Nehmat Houssami

Memorial Sloan-Kettering Cancer Center, New York City, New York, United States

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Publications (155)923.97 Total impact

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    ABSTRACT: Background Breast cancer places a heavy burden on the Australian healthcare system, but information about the actual number of women living with breast cancer and their current or future health service needs is limited. We used existing population-based data and innovative statistical methods to address this critical research question in a well-defined geographic region. Methods Breast cancer data from the New South Wales (NSW) Central Cancer Registry and PIAMOD (Prevalence and Incidence Analysis MODel) software were used to project future breast cancer prevalence in NSW. Parametric models were fitted to incidence and survival data, and the modelled incidence and survival estimates were then used to estimate current and future prevalence. To estimate future healthcare requirements the projected prevalence was then divided into phases of care according to the different stages of the survivorship trajectory. Results The number of women in NSW living with a breast cancer diagnosis had increased from 19,305 in 1990 to 48,754 in 2007. This number is projected to increase further to 68,620 by 2017. The majority of these breast cancer survivors will require continued monitoring (31,974) or will be long-term survivors (29,785). About 9% will require active treatment (either initial therapy, or treatment for subsequent metastases or second cancer) and 1% will need end of life care due to breast cancer. Conclusions Extrapolating these projections to the national Australian population would equate to 209,200 women living with breast cancer in Australia in 2017, many of whom will require active treatment or post-treatment monitoring. Thus, careful planning and development of a healthcare system able to respond to this increased demand is required.
    BMC Cancer 12/2014; 2014, 14:936:936. · 3.32 Impact Factor
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    ABSTRACT: Early assessment of response to neoadjuvant chemotherapy (NAC) for breast cancer allows therapy to be tailored; however, optimal response assessment methods have not been established. We estimated the accuracy of ultrasound (US) to predict pathologic complete response (pCR) using common response criteria and pCR definitions, and estimated incremental accuracy over known prognostic variables. Participants undergoing US after two cycles in the GeparTrio trial randomised to no change in NAC were eligible. US response by World Health Organisation (WHO) criteria (1D or 2D) and Response Evaluation Criteria In Solid Tumors (RECIST) was assessed. Four pCR definitions were applied. Sensitivity (correct prediction of pCR), specificity (correct prediction of no-pCR), and diagnostic odds ratios (DORs) were calculated. Areas under the curve (AUCs) were derived from logistic regression including patient variables with and without US. In 832 patients, DORs decreased as pCR definitions became less stringent (p=0.01). For WHO-2D, DORs were: 4.07 (ypT0,ypN0), 3.75 (ypT0/is,ypN0), 3.14 (ypT0/is,ypN+/-), 2.65 (ypT0/is/1a,ypN+/-). DORs did not differ between US criteria (p=0.60). High sensitivity and lower specificity were found for WHO-2D and RECIST; WHO-1D was highly specific with low sensitivity. Sensitivity was highest for WHO-2D predicting ypT0,ypN0 (sensitivity=81.7% specificity=47.6%; vs. 42.3% and 80.4% for WHO-1D). Adding US to models including patient variables (age, T-stage, histology, subtype) improved AUCs for predicting pCR by 2-3%. In conclusion, US accuracy is highest for predicting ypT0,ypN0, shown to be most prognostic of long term survival. WHO-2D and RECIST maximise sensitivity; WHO-1D maximises specificity. US modestly improves the prediction of pCR by patient characteristics. © 2014 Wiley Periodicals, Inc.
    International Journal of Cancer 11/2014; · 5.01 Impact Factor
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    The Breast 09/2014; 23(5):489-502. · 2.58 Impact Factor
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    Annals of Oncology 09/2014; 25(10):871-88. · 6.58 Impact Factor
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    ABSTRACT: To develop, pilot and refine a decision aid (ahead of a randomised trial evaluation) for women around age 50 facing their initial decision about whether to undergo mammography screening.
    BMJ Open 09/2014; 4(9):e006016. · 2.06 Impact Factor
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    ABSTRACT: To compare DBT and FFDM in the classification of microcalcification clusters (MCs) using BI-RADS.
    European Radiology 08/2014; · 4.34 Impact Factor
  • Archives of pathology & laboratory medicine 08/2014; · 2.88 Impact Factor
  • International journal of radiation oncology, biology, physics 08/2014; 89(5):1139–1141. · 4.59 Impact Factor
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    ABSTRACT: Debate about the extent of breast cancer over-diagnosis due to mammography screening has continued for over a decade, without consensus. Estimates range from 0-54%, but many studies have been criticized for having flawed methodology. In this study we used a novel study design to estimate over-diagnosis due to organised mammography screening in South Australia (SA). To estimate breast cancer incidence at and following screening we used a population-based, age-matched case-control design involving 4931 breast cancer cases and 22914 controls to obtain OR for yearly time intervals since women’s last screening mammogram. The level of over-diagnosis was estimated by comparing the cumulative breast cancer incidence with and without screening. The former was derived by applying OR for each time window to incidence rates in the absence of screening, and the latter, by projecting pre-screening incidence rates. Sensitivity analyses were undertaken to assess potential biases. Over-diagnosis was estimated to be 8% (95%CI 2-14%) and 14% (95%CI 8-19%) among SA women aged 45-85 years from 2006-2010, for invasive breast cancer and all breast cancer respectively. These estimates were robust when applying various sensitivity analyses, except for adjustment for potential confounding assuming higher risk among screened than non-screened women, which reduced levels of over-diagnosis to 1% (95%CI -5 -7%) and 8% (95%CI 2-14%) respectively when incidence rates for screening participants were adjusted by 10%. Our results indicate that the level of over-diagnosis due to mammography screening is modest and considerably lower than many previous estimates, including other for Australia. © 2014 Wiley Periodicals, Inc.
    International Journal of Cancer 08/2014; · 6.20 Impact Factor
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    ABSTRACT: IntroductionThis study aimed to evaluate the accuracy of radiographers’ screen-reading mammograms. Currently, radiologist workforce shortages may be compromising the BreastScreen Australia screening program goal to detect early breast cancer. The solution to a similar problem in the United Kingdom has successfully encouraged radiographers to take on the role as one of two screen-readers. Prior to consideration of this strategy in Australia, educational and experiential differences between radiographers in the United Kingdom and Australia emphasise the need for an investigation of Australian radiographers’ screen-reading accuracy.Methods Ten radiographers employed by the Westmead Breast Cancer Institute with a range of radiographic (median = 28 years), mammographic (median = 13 years) and BreastScreen (median = 8 years) experience were recruited to blindly and independently screen-read an image test set of 500 mammograms, without formal training. The radiographers indicated the presence of an abnormality using BI-RADS®. Accuracy was determined by comparison with the gold standard of known outcomes of pathology results, interval matching and client 6-year follow-up.ResultsIndividual sensitivity and specificity levels ranged between 76.0% and 92.0%, and 74.8% and 96.2% respectively. Pooled screen-reader accuracy across the radiographers estimated sensitivity as 82.2% and specificity as 89.5%. Areas under the reading operating characteristic curve ranged between 0.842 and 0.923.Conclusions This sample of radiographers in an Australian setting have adequate accuracy levels when screen-reading mammograms. It is expected that with formal screen-reading training, accuracy levels will improve, and with support, radiographers have the potential to be one of the two screen-readers in the BreastScreen Australia program, contributing to timeliness and improved program outcomes.
    Journal of Medical Radiation Sciences. 08/2014;
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    ABSTRACT: To compare MRI sequences for breast density measurements on a 3T MRI system using IDEAL (Iterative Decomposition of water and fat with Echo Asymmetry and Least squares estimation) as possible physiology-like reference.
    PLoS ONE 06/2014; 9(6):e99027. · 3.53 Impact Factor
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    Nehmat Houssami, Robin M Turner
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    ABSTRACT: Preoperative staging of the axilla in women with invasive breast cancer using ultrasound-guided needle biopsy (UNB) identifies approximately 50% of patients with axillary nodal metastases prior to surgical intervention. Although moderately sensitive, it is a highly specific staging strategy that is rarely falsely-positive, hence a positive UNB allows patients to be triaged to axillary lymph-node dissection (ALND) avoiding potentially unnecessary sentinel node biopsy (SNB). In this review, we extend our previous work through an updated literature search, focusing on studies that report data on UNB utility. Based on data for 10,934 breast cancer patients, sourced from 35 studies, a positive UNB allowed triage of 1,745 cases (simple proportion 16%) to axillary surgical treatment: the utility of UNB was a median 19.8% [interquartile range (IQR) 11.6%-26.7%] across these studies. We also modelled data from a subgroup of studies, and estimated that amongst patients with metastases to axillary nodes, the odds ratio (OR) for high nodal disease burden for a positive UNB versus a negative UNB was 4.38 [95% confidence interval (95% CI): 3.13, 6.13], P<0.001. From this model, the estimated proportion with high nodal disease burden was 58.9% (95% CI: 50.2%, 67.0%) for a positive UNB, whereas the estimated proportion with high nodal disease burden was 24.6% (95% CI: 17.7%, 33.2%) if UNB was negative. Overall, axillary UNB has good clinical utility and a positive UNB can effectively triage to ALND. However, the evolving landscape of axillary surgical treatment means that UNB will have relatively less utility where surgeons have modified their practice to omission of ALND for minimal nodal metastatic disease.
    Cancer biology & medicine. 06/2014; 11(2):69-77.
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    ABSTRACT: Purpose To convene a multidisciplinary panel of breast experts to examine the relationship between margin width and ipsilateral breast tumor recurrence (IBTR) and develop a guideline for defining adequate margins in the setting of breast conserving surgery and adjuvant radiation therapy. Methods and Materials A multidisciplinary consensus panel used a meta-analysis of margin width and IBTR from a systematic review of 33 studies including 28,162 patients as the primary evidence base for consensus. Results Positive margins (ink on invasive carcinoma or ductal carcinoma in situ) are associated with a 2-fold increase in the risk of IBTR compared with negative margins. This increased risk is not mitigated by favorable biology, endocrine therapy, or a radiation boost. More widely clear margins than no ink on tumor do not significantly decrease the rate of IBTR compared with no ink on tumor. There is no evidence that more widely clear margins reduce IBTR for young patients or for those with unfavorable biology, lobular cancers, or cancers with an extensive intraductal component. Conclusions The use of no ink on tumor as the standard for an adequate margin in invasive cancer in the era of multidisciplinary therapy is associated with low rates of IBTR and has the potential to decrease re-excision rates, improve cosmetic outcomes, and decrease health care costs.
    International journal of radiation oncology, biology, physics 05/2014; 88(3):553–564. · 4.59 Impact Factor
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    ABSTRACT: Women with lobular carcinoma in situ (LCIS), atypical lobular hyperplasia (ALH), atypical ductal hyperplasia (ADH), or atypical hyperplasia (AH) are at increased breast cancer (BC) risk. We investigated the accuracy and outcomes of mammography screening in women with histology-proven LCIS, ALH, ADH, or AH history who had screening through Breast Cancer Surveillance Consortium-affiliated mammography facilities. Screens from two cohorts, defined by LCIS/ALH or ADH/AH history, were compared to two cohorts without such history mammogram-matched for age-group, breast density, family history, screen-year, and mammography registry. Overall 359 BCs (277 invasive BC) occurred within 1 year from screening among 52,380 screens. In the LCIS/ALH cohort [versus comparator screens] cancer incidence rates, cancer detection rates (CDR), and interval cancer rates (ICR) were significantly higher (all P < 0.001); although ICR was 4.4/1,000 screens [versus 0.9/1,000; P < 0.001] the proportion that were interval cancers did not differ between compared cohorts (P = 0.43); screening sensitivity was 76.1 % [versus 82.3 %; P = 0.43], however, specificity was significantly lower at 85.1 % [versus 90.7 %; P < 0.0001]. In the ADH/AH cohort [versus comparator] cancer rates and CDR were significantly higher (P < 0.001); although ICR was 2.6/1,000 screens [versus 0.9/1,000; P = 0.002] the proportion that were interval cancers did not differ between cohorts (P = 0.74); screening sensitivity was 81.0 % [versus 82.6 %; P = 0.74] and specificity was lower at 86.2 % [versus 90.2 %; P < 0.0001]. Mammography screening sensitivity in LCIS/ALH and ADH/AH cohorts did not significantly differ from that of matched screens, however, specificity was lower, and ICRs were higher (reflecting underlying cancer rates). Adjunct screening may be of value in these women if it reduces ICR without substantially reducing specificity.
    Breast Cancer Research and Treatment 05/2014; · 4.47 Impact Factor
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    ABSTRACT: Introduction: Women are largely unaware that mammography screening can cause overdetection of inconsequential disease, leading to overdiagnosis and overtreatment of breast cancer. Evidence is lacking about how information on overdetection affects women's breast screening decisions and experiences. This study investigates the consequences of providing information about overdetection of breast cancer to women approaching the age of invitation to mammography screening. Methods and analysis: This is a randomised controlled trial with an embedded longitudinal qualitative substudy. Participants are a community sample of women aged 48–50 in New South Wales, Australia, recruited in 2014. Women are randomly allocated to either quantitative only follow-up (n=904) or additional qualitative follow-up (n=66). Women in each stream are then randomised to receive either the intervention (evidence-based information booklet including overdetection, breast cancer mortality reduction and false positives) or a control information booklet (including mortality reduction and false positives only). The primary outcome is informed choice about breast screening (adequate knowledge, and consistency between attitudes and intentions) assessed via telephone interview at 2 weeks postintervention. Secondary outcomes measured at this time include decision process (decisional conflict and confidence) and psychosocial outcomes (anticipated regret, anxiety, breast cancer worry and perceived risk). Women are further followed up at 6 months, 1 and 2 years to assess self-reported screening behaviour and long-term psychosocial outcomes (decision regret, quality of life). Participants in the qualitative stream undergo additional in-depth interviews at each time point to explore the views and experiences of women who do and do not choose to have screening. Ethics and dissemination: The study has ethical approval, and results will be published in peer-reviewed journals. This research will help ensure that information about overdetection may be communicated clearly and effectively, using an evidence-based approach, to women considering breast cancer screening. Trial registration number: Australian New Zealand Clinical Trials Registry ACTRN12613001035718.
    BMJ Open 05/2014; 4(5):e004990. · 2.06 Impact Factor
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    ABSTRACT: Background There is limited information on the risk of metastatic breast cancer (MBC) to inform younger women, particularly those under 40 years.AimsWe conducted a retrospective analysis of a population-based cohort study to describe the risk, site and prognosis of MBC in young women under 40 years with an initial diagnosis of non-metastatic BC and compare with older women.Methods Data was extracted from the NSW Central Cancer Registry and the Admitted Patient Data Collection database between 2001-2007. Main outcome measures were 5-year cumulative incidence of MBC, prognostic factors for MBC and overall survival (OS) from the date of MBC diagnosis.Results395 (6%) of 6640 women with non-metastatic BC were <40 years. The 5-year cumulative incidence of MBC was 24% (95% CI 20%-29%) for women <40 years with non-metastatic BC, compared to 9% (95% CI 9-10%) for women ≥ 40years. Significant independent risk factors for MBC≤5 years were age <40, regional disease at diagnosis, low socioeconomic status and the presence of other non-breast primary. At first record of MBC, visceral sites were more common for women <40 years than ≥40 (54% vs. 43%; p=0.03). Median survival for women with MBC within 5 years was not significantly different between young and older women (<40 years 18months vs. ≥ 40 years 14months; log rank p=0.21).Conclusions Women with non-metastatic BC before age 40 have a higher 5-year risk of developing MBC than older women. There were no significant differences in median survival following MBC between young and older women.
    Internal Medicine Journal 05/2014; · 1.70 Impact Factor
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    ABSTRACT: Objective We investigated the effect of integrating three-dimensional (3D)-mammography with 2D-mammography on radiologists’ detection measures in the ‘screening with tomosynthesis or standard mammography’ (STORM) trial. Methods STORM, a prospective population-based trial (Trento and Verona breast screening services) compared sequential screen-reading: 2D-mammography alone and integrated 2D/3D-mammography. Radiologist-specific detection measures were calculated for each screen-reading phase for eight radiologists: number of detected cancers, proportion of true-positive (TP) detection, and number and rate of false-positive (FP) recalls (FPR). We estimated the incremental cancer detection rate (CDR). Results There were 59 cancers and 395 false recalls amongst 7292 screening participants. At 2D-mammography screening, radiologist-specific TP detection ranged between 38% and 83% (median 63%; mean 60% and sd 15.4%); at integrated 2D/3D-mammography, TP detection ranged between 78% and 93% (median 87%; mean 87% and sd 5.2%). For all but one radiologist, 2D/3D-mammography improved breast cancer detection (relative to 2D-mammography) ranging between 0% and 54% (median 29%; mean 27% and sd 16.2%) increase in the proportion of detected cancers. Incremental CDR attributable to integrating 3D-mammography in screening varied between 0/1000 and 5.3/1000 screens (median 1.8/1000; mean 2.3/1000 and sd 1.6/1000). Radiologist-specific FPR for 2D-mammography ranged between 1.5% and 4.2% (median 3.1%; mean 2.9% and sd 0.87%), and FPR based on the integrated 2D/3D-mammography read ranged between 1.0% and 3.3% (median 2.4%; mean 2.2% and sd 0.72%). Integrated 2D/3D-mammography screening, relative to 2D-mammography, had the effect of reducing FP and increasing TP detection for most radiologists. Conclusion There was broad variability in radiologist-specific TP detection at 2D-mammography and hence in the additional TP detection and incremental CDR attributable to integrated 2D/3D-mammography; more consistent (less variable) TP-detection estimates were observed for the integrated screen-read. Integrating 3D-mammography with 2D-mammography improves radiologists’ screen-reading through improved cancer detection and/or reduced FPR, with most readers achieving both using integrated 2D/3D mammography.
    European journal of cancer (Oxford, England: 1990) 05/2014; · 4.12 Impact Factor
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    ABSTRACT: We compared detection measures for breast screening strategies comprising single-reading or double-reading using standard 2D-mammography or 2D/3D-mammography, based on the 'screening with tomosynthesis or standard mammography' (STORM) trial. STORM prospectively examined screen-reading in two sequential phases, 2D-mammography alone and integrated 2D/3D-mammography, in asymptomatic women participating in Trento and Verona (Northern Italy) population-based screening services. Outcomes were ascertained from assessment and/or excision histology or follow-up. For each screen-reading strategy we calculated the number of detected and non-detected (including interval) cancers, cancer detection rates (CDRs), false positive recall (FPR) measures and incremental CDR relative to a comparator strategy. We estimated the false:true positive (FP:TP) ratio and sensitivity of each mammography screening strategy. Paired binary data were compared using McNemar's test. Amongst 7292 screening participants, there were 65 (including six interval) breast cancers; estimated first-year interval cancer rate was 0.82/1000 screens (95% confidence interval (CI): 0.30-1.79/1000). For single-reading, 35 cancers were detected at both 2D and 2D/3D-mammography, 20 cancers were detected only with 2D/3D-mammography compared with none at 2D-mammography alone (p<0.001) and 10 cancers were not detected. For double-reading, 39 cancers were detected at 2D-mammography and 2D/3D-mammography, 20 were detected only with 2D/3D-mammography compared with none detected at 2D-mammography alone (p<0.001) and six cancers were not detected. The incremental CDR attributable to 2D/3D-mammography (versus 2D-mammography) of 2.7/1000 screens (95% CI: 1.6-4.2) was evident for single and for double-reading. Incremental CDR attributable to double-reading (versus single-reading) of 0.55/1000 screens (95% CI: -0.02-1.4) was evident for 2D-mammography and for 2D/3D-mammography. Estimated FP:TP ratios showed that 2D/3D-mammography screening strategies had more favourable FP to TP trade-off and higher sensitivity, applying single-reading or double-reading, relative to 2D-mammography screening. The evidence we report warrants rethinking of breast screening strategies and should be used to inform future evaluations of 2D/3D-mammography that assess whether or not the estimated incremental detection translates into improved screening outcomes such as a reduction in interval cancer rates.
    European journal of cancer (Oxford, England: 1990) 04/2014; · 4.12 Impact Factor
  • Nehmat Houssami, Monica Morrow
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    ABSTRACT: The optimal margin in breast-conserving surgery is controversial, and re-excision is common. Pathologic margin assessment is not standardized, and tumor biology and the use of systemic therapy have a major impact on local control. A study-level meta-analysis found no difference in local recurrence for margin widths of 1, 2, and 5 mm, leading a multidisciplinary panel to recommend adoption of no ink on tumor as the standard definition of a negative margin. J. Surg. Oncol. © 2014 Wiley Periodicals, Inc.
    Journal of Surgical Oncology 04/2014; · 2.84 Impact Factor
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    ABSTRACT: Sentinel node biopsy (SNB) has largely replaced axillary lymph node dissection (ALND) as the standard-of-care for nodal staging in invasive breast cancer. Preoperative imaging-based staging of the axilla using ultrasound with selective ultrasound-guided needle biopsy (UNB) is moderately-sensitive and identifies approximately 50% of patients (pooled estimate from meta-analysis 50%; 95% confidence interval=43%-57%) with axillary nodal metastases prior to surgical intervention. It is also a highly specific staging strategy that allows patients to be triaged to ALND based on a positive result (positive predictive value approximates 100%), thus avoiding two-stage axillary surgery and unnecessary SNB. Axillary UNB has a good clinical utility: based on an updated meta-analysis, we found that a median proportion of 18.4% (inter-quartile range=13.3%-27.4%) from 7,097 patients can be effectively triaged to axillary treatment and can avoid SNB. However, the changing algorithm of axillary surgical treatment means that UNB will have relatively less utility where surgeons omit ALND for minimal nodal metastatic disease. Research that allows enhanced application of ultrasound and UNB to specifically identify and biopsy sentinel nodes and to discriminate between patients with minimal versus advanced nodal metastatic involvement is likely to have the most impact on future management of the axilla in breast cancer.
    Anticancer research 03/2014; 34(3):1087-97. · 1.87 Impact Factor

Publication Stats

3k Citations
923.97 Total Impact Points

Institutions

  • 2012–2014
    • Memorial Sloan-Kettering Cancer Center
      • Breast Service
      New York City, New York, United States
    • Western General Hospital
      Edinburgh, Scotland, United Kingdom
    • International Prevention Research Institute
      Lyons, Rhône-Alpes, France
  • 2002–2014
    • University of Sydney
      • School of Public Health
      Sydney, New South Wales, Australia
    • MBF Bioscience
      Williston, Vermont, United States
  • 2013
    • Università degli Studi di Genova
      Genova, Liguria, Italy
  • 2011
    • Bond University
      • Centre for Research in Evidence-Based Practice (CREBP)
      Gold Coast, Queensland, Australia
  • 2005–2011
    • Istituto per lo Studio e la Prevenzione Oncologica (ISPO)
      Florens, Tuscany, Italy
    • Breast Cancer Prevention Institute
      Somerville, New Jersey, United States
  • 2009
    • University of Cambridge
      • Department of Radiology
      Cambridge, ENG, United Kingdom
  • 2005–2009
    • Westmead Hospital
      Sydney, New South Wales, Australia
  • 2008
    • Australasian Society for Breast Disease
      Box Hill, Victoria, Australia
  • 2006–2008
    • Westmead Breast Cancer Institute NSW
      Sydney, New South Wales, Australia
  • 2007
    • Royal Hospital for Women
      Sydney, New South Wales, Australia
  • 2002–2004
    • Sydney Breast Clinic
      Sydney, New South Wales, Australia