1Division of General Internal Medicine, Department of Medicine, University of California, San Francisco, 1545 Divisadero Street, San Francisco, California 94115, USA.
2Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Nobels väg 12A, 17177 Stockholm, Sweden.
3Departments of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California, San Francisco, 550 16th Street, San Francisco, California 94158, USA.
4Department of Radiology, Geisel School of Medicine at Dartmouth, Dartmouth-Hitchcock Medical Center, 1 Medical Center Drive, Lebanon, New Hampshire 03756, USA.
5Division of Cancer Prevention, National Cancer Institute, 9609 Medical Center Drive, Bethesda, Maryland 20892, USA.
6Departments of Surgery and Radiology, University of California, San Francisco, 1600 Divisadero Street, Box 1710, San Francisco, California 94115, USA.
Several important lessons have been learnt from our experiences in screening for various cancers. Screening programmes for cervical and colorectal cancers have had the greatest success, probably because these cancers are relatively homogenous, slow-growing, and have identifiable precursors that can be detected and removed; however, identifying the true obligate precursors of invasive disease remains a challenge. With regard to screening for breast cancer and for prostate cancer, which focus on early detection of invasive cancer, preferential detection of slower-growing, localized cancers has occurred, which has led to concerns about overdiagnosis and overtreatment; programmes for early detection of invasive lung cancers are emerging, and have faced similar challenges. A crucial consideration in screening for breast, prostate, and lung cancers is their remarkable phenotypic heterogeneity, ranging from indolent to highly aggressive. Efforts have been made to address the limitations of cancer-screening programmes, providing an opportunity for cross-disciplinary learning and further advancement of the science. Current innovations are aimed at identifying the individuals who are most likely to benefit from screening, increasing the yield of consequential cancers on screening and biopsy, and using molecular tests to improve our understanding of disease biology and to tailor treatment. We discuss each of these concepts and outline a dynamic framework for continuous improvements in the field of cancer screening.