The Impact of Mammographic Breast Cancer Screening in Singapore: A Comparison Between Screen-detected and Symptomatic Women

Background: Breast cancer is the leading cause of cancer death amongst Singapore women. There are few studies evaluating the impact of mammographic screening among Asian women. This study aimed to examine differences in disease stage at presentation and outcome between breast cancer patients who were detected by screening (screen-detected) and those who presented symptomatically (symptomatic) from the experience of a regional hospital in Singapore. We also sought to identify the demographic profile of patients who were less likely to be screen detected. Methods: Retrospective data fpr female patients diagnosed with primary breast cancer and treated from January 2002 - December 2008 were analyzed. Univariate and multivariate analyses were performed to examine the profile of symptomatic as opposed to screen-detected patients and factors that influence presentation at an early disease stage. Survival and recurrence rates were computed by Kaplan-Meier method and compared by log rank test. Results: The study population consisted of 82 screen-detected and 679 symptomatic patients. The screen-detected patients were more likely to present at an earlier stage and have better overall cancer-specific survival as compared to symptomatic patients. Malay women and those without a family history of breast cancer were less likely to be detected by screening. Conclusions: Mammographic screening appeared to enable the detection of oncologically more favorable lesions and conferred better overall cancer-specific survival in Singapore women. There is possibly room for more targeted education efforts to reach out to Malay women and those without a family history of breast cancer to enable earlier disease detection among these individuals through regular breast cancer screening.