Charles M. Schulz, creator of the popular "Peanuts" comic strip gang, has been diagnosed with colon cancer, his publisher said today.

The cancer was discovered when Schulz, who turns 77 Friday, underwent emergency surgery for a blocked abdominal aorta last Tuesday. Officials at Santa Rosa Memorial Hospital declined to comment on his condition, but Schulz's wife, Jean, said doctors were determining the best course of treatment, which can include surgery, radiation or chemotherapy.

Schulz had the surgery after complaining of leg pain and numbness and being rushed to the hospital from his studio in Santa Rosa, 45 miles north of San Francisco. Afterward, he was reported to be resting comfortably.

Since being moved out of the intensive care unit Friday, Schulz has been spending time with his wife of 26 years and his seven children.

Schulz, who still draws each "Peanuts" strip himself and generally works five weeks in advance, has created enough new strips to fill papers through year's end and enough Sunday features to meet demand through Feb. 14, 2000, his publisher said.

"United Feature Syndicate hopes and expects that Mr. Schulz will be able to produce new material for the new year," the New York-based publishing group said in a statement.

"Peanuts," with its popular characters Charlie Brown and Snoopy the dog, appears in some 2,600 newspapers in 75 countries around the world, and it has been the basis for numerous plays, books, recordings and television programs since Schulz created it some five decades ago, making it arguably the most popular comic strip in the world.