Breast Ultrasound vs Mammography: Is the Former a Better Replacement for the Latter? A Comparative Study

Abstract

Breast cancer is the most commonly occurring cancer in women. It is also the second leading cause of cancer death in women. Breast Cancer is the most common and most lethal cancer in Nigeria with an estimated 27,304 new cases in 2012 and which is estimated to increase in further years despite the lack of adequate data. Mortality rates are very high in our locality with approximately 13,960 deaths annually. Mammography is the gold standard for breast cancer screening in developed countries with some evidence showing improved survival particularly among women 50–69 years in some randomized controlled trials in developed countries where breast cancer prevalence is high. Studies gives a mammography sensitivity of (83-86%), a specificity of (48-55.5%), and a diagnostic accuracy of 56-68%. However, mammograms still pose the risk of exposing the breasts to radiation, and is also not well suited for women with dense breasts, implants, fibrocystic breasts, or those on hormone replacement therapy. Breast ultrasound has been used for many years in the characterization of breast lesions, and can also be used to help guide a biopsy needle into an area of the breast for testing. Ultrasound is relied upon significantly since mammographic facilities are few and breast magnetic resonance imaging is either too expensive or unavailable and is it also not limited by breast density. Studies show ultrasound has a sensitivity of (72.2% - 86.3%), and a specificity of (79.8-93.6%). Ultrasound is unable to screen for many types of breast cancer. It is also difficult to detect calcification in the ultrasound of the breast, and this is an early sign of breast cancer. Therefore ultrasound is mainly used in LMIC, where late presentation is most common due to lack of funds because it is cheaper and more portable and it also has a higher sensitivity in women greater than 40 years. In conclusion, this study aims to compare ultrasound and mammography if the former is a better replacement for the latter.