title: Opportunistic mammography screening provides effective detection rates in a limited resource healthcare system.
abstract: BACKGROUND
  Breast cancer is the leading cause of cancer deaths in women world-wide. In low and middle income countries, where there are no population-based mammographic screening programmes, late presentation is common, and because of inadequate access to optimal treatment, survival rates are poor. Mammographic screening is well-studied in high-income countries in western populations, and because it has been shown to reduce breast cancer mortality, it has become part of the healthcare systems in such countries. However the performance of mammographic screening in a developing country is largely unknown. This study aims to evaluate the performance of mammographic screening in Malaysia, a middle income country, and to compare the stage and surgical treatment of screen-detected and symptomatic breast cancer.
  
  
  METHODS
  A retrospective review of 2510 mammograms performed from Jan to Dec 2010 in a tertiary medical centre is carried out. The three groups identified are the routine (opportunistic) screening group, the targeted (high risk) screening group and the diagnostic group. The performance indicators of each group is calculated, and stage at presentation and treatment between the screening and diagnostic group is analyzed.
  
  
  RESULTS
  The cancer detection rate in the opportunistic screening group, targeted screening group, and the symptomatic group is 0.5 %, 1.25 % and 26 % respectively. The proportion of ductal carcinoma in situ is 23.1 % in the two screening groups compared to only 2.5 % in the diagnostic group. Among the opportunistic screening group, the cancer detection rate was 0.2 % in women below 50 years old compared to 0.65 % in women 50 years and above. The performance indicators are within international standards. Early-staged breast cancer (Stage 0-2) were 84.6 % in the screening groups compared to 61.1 % in the diagnostic group.
  
  
  CONCLUSIONS
  From the results, in a setting with resource constraints, targeted screening of high risk individuals will give a higher yield, and if more resources are available, population-based screening of women 50 and above is effective. Opportunistic mammographic screening is feasible and effective in a middle income country with performance indicators within international standards. Waiting until women are symptomatic will lead to more advanced cancers.
authors.affiliation: Gleneagles Medical Centre, Penang, Malaysia. ycteh11@gmail.com.
authors.forename: Yew-Ching
authors.initials: YC
authors.lastname: Teh
authors.affiliation: Department of Surgery, University Malaya Medical Centre, Kuala Lumpur, Malaysia. giehooi@yahoo.com.
authors.forename: Gie-Hooi
authors.initials: GH
authors.lastname: Tan
authors.affiliation: Department of Surgery, University Malaya Medical Centre, Kuala Lumpur, Malaysia. nuraish@gmail.com.
authors.forename: Nur Aishah
authors.initials: NA
authors.lastname: Taib
authors.affiliation: Department of Biomedical Imaging, University Malaya Medical Centre, Kuala Lumpur, Malaysia. katt_xr2000@yahoo.com.
authors.forename: Kartini
authors.initials: K
authors.lastname: Rahmat
authors.affiliation: Department of Biomedical Imaging, University Malaya Medical Centre, Kuala Lumpur, Malaysia. westcj@ummc.edu.my.
authors.forename: Caroline Judy
authors.initials: CJ
authors.lastname: Westerhout
authors.affiliation: Department of Biomedical Imaging, University Malaya Medical Centre, Kuala Lumpur, Malaysia. farhana.fadzli@yahoo.com.
authors.forename: Farhana
authors.initials: F
authors.lastname: Fadzli
authors.affiliation: Department of Surgery, University Malaya Medical Centre, Kuala Lumpur, Malaysia. smhoong76@gmail.com.
authors.forename: Mee-Hoong
authors.initials: MH
authors.lastname: See
authors.affiliation: Department of Surgery, University Malaya Medical Centre, Kuala Lumpur, Malaysia. ahshun82@gmail.com.
authors.forename: Suniza
authors.initials: S
authors.lastname: Jamaris
authors.affiliation: Department of Surgery, University Malaya Medical Centre, Kuala Lumpur, Malaysia. chenghar.yip@gmail.com.
authors.forename: Cheng-Har
authors.initials: CH
authors.lastname: Yip
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000453:epidemiology* / Q000601:surgery; D003695:Delivery of Health Care; D055088:Early Detection of Cancer; D005260:Female; D006295:Health Resources; D006801:Humans; D008296:Malaysia / Q000453:epidemiology / Q000208:ethnology; D042361:Mammary Glands, Human / Q000473:pathology; D008327:Mammography; D008403:Mass Screening; D008875:Middle Aged; D009367:Neoplasm Staging; D012189:Retrospective Studies; D062606:Tertiary Care Centers