Breast Screening Modalities

Approximately 1 in 17 women in Singapore will develop breast cancer during her lifetime. As the exact cause of the disease remains unknown, prevention is difficult, and at best, we can direct our efforts toward early diagnosis, even at a pre-cancerous stage, and effective treatment.

While the gold standard in screening is a mammogram, other useful modalities to aid in early diagnosis include the high resolution ultrasound and MRI.

In younger, and particularly Asian women, where the breast tissue is characteristically dense, mammograms may fail to detect cancers, which may be obvious on an ultrasound. In my experience, the ultrasound, devoid of radiation, is an effective, popular, and more patient-friendly diagnostic modality which forms an important part of the breast examination, complementing the mammogram. Where carefully applied, the high resolution ultrasound is capable of detecting lesions as small as 2 mm diameter.

The conventional mammogram, and more recently the digital mamogram, is the best modality for detecting micro-calcifications, both benign and malignant. In my practice, mammograms are offered to all women from 35 years and older, for screening. The MRI is offered as an annual. screening tool for only high-risk women (those with a strong family history of breast and/or ovarian cancer, or carriers of mutations in BRCA1 or BRCA2 genes). It is more sensitive than the mammogram in detecting cancers especially in dense breasts. In my practice, the use of the MRI is selective, as false positives do occur and may lead to unnecessary further procedures. At all times, the choice of investigations is discussed between doctor and patient.