Context: Clinical surveys have revealed that incidental detection of renal cell carcinoma is rising because of increased use of imaging procedures.
Objective: To examine incidence, mortality, and survival trends of renal cell and renal pelvis cancers by age, sex, race, and tumor stage at diagnosis.
Design: Calculation of age-adjusted incidence and mortality rates, along with 5-year relative survival rates, using data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program.
Setting and participants: Patients diagnosed as having kidney cancer from 1975 through 1995 in the 9 geographic areas covered by tumor registries in the SEER program, which represent about 10% of the US population.
Main outcome measures: Incidence, mortality, and 5-year relative survival rates by time periods.
Results: The age-adjusted incidence rates for renal cell carcinoma between 1975 and 1995 for white men, white women, black men, and black women were 9.6, 4.4, 11.1, and 4.9 per 100000 person-years, respectively. The corresponding rates for renal pelvis cancer were 1.5, 0.7, 0.8, and 0.5 per 100000 person-years. Renal cell cancer incidence rates increased steadily between 1975 and 1995, by 2.3% annually among white men, 3.1 % among white women, 3.9% among black men, and 4.3% among black women. Increases were greatest for localized tumors but were also seen for more advanced and unstaged tumors. In contrast, the incidence rates for renal pelvis cancer declined among white men and remained stable among white women and blacks. Although 5-year relative survival rates for patients with renal cell cancer improved among whites but not among blacks, kidney cancer mortality rates increased in all race and sex groups.
Conclusions: Increasing detection of presymptomatic tumors by imaging procedures, such as ultrasonography, computed tomography, and magnetic resonance imaging, does not fully explain the upward incidence trends of renal cell carcinoma. Other factors may be contributing to the rapidly increasing incidence of renal cell cancer in the United States, particularly among blacks.