Cancer deaths in the United States fell by 26 percent over the past two decades, largely as a result of declines in breast, colon, lung and prostate cancers, according to the latest annual report from the American Cancer Society (ACS).

The drop can largely be explained by less smoking, especially among men. Earlier detection and treatment advances also play a role. “This new report reiterates where cancer control efforts have worked, particularly the impact of tobacco control,” says ACS chief medical officer Otis Brawley, MD. “Strikingly, though, tobacco remains by far the leading cause of cancer deaths today, responsible for nearly 3 in 10 cancer deaths.”

Survival is highest for prostate cancer (99 percent), skin melanoma (92 percent) and breast cancer (90 percent) and lowest for lung cancer (18 percent), liver cancer (18 percent) and pancreatic cancer (8 percent), which are often diagnosed at more advanced stages and are harder to treat.

Despite the improvement, disparities persist: The cancer death rate for African Americans was 14 percent higher than the rate for white people. But the difference was much smaller among people older than 65, suggesting that universal access to Medicare helps overcome disparities in access to care seen at younger ages.