Cancer Screening in Older Persons
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Cohen MJ, Gross C, Naeim A. Cancer screening in older persons. Clinical Geriatrics. 2012;20(3):34-42.
This is the fourth article in a continuing series of articles on cancer in older adults. The goal of this series is to highlight how diagnosis and management of cancer in older adults is different from that in younger patients. The previous article in the series, “Palliative Care in Advanced Cancer in Older Adults: Management of Pain, Fatigue, and Gastrointestinal Symptoms,” was published in the November 2011 issue of Clinical Geriatrics®.
Cancer is a leading cause of morbidity and mortality in the United States,1 especially among adults 65 years and older, as nearly 60% of all cancer diagnoses and 70% of cancer deaths occur in this population.2 The geriatric age demographic is expanding dramatically, and by 2030, one in five Americans will be 65 years or older.3 Longevity has also been increasing, along with the prevalence of illnesses like cancer that are more common with age. As longevity and the proportion of elderly Americans continue to grow, the magnitude of the cancer problem is also expected to grow, with older adults bearing most of the additional burden.
In an attempt to approach these issues proactively, more attention is being paid to screening older adults for cancer.2 Although substantial evidence supports screening adults in their fifth and sixth decades of life for colorectal, breast, and cervical cancers, relatively few screening trials have included participants over 70 years of age.4-7 Therefore, in developing current screening guidelines—the majority of which make age-based recommendations—panels extrapolated these data to older adults. The population of elderly adults is heterogeneous, however, complicating such extrapolations.
Elderly individuals differ with respect to life expectancy, number and severity of comorbidities, functional status impairments, and treatment preferences. As such, an individualized approach to cancer screening is appropriate. We summarize existing guidelines for screening the elderly population for breast, colon, prostate, and cervical cancers (Table 1) and outline geriatric issues to consider when making screening recommendations for an older patient.4-16
General Cancer Screening Considerations
The rationale behind cancer screening, which uses diagnostic studies to identify cancer in asymptomatic individuals, is that detecting cancer at an earlier stage will lead to better outcomes. Detecting disease in its preclinical phase theoretically allows enough time to institute therapies more likely to be effective than treatments undertaken after symptoms arise. For most cancers, treatment options and prognosis depend on the stage of the disease at diagnosis.
Currently, evidence supports using mammography to screen for breast cancer; fecal occult blood testing (FOBT), colonoscopy, or flexible sigmoidoscopy to screen for colon cancer; and Papanicolaou (Pap) smears to screen for cervical cancer. Not enough clear evidence is available to recommend or refute routine prostate cancer screening using prostate- specific antigen (PSA) testing or digital rectal examination (DRE) alone or together in the general male population.8
The screening tool and disease type are important factors in determining the appropriateness of screening (Table 2). A screening tool for cancer should be sensitive in its ability to detect disease in its preclinical phase and have a low false-positive rate. The test should be accessible and acceptable to patients, as well as relatively inexpensive and safe. A disease worth screening for should be highly prevalent and impose a significant personal or monetary burden on society, via high rates of morbidity or mortality or great financial costs. Diseases considered good candidates for screening have a lengthy preclinical phase, have effective treatment options available, and have a natural history that enables enough time for therapeutic interventions to be successfully implemented.
Certain individual attributes increase cancer risk and can help determine whether someone is an appropriate candidate for cancer screening. Factors that place someone at higher risk of cancer and indicate high priority for screening include a personal history of cancer or precancerous lesions, a family member with a history of cancer, or a genetic predisposition to cancer. In 2011, a study by Ziogas and colleagues17 found that a patient’s family history of cancer is rarely updated subsequent to an initial physician’s visit, and the authors recommended doing so every 5 to 10 years to ensure the patient receives appropriate cancer screening advice.