Background. The Surveillance, Epidemiology, and End Results (SEER) pro
gram of the National Cancer Institute is the most frequently used and
best estimate of the incidence of cancer in the United States. Althoug
h synthetic estimates based on the SEER information can be used to pla
n cancer prevention and intervention programs, the evaluation of these
action programs and the monitoring of cancer incidence in states or o
ther geographic areas requires information on the population for whom
the program is directed. Methods. The age-adjusted incidence of six ca
ncers among persons 65 years of age and older for 1986-1987 living in
the five states participating in the SEER program was compared with th
e incidence derived from hospitalization records contained in the Heal
th Care Financing Administration's (HCFA) administrative data files. A
ge-adjusted incidence rates for 1990 developed from HCFA data for pers
ons living in the nine SEER program areas were contrasted with the inc
idence rates for persons living in the rest of the United States and w
ere developed for each of the 50 states and the District of Columbia.
Results. The comparison of the SEER and HCFA overall age-adjusted canc
er incidence rates in the elderly for 1986-1987 showed that for four o
f the six cancers (breast, colon, lung, and corpus uteri) the rates di
ffered by 5% or less. The HCFA derived rates were 6.37% and 7.65% grea
ter than the SEER rates for prostate and esophagus cancer, respectivel
y. The incidence of cancer between 1986 and 1990 was neither uniformly
higher nor lower among elderly SEER program area residents compared w
ith residents of the rest of the country. Incidence rates varied great
ly among states for each of the cancers. Conclusions. HCFA administrat
ive data can be used by states or other geographic units to monitor th
e incidence of cancer in the elderly as well as to plan and evaluate c
ancer prevention and intervention programs.