Cancer is an important public health concern in the United States and around the world. To provide an up-to-date perspective on the occurrence of cancer, the American Cancer Society presents an overview of cancer frequency, incidence, mortality, and survival statistics for 1999.
ESTIMATED NEW CANCER CASES
Because the United States does not have a nationwide cancer registry, exactly how many new cases of cancer are diagnosed in the total United States and individual states each year is not known. Consequently, we estimated the number of new cancer cases occurring annually in the United States from 1979 through 1995 using population data reported by the US Bureau of the Census and age-specific cancer incidence rates collected by the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program.1 We fitted these annual cancer case estimates to an autoregressive quadratic model to forecast the number of cancer cases expected to be diagnosed in the total United States in 1999. This method has been described in detail elsewhere.2
Between 1987 and 1992, the incidence rate of prostate cancer increased 85%, followed by a decline of 28% between 1992 and 1995.3 The sharp increase in incidence followed by the decline in recent years probably reflects extensive use of prostate-specific antigen (PSA) screening in a previously unscreened population and the subsequent increase in diagnoses at an early stage.4 We assumed that the number of prostate cancer cases would approach the pattern of rates in effect before widespread use of PSA screening, and we estimated new cases of prostate cancer for 1999 using a linear projection based on data from 1979 to 1989.
Because cancer incidence rates and case counts for 1979 through 1995 were not available for many states, we could not use the methods mentioned earlier to estimate new cases for individual states. To derive these estimates, we assumed that the ratio of cancer deaths to cancer cases for each state was the same as the ratio for the United States. This method has been described in detail elsewhere.2
ESTIMATED CANCER DEATHS
We estimated the number of cancer deaths expected to occur in the United States in 1999 using underlying cause of death data from death certificates as reported to the National Center for Health Statistics.5 The numbers of cancer deaths occurring annually from 1979 to 1995 were fitted to an autoregressive quadratic model to forecast the number of cancer deaths expected to occur in the total United States in 1999. The estimated number of cancer deaths for each state was calculated with the same modeling procedure used for the total United States. These methods have been described in detail elsewhere.2
Mortality statistics for the leading causes of death and the leading causes of cancer death and cancer mortality rates for 1930 to 1995 were obtained from the National Center for Health Statistics.5 Incidence rates, the probability of developing cancer, and 5-year relative survival rates were obtained from SEER.3,6
EXPECTED NUMBERS OF NEW CANCER CASES
In 1999, we estimate that about 1,221,800 new cases of invasive cancer will be diagnosed in the United States (Table 1). This estimate does not include carcinoma in situ of any site except the urinary bladder, and it does not include basal and squamous cell cancers of the skin. Approximately 1 million cases of basal and squamous cell skin cancers, 39,900 cases of breast carcinoma in situ, and 23,200 cases of melanoma carcinoma in situ are expected to be newly diagnosed in 1999.
Among men, the most common cancers in 1999 are expected to be cancers of the prostate, lung and bronchus, and colon and rectum (Fig. 1). Prostate is the leading site for cancer incidence, accounting for 29% of new cancer cases in men. This year, 179,300 new cases of prostate cancer are expected to be diagnosed.
Among women, the three most commonly diagnosed cancers are expected to be cancers of the breast, lung and bronchus, and colon and rectum (Fig. 1). Cancers occurring at these sites are expected to account for more than 50% of new cancer cases in women. Breast cancer alone is expected to account for 175,000 new cancer cases (29%) in 1999.
TRENDS IN CANCER INCIDENCE
For all sites combined, cancer incidence rates declined an average of −0.7% per year from 1990 to 1995, in contrast to increasing trends in earlier years.7 Similar recent declines are seen among many leading cancer sites (Figs. 3 and 4).
Breast cancer incidence rates have been approximately level during the 1990s; however, they appear to be decreasing in younger women. Decreases in colon and rectum cancer incidence began in the mid-1980s, and today these rates continue to decline significantly, on averase −2.3% per year.7 A downturn in the incidence of lung and bronchus cancer in males began in the late 1980s, and during 1990 to 1995, incidence rates decreased significantly, −2.3% per year. Rates of incidence of lung and bronchus cancer among females are stabilizing. During 1990 to 1995, prostate cancer incidence rates declined significantly, on average-1.0% per year.
EXPECTED NUMBERS OF CANCER DEATHS
In 1999, an estimated 563,100 Americans are expected to die of cancer—more than 1,500 people a day (Table 2). Although most 1999 cancer deaths in men (54%) are expected to be from cancers of the lung and bronchus, prostate, and colon and rectum (Fig. 2), the number of deaths from these three sites appears to be leveling off and may be beginning to decline.
Among women, cancers of the lung and bronchus, breast, and colon and rectum are expected to account for more than half of all cancer deaths in 1999 (Fig. 2). In 1987, lung cancer surpassed breast cancer as the leading cause of cancer death in women and is expected to account for 25% of all cancer deaths in females in 1999. Breast and colon and rectum cancers will account for 16% and 11% of cancer deaths in females, respectively.
TRENDS IN CANCER MORTALITY
After significant increases over the past 70 years, cancer mortality rates for all cancers combined began to decline in the 1990s (Figs. 5 and 6).7 Significant decreases have been seen among males and females, persons younger than 65 years of age, and among whites, African Americans, and Hispanics.
Breast cancer mortality rates in females decreased an average of −1.7% per year during 1990 to 1995; decreases were more pronounced among white women and among younger women. During 1990 to 1995, mortality from cancers of the colon and rectum decreased significantly, on average −1.5% per year.7
Similar to what was seen with trends in incidence, significant decreases in mortality from lung and bronchus cancer have occurred only among males (on average −1.6% per year during 1990 to 1995); rates among females recently have begun to slow and appear to be stabilizing. Prostate cancer mortality decreased an average of −1.1% per year during 1990 to 1995.7
TRENDS IN CANCER BY RACE AND ETHNICITY
Overall rates of cancer incidence vary considerably among racial and ethnic groups (Table 10). African Americans have the highest incidence rates of cancer; they are 60% more likely to develop cancer than are Hispanics and Asian/Pacific Islanders and more than two times more likely to develop cancer than are American Indians. During 1990 to 1995, incidence rates decreased about −1.0% per year among whites and Hispanics, remained relatively stable among African Americans and Asian/Pacific Islanders, and appear to be increasing slightly among American Indians.3
White women are more likely to develop breast cancer than are women of other racial and ethnic groups, and African-American women are more likely to develop cancers of the colon and rectum.3 African-American men have the highest incidence rates of colon and rectum, lung and bronchus, and prostate cancers; they are at least 50% more likely to develop prostate cancer than are men of other racial and ethnic groups.
African Americans are about 34% more likely to die of cancer than are whites and more than two times more likely to die of cancer than are Asian/Pacific Islanders, American Indians, and Hispanics. During 1990 to 1995, mortality rates decreased significantly among African Americans (-0.8% per year), Hispanics (-0.6% per year), and whites (-0.4% per year); remained stable among Asian/Pacific Islanders; and appear to be increasing slightly among American Indians.3
African-American women are more likely to die of breast and colon and rectum cancers than are women of any other racial and ethnic group, and they have approximately the same lung and bronchus cancer mortality rate as white women. Similar to the pattern seen with incidence rates, African-American men have the highest mortality rates of colon and rectum, lung and bronchus, and prostate cancer.3
CANCER IN CHILDREN
Cancer is the second leading cause of death among children aged 1 to 14 years in the United States. Accidents are the most frequent cause of death (Table 12). The most common cancers found in children are leukemias (in particular, acute lymphocytic leukemia), brain and other nervous system cancers, non-Hodgkin's lymphoma, and soft tissue cancers.3 Over the past 20 years, significant improvements have occurred in the 5-year relative survival rate for many childhood cancers. Between 1974–1976 and 1989–1994, survival rates improved by at least 20% for acute lymphocytic and myeloid leukemias, neuroblastoma, non-Hodgkin's lymphoma, soft tissue cancer, and Wilms' tumor (Table 13).
Limitations and Future Challenges
Our estimated numbers of new cancer cases and cancer deaths should be interpreted with caution when used to study trends in cancer incidence and mortality. These estimates may vary considerably from year to year, particularly for rare cancers and for states with smaller populations. We therefore discourage the use of these estimates to track year-to-year changes in cancer occurrence and death.
National Center for Health Statistics mortality rates and SEER cancer incidence rates are generally more informative statistics to use for tracking cancer trends. For example, breast cancer incidence rates increased about 1% per year between 1979 and 1982, increased 4% per year between 1982 and 1987, and were approximately constant between 1987 and 1995. Despite the stabilization of rates during the latter period, the estimates of new breast cancer cases increased between 1988 and 1996.
Our estimates are based on the most currently available cancer incidence and mortality data; however, these data are 4 years old at the time that the estimates are calculated. As such, the effects of large changes occurring in the 4-year interval between 1995 and 1999 cannot be captured by our modeling efforts. Finally, our estimates of new cancer cases are based on incidence rates for the geographic locations that participate in the SEER program and, therefore, may not be representative of the total United States.
Despite these limitations, our estimates do provide an indication of current patterns of cancer in the United States. Such estimates will assist our continuing efforts to reduce the burden of cancer in the United States as the 21st century approaches.
Table Table 1. Estimated New Cancer Cases by Sex, United States, 1999*
Table Table 2. Estimated Cancer Deaths by Sex, United States, 1999*
Table Table 3. Estimated New Cancer Cases by Site and State, US, 1999*
Table Table 4. Estimated Cancer Mortality by Site and State, US, 1999*
Table Table 5. Percentage of Population Developing Invasive Cancers at Certain Ages by Sex, United States, 1993–1995
Table Table 6. Reported Deaths for the 10 Leading Causes of Death by Age and Sex, United States, 1995
Table Table 7. Fifteen Leading Causes of Death, United States, 1995
Table Table 8. Reported Deaths for the Five Leading Cancer Sites for Males by Age, United States, 1995
Table Table 9. Reported Deaths for the Five Leading Cancer Sites for Females by Age, United States, 1995
Table Table 10. Incidence and Mortality Rates* by Site, Race, and Ethnicity, United States, 1990–1995
Table Table 11. Trends in 5-Year Relative Cancer Survival Rates* (%) by Race and Year of Diagnosis, United States, 1974–1994
Table Table 12. Fifteen Leading Causes of Death Among Children Aged 1–14 Years, United States, 1995
Table Table 13. Trends in Cancer Survival for Children Under Age 15 United States, 1974–1994