Screening and early diagnosis of breast cancer

Long-term survival in breast cancer currently rests on detection and appropriate therapy at the earliest possible stage, with survival being excellent in patients whose cancers are discovered at a small size and without dissemination. Discovery of lesions at the smallest possible size is therefore desirable. Of the available imaging modalities, only modern mammography has been shown consistently to detect small breast lesions. The efficacy of screening mammography in asymptomatic women has been demonstrated in large-scale trials in women older than 49 years of age and has been strongly supported by follow-up results in the Breast Cancer Detection and Demonstration Project in women aged 40 to 50 years. Mammographic screening has been advocated by the American Cancer Society (ACS) beginning at 40 years of age, while the National Cancer Institute recommends mammographic screening beginning at 50 years of age. The ACS recommends also that breast self-examination begin at 20 years of age. Unfortunately, a great majority of women do not practice breast self-examination, nor do they know that mammography is useful in detecting breast cancer. Further, only a minority of physicians recommend screening mammography, although most recommend breast self-examination and perform physical examination of the breast. Physicians are therefore urged to recommend regular screening to their patients.