(CBS Local) — The nation’s cancer death rate dropped a whopping 27 percent during the last quarter century, according to a new report by the American Cancer Society.

That translates to about 2.6 million fewer cancer deaths total than would have been expected if rates stayed at their peak, which was seen in 1991. “The decline in deaths is largely driven by reductions in smoking and improved treatment, as well as earlier detection for some cancers,” said lead researcher Rebecca Siegel, scientific director of surveillance research at the cancer society.

The drop was driven by huge strides made in treating most common cancers, including breast (down 40 percent), colon (down 53 percent), lung (down 48 percent for men and 23 percent for women) and prostate (down 51 percent).

Overall cancer deaths rose for most of the 20th century, driven mainly by men dying from lung cancer, researchers noted. But since the peak in 1991, the death rate has steadily dropped by approximately 1.5% per year through 2016, according to the study published Tuesday in CA: A Cancer Journal for Clinicians.

Unfortunately, there’s some bad news in the new report. Cancer deaths related to obesity, including cancers of the pancreas and uterus, are rising and prostate cancer deaths are no longer dropping, said Siegel.

Death rates are also up for brain and HPV-related cancers.

And while there’s been a decline in the historic racial gap in cancer death rates, the gap between the rich and poor is widening despite gains made to close the racial gap.