Pegylated Liposomal Doxorubicin and Trastuzumab in HER-2 Overexpressing Metastatic Breast Cancer: A Multicenter Phase II Trial

Stephen Chia; Mark Clemons; Lee-Ann Martin; A. Rodgers; Karen A. Gelmon; Gregory R. Pond; Lawrence C. Panasci

PURPOSE Cardiotoxicity precludes the concurrent use of doxorubicin and trastuzumab. Because pegylated liposomal doxorubicin (PLD) has equal efficacy but significantly less cardiotoxicity than conventional doxorubicin, this phase II study assessed the rate of cardiotoxicity and efficacy of first-line PLD plus trastuzumab in HER-2-positive metastatic breast cancer (MBC). PATIENTS AND METHODS Women with HER-2-positive, measurable MBC, and a baseline left ventricular ejection fraction (LVEF) > or = 55% were treated with PLD 50 mg/m2 every 4 weeks for six cycles and weekly trastuzumab (4 mg/kg loading dose then 2 mg/kg thereafter). Cardiotoxicity was defined as symptomatic congestive heart failure (CHF) with > or = 10% decline in LVEF to below lower limits of normal, > or = 15% decline in LVEF without symptomatic CHF, or less than 10% LVEF decline to less than 45%. RESULTS Thirty women were enrolled, 13 had received prior adjuvant anthracyclines. A median 5.5 cycles of PLD were administered. Mean baseline LVEF was 62.8%, 59.5% after cycle four, and 58.3% after cycle six. Three patients (10%) developed protocol-defined cardiotoxicity. No patients developed symptomatic CHF. Response rate was 52%, with an additional 38% stable disease rate. At a median follow-up of 13.9 months, the median progression-free survival was 12.0 months; median overall survival has not yet been reached. The most common adverse events were grade 3 hand-foot syndrome (30%) and grade 3/4 neutropenia (27%). CONCLUSION The combination of PLD and trastuzumab is a well tolerated and active regimen in HER-2-positive MBC. Cardiotoxicity was observed, but limited to asymptomatic declines in LVEF. Further evaluation of this combination is warranted.

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Sasha Mazzarello

Ottawa Hospital Research Institute

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Brian Hutton

Ottawa Hospital Research Institute

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Eitan Amir

Princess Margaret Cancer Centre

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Lisa Vandermeer

Ottawa Hospital Research Institute

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George Dranitsaris

Ontario Institute for Cancer Research

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Christina L. Addison

Ottawa Hospital Research Institute

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Angel Arnaout

Ottawa Hospital Research Institute

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Anil A. Joy

Cross Cancer Institute

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