The past 30 years have seen a steady increase in the number of cancer patients who survive the disease, according to a recent report by the Centers for Disease Control and Prevention (CDC) and the National Cancer Institute (NCI).

In 2001, 9.8 million Americans were cancer survivors, the report said, while in 1971 just 3 million people fell into that category. The agencies used data from a national disease registry, the NCI's Surveillance, Epidemiology, and End Results (SEER) Program, to compile their statistics.

The report attributed the improvements in survival to several factors, including better treatments, better prevention of cancer recurrences and secondary cancers, and lower death rates from other causes. Earlier diagnosis of the disease because of wider screening is also important, but the researchers noted that some people may be living longer with cancer simply because they were diagnosed earlier, not because their outcomes are actually better.

The new report comes on the heels of another major study of cancer trends, the Annual Report to the Nation on the Status of Cancer, prepared by the American Cancer Society, CDC, NCI, and the North American Association of Central Cancer Registries.

That report also found improvements in survival, and lower death rates and incidence rates for many cancers.

The percentage of people in the entire population who die of any type of cancer -- the death rate -- has been decreasing since the early 1990s. Death rates have declined for 11 of the top 15 cancers in men and 8 of the top 15 cancers in women.

Survival rates -- the percentage of people who get cancer and survive at least 5 years -- have also improved substantially for most of the top 15 cancer sites in men and women.

One of the most promising findings of the report was that the lung cancer incidence rate is declining in women for the first time. And lung cancer deaths among women have stabilized, after increasing for many years.

Not all Americans are benefiting from the improvements in cancer detection and treatment, however. The report found wide disparities in survival among racial and ethnic minorities.

Nevertheless, public health experts said the recent findings are hopeful signs in the fight against cancer. The challenge now, the CDC/NCI report said, is to find better ways to help cancer survivors and their families through better understanding of the long-term health and social consequences of surviving cancer.