CHAPEL HILL — North Carolina coach Roy Williams has had surgery to remove a tumor from his right kidney and might have another procedure to remove a tumor from his left kidney. The school said the Hall of Fame coach underwent a 3½-hour procedure Wednesday morning to remove the first tumor. The tumor's severity is unknown and team spokesman Matt Bowers said test results could be back in about a week. In a news release, the school said doctors discovered the tumor during a physical earlier this month. "The surgery went well and according to plan," said Dr. Eric Wallen, one of the surgeons who performed the procedure. "Coach Williams did great. I fully expect him to coach this season and for years to come. He could miss some practice time if we perform another procedure sometime in October, but he would be able to resume his coaching duties prior to the start of the regular season." The school said several players and assistant coaches will be available to talk with reporters Wednesday afternoon, though no news conference is scheduled. "We will be ready for his return as soon as he is able to do so, but I have stressed to him that he returns only when he has been given the medical approval and he is ready to do that," UNC athletic director Bubba Cunningham said in a statement. "Hopefully that will be soon and for a long, long time to come." Williams, 62, will open practice next month for his 10th season at his alma mater, where he spent 10 years as an assistant to Dean Smith before taking over at Kansas and leading the Jayhawks to four Final Fours. Williams, who has 675 wins in 24 seasons, won NCAA championships with the Tar Heels in 2005 and 2009. The Tar Heels have won the Atlantic Coast Conference regular-season title and reached an NCAA regional final the past two seasons. Williams' surgery was first reported by WRAL in Raleigh, N.C.