WASHINGTON - The rate of new cancer cases in the United States finally may be inching down -- cautiously optimistic news but a gain that specialists worry could be derailed by economic turmoil.

Death rates from cancer have been dropping slowly for years, thanks to earlier detection and better treatments. But preventing cancer is the ultimate goal, and Tuesday's annual "Report to the Nation" on cancer also shows a small but encouraging change: The rate of new diagnoses among men dropped 1.8 per cent a year between 2001 and 2005.

For women, the dip was just over half a per cent a year.

Also, the cancer death rate among men and women continued to drop, by an average of 1.8 per cent a year through 2005, said the report published in the Journal of the National Cancer Institute.

The improvements are due to gains against some leading cancers -- prostate, colorectal, breast and, for men, lung cancer. But numerous other types still are on the rise, including melanoma and kidney cancer.

Also, Tuesday's report highlights a disappointing missed opportunity: Huge state-by-state variations in anti-smoking policies that translate into big differences in lung cancer. Men in Kentucky die from lung cancer at twice the rate of men in California, for example. California, through higher cigarette taxes and other steps, has logged a 2.8 per cent a year decline in that death rate, compared with less than a per cent a year for Kentucky.

Nor is it clear that the drop in new cases represents a true decrease in cancer, or if some may be due to people skipping screenings that would have caught brewing disease, cautioned American Cancer Society epidemiologist Ahmedin Jemal, who led the report along with government scientists.

But NCI Director Dr. John Niederhuber said the decline seems steady enough to be real, a feat considering that cancer risk jumps with age and the U.S. is rapidly greying.

"This really is quite significant," Niederhuber said. "Some of the things we're doing, we're doing right."

Still, experts questioned if the good trends can survive the bad economy. Consider: The report credits a drop in colorectal cancer to a big increase in colonoscopies between 2000 and 2005. That screening can detect precancerous growths in time to remove them and avoid cancer -- if people have insurance that pays.

Already the NCI has had a below-inflation budget for several years, cutting investment in research to prevent and treat cancer.

"I've had to find about $175 million to take out of our budget, just take it out," said Niederhuber. "It's hard to keep momentum. ... We're chipping away at the bone."

More recent rises in unemployment and poverty add to the concern, warned Dr. Louis Weiner, director of Georgetown University's Lombardi Comprehensive Cancer Center.

"We've had some hard-won gains," Weiner said. "To slow down progress when we're so close to a fundamental understanding of cancer biology that we need to really made advances is really tragic."

Among the report's other findings:

  • New cases of lung cancer dropped about 1.8 per cent a year among men but kept rising among women, about half a per cent a year. That's because smoking rates fell for men before they did for women, so men reaped the benefits sooner. It remains the top cancer killer, but the death rate dropped 1.9 per cent a year for men and 0.9 per cent among women.
  • The rate of new breast cancer dropped about 2.2 per cent a year, due largely to millions of women abandoning hormone replacement therapy starting around 2002. The death rate dropped 1.8 per cent a year.
  • For colorectal cancer, the incidence rate dropped 2.8 per cent a year among men and 2.2 per cent among women, largely due to screening. Early detection and improved care also fuelled a 4.3 per cent a year drop in the death rate for both sexes.
  • Prostate cancer turned a corner, with the incidence rate dropping 4.4 per cent a year between 2001 and 2005 after rising in previous years. The change probably reflects a leveling of prostate screening that had surged in the late 1990s.
  • Melanoma, the deadliest skin cancer, jumped 7.7 per cent a year among men and by nearly three per cent a year among women.
  • Kidney cancer incidence is rising about two per cent a year for both sexes.