After age 70, the most commonly diagnosed cancers tend to reflect the cumulative effects of aging, environmental exposures, and genetic predispositions that manifest over a lifetime. The cancers most frequently diagnosed in this age group include prostate cancer, lung cancer, colorectal cancer, breast cancer, and skin cancers, among others.
**Prostate cancer** is the most common cancer diagnosed in men over 70. Its incidence rises sharply with age, becoming exceedingly common in this demographic. Many men develop prostate cancer slowly, and some may live with it without symptoms or the need for immediate treatment. However, it remains a leading cause of cancer-related death in older men. The risk factors include age, family history, and race, with screening often involving prostate-specific antigen (PSA) testing and digital rectal exams.
**Lung cancer** is another major cancer diagnosed in older adults, largely due to the long-term effects of smoking and environmental exposures accumulated over decades. It is one of the leading causes of cancer mortality in the elderly. Symptoms often appear late, making early detection challenging. Screening with low-dose CT scans is recommended for certain high-risk groups, including older adults with a history of heavy smoking.
**Colorectal cancer** is common in people over 70, reflecting the importance of regular screening that ideally begins earlier in life but may continue into older age depending on overall health and life expectancy. This cancer arises from polyps in the colon or rectum that can become malignant over time. Symptoms may include changes in bowel habits, blood in stool, and abdominal discomfort.
**Breast cancer** remains a significant concern for women over 70. While the risk increases with age, the biology of breast cancer in older women can differ from that in younger women, often being less aggressive. Mammography screening is typically continued based on individual health status and life expectancy. Hormonal factors, genetics, and lifestyle contribute to risk.
**Skin cancers**, including basal cell carcinoma, squamous cell carcinoma, and melanoma, are very common in older adults due to cumulative sun exposure over a lifetime. Nonmelanoma skin cancers are the most frequently diagnosed cancers overall in the elderly. These cancers often appear on sun-exposed areas such as the face, neck, and hands. Melanoma, though less common, is more dangerous and requires prompt treatment.
Other cancers that are diagnosed in this age group include bladder cancer, pancreatic cancer, and certain types of lymphoma. The incidence of many cancers increases with age because of the accumulation of genetic mutations and the decline in immune surveillance.
Screening and diagnosis in older adults must be individualized, considering overall health, comorbidities, life expectancy, and patient preferences. While screening guidelines often focus on younger populations, many older adults benefit from continued surveillance, especially if they are in good health. Treatment approaches may also differ, balancing effectiveness with quality of life and potential side effects.
In summary, the most common cancers diagnosed after age 70 are prostate, lung, colorectal, breast, and skin cancers, reflecting a combination of lifetime risk factors and the biology of aging. Early detection and tailored management remain key to improving outcomes in this growing population.