According to the American Cancer Society, cancer death rates decreased an average 2.1% a year from 2002 to 2004, nearly twice the annual 1.1% decrease of previous years.¹ The extent of the decline varied by gender (2.6% a year among men and 1.8% among women), type of cancer, and American Indian/Alaska Native (AI/AN) ethnicity. For the population as a whole, cancer death rates have fallen for the majority of the 15 most commonly diagnosed cancers in both men and women. For men, that decline includes a drop in lung, prostate, and colorectal cancers, the 3 leading causes of cancer deaths in men. Women have experienced a decline in 2 of the 3 leading causes of cancer deaths in women?breast and colorectal cancer. Death rates from lung cancer, the number 1 cause of cancer death for both sexes, are still increasing in women but at a much slower rate than in years past.

Cancer incidence rates also declined slightly from 1992 through 2004, for all cancer sites, both sexes, and all races combined. The drop in breast cancer incidence, in particular, was striking—down by 3.5% a year. Some of that decline may be due to decreased use of hormone therapy, which may also contribute to the decline in ovarian cancer rates. Some part of the decline, counterintuitively, may also result from declining mammography rates, with fewer women being screened and a corresponding decline in detection of early cancers.

Declining incidence is not uniform for all types of cancer, however. For men, incidence rates of myeloma and cancers of the liver, kidney, and esophagus continued to increase through 2004. Among women, there have been increases in incidence of non-Hodgkin's lymphoma, melanoma, leukemia, cancers of the bladder and kidney (increasing in women for 29 years), and thyroid cancer, on the rise since 1980.

The report's special section on American Indians and Alaska Natives held some surprises. Despite living with factors—poverty, lower educational levels, higher smoking rates, and poorer access to care—believed to increase cancer vulnerability, this population as a whole has lower cancer death rates than non-Hispanic whites for most cancers. However, rates were higher for cancers of the liver, stomach, cervix, kidney, and gallbladder. Significant regional differences within the AI/AN population were also found, with incidence rates for men and women varying 2-fold among 6 geographic regions of the country. AI/AN men from the Northern Plains region and AI/AN women from Alaska and the Northern and Southern Plains had higher incidence rates than non-Hispanic white men and women in the same areas. For all cancers combined, AI/AN incidence rates were lower in the Southwest and higher in the Plains and Alaska. The significance of these regional variations is unexplained.

1. Espey DK, Wu XC, Swan J, et al. Annual report to the nation on the status of cancer, 1975-2004, featuring cancer in American Indians and Alaska Natives [published online ahead of print October 15, 2007]. Cancer.