More Americans than ever before are surviving cancer and rates in general are falling, mostly because fewer people are smoking, the American Cancer Society reported on Wednesday.

However, “When deaths are aggregated by age, cancer has surpassed heart disease as the leading cause of death for persons younger than 85 since 1999,” the group’s 2005 report on cancer reads.

The ACS predicts that 1.372 million Americans will be diagnosed with cancer in 2005 and 570,280 will die of it. This does not include a million cases of two not-very-threatening forms of skin cancer called basal and squamous cell carcinoma.

This compares to 1.368 million cases in 2004 and 563,700 deaths. Overall numbers are up from 2005 because the population is growing in size and growing older, the group said, noting that 76 percent of cancer cases are diagnosed in people over the age of 55.

“The death rate from all cancers combined has decreased by 1.5 percent per year since 1993 among men and by 0.8 percent per year since 1992 among women,” the report points out.

“Overall, the major reason for the decline in mortality rates is progress in tobacco control,” Elizabeth Ward, director of surveillance research for the group, told a telephone news briefing.

She said smoking causes about one-third of all cancer cases, and poor diet and a lack of exercise cause another third.

Cancer is the second-leading cause of death in most developed countries, after heart disease. One in four Americans will die of cancer.

The American Heart Association quickly issued its own reminder that heart disease remains the No. 1 cause of death in the United States and many other countries. Close to 700,000 Americans die of heart disease each year.

“Death rates for all cancers at all three major sites in men have been decreasing,” Ward said, referring to lung cancer, prostate cancer and colon cancer.

But rates of death among men from liver and esophageal cancer have been rising, probably because of obesity, Ward said.

Better detection and treatment have lowered Breast Cancer mortality, but more cases are being diagnosed.

More cases of colon and cervical cancer are also being detected, but good screening can prevent these cancers or catch them at early, more curable stages.

Thyroid cancer cases are up in women - the group predicts there will be 19,190 in 2005 compared to 17,640 in 2004. About 860 women will die of thyroid cancer in 2005.

Ward said it may be due to better screening, or the growing number of X-rays, CAT scans and other radiological scans that people get.

The five-year survival rate for all cancers is 64 percent, up from 50 percent for those first diagnosed in 1976. But the latest data on survival comes from 2000 and rates are probably higher now, the report said.

People need to quit smoking, lose weight and exercise more, Ward said.

Only about 5 percent of all cancers are caused by inherited genetic mutations, Ward said, but there is another preventable cause - viruses, which cause about 17 percent of cancers globally.

They include liver cancer caused by hepatitis B and C, cervical cancer caused by human wart virus or HPV, and Kaposi’s sarcoma caused by human herpesvirus-8 and seen commonly in AIDS patients.

In 2005, the American Cancer Society predicts there will be:

- 232,090 cases of prostate cancer with 30,350 deaths

- 212,930 cases of breast cancer, with 40,870 deaths

- 172,570 cases of lung cancer with 163,510 deaths

- 104,950 cases of colon cancer, with 56,290 deaths

- 59,580 cases of melanoma, with 7,770 deaths

- 56,390 cases of non-Hodgkin’s lymphoma, with 19,200 deaths.