Mammography screening

Mammography is the only procedure for detection of breast cancer with proven scientific evidence for usefulness as a screening technique. Whereas curative medicine deals with symptomatic patients, the majority of screening subjects are healthy and non-diseased. Even though breast cancer is the most common form of cancer in women and the specificity of mammography is 90%, most abnormal mammograms are false positives. Another problem of screening is overdiagnosis which is defined as a neoplasm that would never become clinically relevant during the remaining lifetime of the subject. These disadvantages have to be weighed against the benefits of early detection and treatment of breast cancer. Several randomized studies conducted between the 1960s and early-1990s demonstrated a reduction of breast cancer mortality by mammography screening in the range of 20%. Since then progress in treatment modalities has improved the prognosis even in more advanced disease stages. This decreases the survival advantage of early detection; however, treatment at an earlier stage of cancer might reduce the side effects and costs. For women aged 50-70 years the benefits of screening outweigh the disadvantages. Therefore in this age group screening mammography is encouraged and has been implemented as the "Deutsches Mammographie screening programm" (German mammography screening program). For women between 40 and 49 and over 70 years old the advantages of screening depend on the individual breast cancer risk and general-morbidity. Screening by mammography should therefore be an individual choice following careful consideration of the risk-benefit ratio.