Cancer screening and informed patient discussions. Truth and consequences.

While screening for asymptomatic cancer has become one of the principal clinical activities of primary care physicians, patients are generally not involved directly in screening decisions. To help physicians better communicate the potential benefits and burdens of cancer screening, this article concisely presents information necessary for patients to make a reasoned decision as to whether to proceed with screening: the probability of developing cancer, the operating characteristics of available screening tests, the likelihood that screening will result in an improved outcome for the individual patient, and the potential burdens associated with screening. Screening tests for breast, colorectal, cervical, and prostate cancers are reviewed, including mammography, clinical breast examination, fecal occult blood testing, Papanicolaou smear, digital rectal examination, and prostate-specific antigen. Better communication about cancer screening will promote shared decision making--a central tenet of the physician-patient relationship.