Lawrence Paszat

Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada

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Publications (180)972.49 Total impact

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    ABSTRACT: Women with diabetes have higher breast cancer incidence and mortality. The purpose of this study was to examine the impact of diabetes on stage at breast cancer diagnosis, as a possible reason for their higher mortality. Using population-based health databases from Ontario, Canada, this retrospective cohort study examined stage at diagnosis (II, III, or IV vs I) among women aged 20-105 years who were newly diagnosed with invasive breast cancer between 2007 and 2012. We compared those with diabetes to those without diabetes. Diabetes was defined based on medical records using a validated algorithm. Among 38,407 women with breast cancer, 6115 (15.9 %) women had diabetes. Breast cancer patients with diabetes were significantly more likely to present with advanced-stage breast cancer than those without diabetes. After adjustment for mammograms and other covariates, diabetes was associated with a significantly increased risk of Stage II [adjusted odds ratio (aOR) 1.14, 95 % confidence interval (CI) 1.07, 1.22], Stage III (aOR 1.21, 95 % CI 1.11, 1.33), and Stage IV (aOR 1.16, 95 % CI 1.01, 1.33) versus Stage I breast cancer. Women with diabetes had a higher risk of lymph node metastases (aOR 1.16, 95 % CI 1.06, 1.27) and tumors with size over 2 cm (aOR 1.16, 95 % CI 1.06, 1.28). Diabetes was associated with more advanced-stage breast cancer, even after accounting for differences in screening mammogram use and other factors. Our findings suggest that diabetes may predispose to more aggressive breast cancer, which may be a contributor to their higher cancer mortality.
    Breast Cancer Research and Treatment 03/2015; DOI:10.1007/s10549-015-3323-5 · 4.47 Impact Factor
  • JAMA The Journal of the American Medical Association 12/2014; 312(21):2285-6. DOI:10.1001/jama.2014.14038 · 30.39 Impact Factor
  • Rachel Kupets, Yan Lu, Danielle Vicus, Lawrence Paszat
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    ABSTRACT: Objective: To define the patterns of care of women after they have been referred to a colposcopic service. Methods: We carried out this population-based study by linking databases of health care provision for 2010. We defined "colposcopic episodes of care" as a series of colposcopic evaluations beginning at the time of referral for colposcopy because of a new cervical cytology abnormality and continuing until no colposcopy or cytology service had been performed for ≥ 365 days. Results: Cytology reports indicating low-grade squamous intraepithelial lesions and atypical squamous cells of uncertain significance account for 88% of referrals of women for colposcopy. Women aged 20 to 29 had the highest rates of referral and treatments. Up to 87% of women referred for low-grade squamous intraepithelial lesions cytology did not require treatment after colposcopic evaluation, while 54% of women referred for high-grade squamous intraepithelial lesions cytology required treatment. The duration of colposcopic episodes of care in which treatment was carried out lasted up to 327 days, with a median three colposcopic evaluations per episode, whereas episodes of care in which no treatment was carried out lasted up to 190 days with a median of one or two colposcopic examinations per episode. Conclusion: Young women aged 20 to 29 have the highest rates of colposcopic services. Women referred because of cytology showing high-grade squamous intraepithelial lesions in whom treatment is not carried out require more extensive follow-up to ensure that lesions are not missed. We recommend the incorporation of colposcopy services into centralized cervical cancer screening programs.
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    ABSTRACT: Background:Prior randomized, controlled trials (RCTs) indicate patient navigation can boost colorectal cancer (CRC) screening in primary care. The sparse literature on pragmatic trials of interventions designed to increase CRC screening adherence motivated this trial on the impact of a patient navigation intervention that included support for performance of the participants' preferred screening test (colonoscopy or stool blood testing). Methods:Primary-care patients (n = 5240), 50-74 years of age, with no prior diagnosis of bowel cancer, and no record of a recent CRC screening test were identified at the Group Health Centre in northern Ontario. These patients were randomly assigned to an Intervention Group (N = 2629) or a usual care Control Group (N = 2611). Intervention Group participants were contacted by a trained nurse navigator by telephone to discuss CRC screening. Interested patients met with the navigator, who helped them identify and arrange for performance of the preferred screening test. Multivariate analyses were conducted using medical records data to assess intervention impact on screening adherence within 12 months after randomization. Results: Mean patient age was 59 years, and 50% of participants were women. CRC screening adherence was higher in the Intervention Group (35%) compared to the Control Group (20%), a difference that was statistically significant (OR-2.11, CI: 1.87 - 2.39). Conclusions: Preference-based patient navigation increased screening uptake in a pragmatic RCT. Impact: Patient navigation increased CRC screening rates in a pragmatic RCT in proportions similar to those observed in explanatory RCTs.
    Cancer Epidemiology Biomarkers & Prevention 11/2014; DOI:10.1158/1055-9965.EPI-14-0744 · 4.32 Impact Factor
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    ABSTRACT: Objective: The aim of this study was to estimate the effect of cervical screening in the prevention of invasive cervical cancer among age groups, using a population-based case-control study in the province of Ontario, Canada. Methods: Exposure was defined as cervical cytology history greater than 3 months before the diagnosis date of cervical cancer (index date). Cases were women who were diagnosed with cervical cancer between January 1, 1998, and December 31, 2008. Controls were women without a diagnosis of cervical cancer on, or before, December 31, 2008. Two controls were matched to each case on year of birth and income quintile, as of the index date. Conditional logistic regression was used to estimate the odds ratio for having been screened among those with cervical cancer. Results: Cervical cancer screening performed between 3 and 36 months before the index date was protective against invasive cervical cancer in women aged 40 through 69 years. In women younger than 40 years, cervical cancer screening performed 3 to 36 months before the index date was not protective. Conclusions: Cervical screening is associated with a reduced risk for invasive cervical cancer among women older than 40 years. Cervical cancer resources should be focused on maximizing the risk reduction.
    International Journal of Gynecological Cancer 11/2014; 25(1). DOI:10.1097/IGC.0000000000000305 · 1.95 Impact Factor
  • Rachel Kupets, Yan Lu, Danielle Vicus, Lawrence Paszat
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    ABSTRACT: Background: When cervical cytology screening shows atypical squamous cells of unknown significance (ASCUS) or low-grade squamous intraepithelial lesion (LSIL), and cervical cytology screening has not been performed in the previous year, it is recommended that cytology screening be repeated six months later. Women with persistent abnormalities should be referred for colposcopy. We explored provincial databases in Ontario to determine whether these recommendations were always followed. Methods: Cervical cytology reports in Ontario are contained in a provincial database, deterministically linkable to other health services databases, including those recording physician reimbursement claims for colposcopy. We identified all women in Ontario who had a first time diagnosis of ASCUS or LSIL in 2008 or 2009. We searched for additional cytology reports and for colposcopy billing claims during the 24 months following the date of the first abnormal report. We assessed the interaction of socioeconomic status, having abnormal cytology, and having repeat cytology after a report of low-grade abnormal cervical cytology. Results: A total of 74 770 women had a first time report of low-grade abnormal cytology. Among women with ASCUS and LSIL, 69.7% and 60.3%, respectively, underwent repeat cytology. Repeat cytology following ASCUS disclosed normal (68.2%), ASCUS (19.3%), LSIL (10.6%), and high-grade squamous intraepithelial lesion (1.4%); following LSIL, the corresponding percentages were 48.3%, 18.0%, 30.8%, and 2.6%. Of women with ASCUS, 16.2% went directly for colposcopy; 14.0% did not repeat cytology or go for colposcopy. Of women with LSIL, 26.4% went directly for colposcopy but 13.4% had no follow-up. Conclusion: We have demonstrated the potential for substantial improvement in cervical cytology six months after a finding of ASCUS and LSIL. We found that many women with ASCUS and LSIL had unnecessary referrals directly for colposcopy, and we identified a lack of follow-up for one sixth of women with low-grade abnormal cytology.
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    ABSTRACT: Regular screening using guaiac fecal occult blood test (gFOBT) reduces mortality from colorectal cancer (CRC). The objective of this study was to determine whether the addition of a gFOBT kit to a 2nd mailed invitation compared to a 2nd mailed invitation alone increases CRC screening among eligible persons who did not respond to an initial mailed invitation. We conducted a cluster randomized controlled trial, with the physician as the unit of randomization. Participants were persons who had been invited but who had not responded to an invitation for CRC screening in an earlier pilot project. The intervention group received a mailed gFOBT kit and 2nd mailed CRC screening invitation (n=2008) while the control group received a 2nd mailed CRC screening invitation alone (n=1586). The primary outcome was the uptake of gFOBT within 6 months of the 2nd mailing. We found that the uptake of gFOBT was more than twice as high in the intervention group (20.1%) compared to the control group (9.6%). The absolute difference between the 2 groups was 10.5% (95% CI: 7.5 – 13.4%, p=<0.0001). In a subsequent adjusted analysis, participants in the intervention group were twice as likely to complete the test as those in the control group (OR=2.1; 95% CI: 1.6-2.6). These findings suggest that directly mailed gFOBT kits increases CRC screening participation among previous non-responders to a mailed invitation and that approximately 10 gFOBT kits would have to be sent by mail in order to screen 1 additional person. (http://ClinicalTrials.gov: NCT01629004). © 2014 Wiley Periodicals, Inc.
    International Journal of Cancer 09/2014; 136(6). DOI:10.1002/ijc.29191 · 6.20 Impact Factor
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    ABSTRACT: Purpose Whole-breast radiation therapy (XRT) after breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) may decrease the risk of local recurrence, but the optimal dose regimen remains unclear. Past studies administered 50 Gy in 25 fractions (conventional); however, treatment pattern studies report that hypofractionated (HF) regimens (42.4 Gy in 16 fractions) are frequently used. We report the impact of HF (vs conventional) on the risk of local recurrence after BCS for DCIS. Methods and Materials All women with DCIS treated with BCS and XRT in Ontario, Canada from 1994 to 2003 were identified. Treatment and outcomes were assessed through administrative databases and validated by chart review. Survival analyses were performed. To account for systematic differences between women treated with alternate regimens, we used a propensity score adjustment approach. Results We identified 1609 women, of whom 971 (60%) received conventional regimens and 638 (40%) received HF. A total of 489 patients (30%) received a boost dose, of whom 143 (15%) received conventional radiation therapy and 346 (54%) received HF. The median follow-up time was 9.2 years. The median age at diagnosis was 56 years (interquartile range [IQR], 49-65 years). On univariate analyses, the 10-year actuarial local recurrence–free survival was 86% for conventional radiation therapy and 89% for HF (P=.03). On multivariable analyses, age <45 years (hazard ratio [HR] = 2.4; 95% CI: 1.6-3.4; P<.0001), high (HR=2.9; 95% CI: 1.2-7.3; P=.02) or intermediate nuclear grade (HR=2.7; 95% CI: 1.1-6.6; P=.04), and positive resection margins (HR=1.4; 95% CI: 1.0-2.1; P=.05) were associated with an increased risk of local recurrence. HF was not significantly associated with an increased risk of local recurrence compared with conventional radiation therapy on multivariate analysis (HR=0.8; 95% CI: 0.5-1.2; P=.34). Conclusions The risk of local recurrence among individuals treated with HF regimens after BCS for DCIS was similar to that among individuals treated with conventional radiation therapy.
    International journal of radiation oncology, biology, physics 09/2014; DOI:10.1016/j.ijrobp.2014.07.026 · 4.59 Impact Factor
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    ABSTRACT: Since the publication of two randomized controlled trials (RCT) in 1996 demonstrating the effectiveness of fecal occult blood test (FOBT) in reducing colorectal cancer (CRC) mortality, several public health initiatives have been introduced in Ontario to promote FOBT participation. We examined the effect of these initiatives on FOBT participation and evaluated temporal trends in participation between 1994 and 2012.
    BMC Cancer 07/2014; 14(1):537. DOI:10.1186/1471-2407-14-537 · 3.32 Impact Factor
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    ABSTRACT: OBJECTIVES:The sessile serrated adenoma/polyp (SSA/P) is increasingly recognized as an important precursor to colorectal cancer (CRC) and may contribute to proximal postcolonoscopy CRCs. Hyperplastic polyps (HPs) generally follow a more benign course than do SSA/Ps, but they have a similar histologic appearance. Our aims were to identify patient and polyp factors associated with reclassification of HPs as SSA/Ps during a central pathology review and to characterize and compare their subsequent clinical management with other polyps.METHODS:From 2003 to 2008, we prospectively enrolled asymptomatic persons aged 50-74 years in a study of screening colonoscopy. Because criteria for SSA/P diagnosis evolved over our study period, we initiated a second review of all HPs >5 mm in size in 2011, with reclassification of polyps if indicated. Rates of subsequent colonoscopies, polypectomies, and CRCs were identified.RESULTS:We enrolled 2,527 persons who underwent colonoscopy in whom 111 had HPs >5 mm. Thirty-two of the 111 participants (28.8%) with HPs >5 mm had their polyps reclassified as SSA/Ps. There were no significant differences in patient characteristics between those with reclassified SSA/Ps and those who had HPs >5 mm. SSA/Ps were more likely to be proximal (P<0.001) and larger (P<0.007) than the HPs. In all, 48.3% of those with high-risk adenomas received appropriate follow-up compared with 26.1% of those with high-risk SSA/Ps.CONCLUSIONS:Almost 1/3 of recently diagnosed HPs >5 mm were reclassified as SSA/Ps. Patients previously diagnosed with larger HPs in the proximal colon may benefit from a pathologic review to ensure appropriate diagnosis and follow-up.Am J Gastroenterol advance online publication, 8 July 2014; doi:10.1038/ajg.2014.78.
    The American Journal of Gastroenterology 07/2014; 109(11). DOI:10.1038/ajg.2014.78 · 9.21 Impact Factor
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    ABSTRACT: PURPOSE There is limited evidence for the effectiveness of pay for performance despite its widespread use. We assessed whether the introduction of a pay-for-performance scheme for primary care physicians in Ontario, Canada, was associated with increased cancer screening rates and determined the amounts paid to physicians as part of the program. METHODS We performed a longitudinal analysis using administrative data to determine cancer screening rates and incentive costs in each fiscal year from 1999/2000 to 2009/2010. We used a segmented linear regression analysis to assess whether there was a step change or change in screening rate trends after incentives were introduced in 2006/2007. We included all Ontarians eligible for cervical, breast, and colorectal cancer screening. RESULTS We found no significant step change in the screening rate for any of the 3 cancers the year after incentives were introduced. Colon cancer screening was increasing at a rate of 3.0% (95% CI, 2.3% to 3.7%) per year before the incentives were introduced and 4.7% (95% CI, 3.7% to 5.7%) per year after. The cervical and breast cancer screening rates did not change significantly from year to year before or after the incentives were introduced. Between 2006/2007 and 2009/2010, $28.3 million, $31.3 million, and $50.0 million were spent on financial incentives for cervical, breast, and colorectal cancer screening, respectively. CONCLUSIONS The pay-for-performance scheme was associated with little or no improvement in screening rates despite substantial expenditure. Policy makers should consider other strategies for improving rates of cancer screening.
    The Annals of Family Medicine 07/2014; 12(4):317-23. DOI:10.1370/afm.1664 · 4.57 Impact Factor
  • Gastroenterology 05/2014; 146(5):S-404. DOI:10.1016/S0016-5085(14)61462-1 · 13.93 Impact Factor
  • Gastroenterology 05/2014; 146(5):S-176. DOI:10.1016/S0016-5085(14)60622-3 · 13.93 Impact Factor
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    ABSTRACT: Objective To estimate the effect of cervical cancer screening on mortality from cervical cancer in women between the age of 20 to 69 residing in Ontario by 5 year age groups. Methods An Ontario population based case–control study of women between age 20 to 69 was performed. Cases were women who were diagnosed with cervical cancer between January 1,1998 and December 31,2008 who died from cervical cancer within this period. Controls were women without a diagnosis of cervical cancer between January 1,1998 and December 31,2008 who were alive on the case’s date of death. Exposure was defined as cervical cytology history. Conditional logistic regression was used to estimate the strength of association between mortality from cervical cancer and screening in 5 year incremental age intervals. Results We identified 1,052 cases and 10,494 controls. Less than 2.5% of women who died from cervical cancer were under the age of 30. Cervical cancer screening performed 3–36 months prior to the date of diagnosis was found to be protective of mortality from cervical cancer in women over the age of 30(odds ratio = 0.28-0.60;p < 0.05 in all strata). In women under the age of 30 cervical cancer screening was not found to be protective of mortality from cervical cancer(odds ratio = 1.58-2.43;non significant). Conclusion No association between cervical cancer screening and mortality from cervical cancer under the age of 30 was found. This could be due to there being a small or no effect or due to the fact that mortality from cervical cancer under the age of 30 is extremely rare.
    Gynecologic Oncology 05/2014; DOI:10.1016/j.ygyno.2014.02.037 · 3.69 Impact Factor
  • Gastrointestinal Endoscopy 05/2014; 79(5):AB118. DOI:10.1016/j.gie.2014.02.051 · 4.90 Impact Factor
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    ABSTRACT: Estimating risk for advanced proximal neoplasia (APN) based on distal colon findings can help identify asymptomatic persons who should undergo examination of the proximal colon after flexible sigmoidoscopy (FS) screening. We aimed to determine the risk of APN by most advanced distal finding among an average-risk screening population. Prospective, cross-sectional study. Teaching hospital and colorectal cancer screening center. A total of 4651 asymptomatic persons at average risk for colorectal cancer aged 50 to 74 years (54.4% women [n = 2529] with a mean [± standard deviation] age of 58.4 ± 6.2 years). All participants underwent a complete colonoscopy, including endoscopic removal of all polyps. We explored associations between several risk factors and APN. Logistic regression was used to identify independent predictors of APN. A total of 142 persons (3.1%) had APN, of whom 85 (1.8%) had isolated APN (with no distal findings). APN was associated with older age, a BMI >27 kg/m(2), smoking, distal advanced adenoma and/or cancer, and distal non-advanced tubular adenoma. Those with a distal advanced neoplasm were more than twice as likely to have APN compared with those without distal lesions. Distal findings used to estimate risk of APN were derived from colonoscopy rather than FS itself. In persons at average risk for colorectal cancer, the prevalence of isolated APN was low (1.8%). Use of distal findings to predict APN may not be the most effective strategy. However, incorporating factors such as age (>65 years), sex, BMI (>27 kg/m(2)), and smoking status, in addition to distal findings, should be considered for tailoring colonoscopy recommendations. Further evaluation of risk stratification approaches in other asymptomatic screening populations is warranted.
    Gastrointestinal endoscopy 03/2014; 80(4). DOI:10.1016/j.gie.2014.02.001 · 4.90 Impact Factor
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    ABSTRACT: A central tenet of organised cancer screening is that all persons in a target population are invited. The aims of this study were to identify participant and physician factors associated with response to mailed physician-linked invitations (study 1) and to evaluate their effectiveness in an organised colorectal cancer (CRC) screening programme (study 2). 2 studies (study 1-cohort design and study 2-matched cohort design, comprising study 1 participants and a matched control group) were conducted in the context of Ontario's organised province-wide CRC screening programme. 102 family physicians and 11 302 associated eligible patients from a technical evaluation ('the Pilot') of large-scale mailed invitations for CRC screening were included. Matched controls were randomly selected using propensity scores from among eligible patients associated with family physicians in similar practice types as the Pilot physicians. Physician-linked mailed invitation to have CRC screening. Uptake of faecal occult blood test (FOBT) within 6 months of mailed invitation (primary) and uptake of FOBT or colonoscopy within 6 months of mailed invitation (secondary). Factors significantly associated with uptake of FOBT included prior FOBT use, older participant age, greater participant comorbidity and having a female physician. In the matched analysis, Pilot participants were more likely to complete an FOBT (22% vs 8%, p<0.0001) or an FOBT or colonoscopy (25% vs 11%, p<0.0001) within 6 months of mailed invitation than matched controls. The number needed to invite to screen one additional person was 7. Centralised large-scale mailing of physician-linked invitations is feasible and effective in the context of organised CRC screening.
    BMJ Open 03/2014; 4(3):e004494. DOI:10.1136/bmjopen-2013-004494 · 2.06 Impact Factor
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    ABSTRACT: The main goal of treating ductal carcinoma in situ (dcis) is to prevent the development of invasive breast cancer. Most women are treated with breast-conserving surgery (bcs) and radiotherapy. Age at diagnosis may be a risk factor for recurrence, leading to concerns that additional treatment may be necessary for younger women. We report a population-based study of women with dcis treated with bcs and radiotherapy and an evaluation of the effect of age on local recurrence (lr). All women diagnosed with dcis in Ontario from 1994 to 2003 were identified. Treatments and outcomes were collected through administrative databases and validated by chart review. Women treated with bcs and radiotherapy were included. Survival analyses were performed to evaluate the effect of age on outcomes. We identified 5752 cases of dcis; 1607 women received bcs and radiotherapy. The median follow-up was 10.0 years. The 10-year cumulative lr rate was 27% for women younger than 45 years, 14% for women 45-50 years, and 11% for women more than 50 years of age (p < 0.0001). The 10-year cumulative invasive lr rate was 22% for women younger than 45 years, 10% for women 45-50 years, and 7% for women more than 50 years of age (p < 0.0001). On multivariate analyses, young age (<45 years) was significantly associated with lr and invasive lr [hazard ratio (hr) for lr: 2.6; 95% confidence interval (ci): 1.9 to 3.7; p < 0.0001; hr for invasive lr: 3.0; 95% ci: 2.0 to 4.4; p < 0.0001]. An age of 45-50 years was also significantly associated with invasive lr (hr: 1.6; 95% ci: 1.0 to 2.4; p = 0.04). Age at diagnosis is a strong predictor of lr in women with dcis after treatment with bcs and radiotherapy.
    Current Oncology 02/2014; 21(1):e96-e104. DOI:10.3747/co.21.1604 · 1.64 Impact Factor
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    ABSTRACT: Background: ColonCancerCheck (CCC), Canada's first province-wide colorectal cancer (CRC) screening program, was publicly launched in Ontario in April 2008. The objective of this paper is to report on key indicators of CCC Program performance since its inception. Methods: The CCC Program recommends biennial gFOBT for persons 50 to 74 years of age at average risk for CRC and colonoscopy for those at increased risk. Opportunistic screening with colonoscopy is available in Ontario. Five data sources were used to compute indicators of program performance during 2008-11. The indicators computed were FOBT participation, overdue for screening, FOBT positivity, positive predictive value (PPV) of FOBT for CRC, diagnostic follow-up, and CRC detection rate. Results: In 2011, FOBT participation was 29.8% and 46.8% of the target population was overdue for screening. FOBT positivity was higher among men (5.1%) than women (3.5%), and the PPV of FOBT for cancer was 4.3% in 2011. Follow-up colonoscopy within six months of a positive FOBT was completed by 74.6% of Program participants in 2011. The cancer detection rates for FOBT and for colonoscopy in those with a family history were 1.3 per 1,000 and 4.0 per 1,000, respectively, in 2011. Conclusions: These results provide an early indication of Program performance and provide findings relevant to other organized CRC screening programs. Impact: The greater cancer detection rate in those at increased risk due to family history who undergo colonoscopy screening suggests that a strategy of risk stratification will enhance the impact of FOBT-based screening programs.
    Cancer Epidemiology Biomarkers & Prevention 01/2014; 23(3). DOI:10.1158/1055-9965.EPI-13-0956 · 4.56 Impact Factor

Publication Stats

5k Citations
972.49 Total Impact Points

Institutions

  • 2004–2014
    • Sunnybrook Health Sciences Centre
      • • Department of Radiation Oncology
      • • Department of Medicine
      • • Department of Evaluative Clinical Sciences
      • • Division of Medical Oncology and Hematology
      Toronto, Ontario, Canada
  • 2003–2014
    • Institute for Clinical Evaluative Sciences
      Toronto, Ontario, Canada
  • 2000–2014
    • University of Toronto
      • • Institute of Health Policy, Management and Evaluation
      • • Department of Surgery
      • • Department of Radiation Oncology
      • • Institute for Clinical Evaluative Sciences
      • • Department of Medicine
      Toronto, Ontario, Canada
    • Kingston General Hospital
      Kingston, Ontario, Canada
  • 2007–2013
    • Women's College Hospital
      Toronto, Ontario, Canada
    • University of Texas MD Anderson Cancer Center
      • Department of Gynecologic Oncology
      Houston, TX, United States
    • Dalhousie University
      Halifax, Nova Scotia, Canada
    • McMaster University
      • Department of Obstetrics and Gynaecology
      Hamilton, Ontario, Canada
  • 2009–2012
    • University Health Network
      • Division of Gynecologic Oncology
      Toronto, Ontario, Canada
    • University of British Columbia - Vancouver
      • Division of Gynaecologic Oncology
      Vancouver, British Columbia, Canada
  • 1998–2003
    • Cancer Care Ontario
      Toronto, Ontario, Canada
  • 1997–2001
    • Queen's University
      • Department of Oncology
      Kingston, Ontario, Canada