Objective: To describe the incidence rates and sites of cancer, the causes of death, and gender and ethnic variations in patients with cancer in a population of people 90 years of age and older.
Design: Analysis of the 14,088 cases of cancer in this age group, accessioned by the California Cancer Registry from 1988 through 1993, and comparison with those less than age 90.
Measurements: Incidence rates and numbers and percents of cases with various features (gender, ethnicity, site of tumor, stage, causes of death).
Results: The peak age-specific incidence (ASI) of cancer is in the group 80 to 84 years of age. Those 90 to 94 years of age had a higher ASI than any group except those ages 75 to 89. There are ethnic variations in the sites of cancer in people aged 90 or older. Colorectal cancer accounts for more than one-fifth of the new cases of cancer in people 90 or older. In women aged 90 or older, the most common sites of cancers are colorectal, breast, and lymphoma/leukemia. In men of the same age, prostate, colorectal, and lung/bronchus are the most common sites. As age increases, fewer people have their cancers staged, and for lung/bronchus, prostate, and breast, more cancers are first diagnosed in the distant stage in people aged 90 and older. Of the people with cancer who die, the proportion dying of cancer decreases as age increases.
Conclusion: Cancer is a common disease in nonagenarians and centenarians and will be an increasing healthcare problem. Knowledge of its features is essential to those planning, delivering, and financing health care.