The 'war on cancer' has led to a reduction in the rate of cancer deaths whether measured against baseline rates in 1970 or in 1990, reports a new study by the American Cancer Society.

According to the study, the downturn in cancer deaths since 1990 is due mostly to reductions in tobacco use, increased screening allowing early detection of several cancers, and modest to large improvements in treatment for specific cancers. The study was published today in PLoS One.

Researchers used nationwide cancer mortality data for the years 1970 through 2006 from the SEER*Stat database, which defines major cancer sites consistently over time in order to facilitate reporting of long term mortality trends.

Researchers studying populations of numerous moth and butterfly species across Papua New Guinea have developed a new technique to study the spread and diet of insect pests--DNA barcoding, which involves the identification of species from a short DNA sequence.

DNA barcodes showed that migratory patterns and caterpillar diets are very dynamic. In one case, a tiny moth that is distributed from Taiwan to Australia, had recently crossed thousands of miles of Pacific Ocean.

The research is detailed in this week's edition of PNAS.

Writing in the latest issue of JAMA, Alec B. O'Connor, associate professor at the University of Rochester Medical Center, says the federal guidelines governing the approval of potential new drugs should be much more stringent. The FDA, according to the commentary, should require studies comparing the effectiveness and safety of a new drug to an established first-line drug when considering a drug for approval.

Currently the agency does not require such studies, known as "active comparator trials," though some large studies of new drugs do include them. In many cases, to gain approval, the main criterion besides safety is that a new drug must be shown to be more effective than placebo.