Shabbir M.H. Alibhai, MD, MSc, FRCP(C), Staff Physician, University Health Network, Toronto, ON, Canada, Assistant Professor, Departments of Medicine and Health Policy, Management, and Evaluation, University of Toronto, Research Scientist, Canadian Cancer Society

Abstract
More than one-half of new cancers and over 70% of cancer deaths occur in adults age 65 or older. Systematic screening has been associated with reductions in cancer- related mortality for a variety of cancers, including breast, cervical, and colorectal cancer. Prostate cancer screening remains more controversial despite the recent publication of two large randomized trials of screening. Although guidelines are beginning to address cancer screening specifically among the growing group of seniors age 70 or older, there is virtually no guidance on estimating remaining life expectancy or considering competing causes of mortality (e.g. comorbid medical illness) in this age group. In this article, I review evidence-based guidelines for cancer screening in adults and discuss the limitations of screening studies with respect to older adults. I have also highlighted new evidence and substantive updates to guidelines since the last publication on cancer screening in Geriatrics & Aging five years ago.

Keywords: cancer screening, aged, mass screening.

The accredited CME learning activity based on this article is offered under the auspices of the CE department of the University of Toronto. Participating physicians are entitled to one (1) MAINPRO-M1 credit by completing this program, found online at www.geriatricsandaging.ca/cme

Shabbir M.H. Alibhai, MD, MSc, FRCPC, Department of Medicine, University Health Network; Department of Medicine and Health Policy, Management, and Evaluation, University of Toronto, Toronto, ON.

More than one-half of new cancers and over 70% of cancer deaths in industrialized nations occur in adults age 65 or older. Systematic screening has been associated with reductions in cancer-related mortality for a variety of cancers, including breast, cervical, and colorectal cancer. While increasing numbers of older adults are living beyond 70, few guidelines address cancer screening in this group of older adults. In this article, evidence-based guidelines are reviewed for cancer screening in adults and limitations of screening studies with respect to older adults are discussed. A framework for deciding when to stop cancer screening in older adults is presented based on estimating remaining life expectancy, which incorporates age, comorbidity, and functional status.
Key words: cancer screening, aged, mass screening, overdiagnosis, cancer mortality.