By GINA HOLLANDAssociated Press Writer WASHINGTON (AP) – Chief Justice William H. Rehnquist, the second-oldest man to preside over the highest U.S. court and its premier conservative figure, is undergoing treatment for thyroid cancer. Rehnquist, 80, underwent throat surgery at Bethesda Naval Hospital in suburban Maryland on Saturday, the Supreme Court announced Monday. It said he expects to be back at work next week when the court will next be in session. Even so, Rehnquist’s hospitalization little more than a week before the election gave new prominence to a campaign issue that has been overshadowed by the war on terrorism. The next president is likely to name several justices to a court that has been deeply divided in recent years on issues as varied as abortion and the 2000 election itself. Rehnquist, a conservative named to the court in 1972 by President Richard Nixon and elevated to chief justice by President Ronald Reagan in 1986, has had a series of health problems. In his gold-striped black robes, he became known to many Americans during the televised impeachment hearings of former President Bill Clinton in the Senate in 1998. In 2002 he missed several court sessions after hurting his knee in a fall at his home. He had surgery to repair a torn tendon. Rehnquist also has struggled with chronic back pain over the years and has spent time in physical therapy. The thyroid gland, located in the neck, produces hormones that help regulate the body’s use of energy. There are several types of thyroid cancer and it was not immediately known which type affected the justice. About 23,600 people develop various types of thyroid cancer each year in the United States. Rehnquist turned 80 earlier this month, a milestone reached by only one other chief justice of the United States. The only older chief justice was Roger Taney, who presided over the high court in the mid-1800s until his death at 87. Word of the cancer came in a two paragraph release from the court. It said Rehnquist was recently diagnosed with cancer and that he was admitted to the hospital on Friday. There were no other details about his condition. Rehnquist has frequently been mentioned as a possible retirement prospect, although he has hired law clerks through June 2006. He turned 80 on Oct. 1, and at a birthday celebration he made no mention of stepping down. No matter who is elected president next week, a vacancy on the high court is likely during the next presidential term. Both President Bush and John Kerry have avoided describing a litmus test for a Supreme Court nomination, although their differences on abortion are cut along partisan lines. The future of the Roe vs. Wade decision legalizing abortion is the most visible symbol of the court’s ideological split. Neither Bush nor Kerry has suggested any names for possible nomination if a Supreme Court seat becomes vacant during the next four years, but they have spoken about judges’ approaches to specific issues. On the subject of gay marriage, Bush said at the Republican convention: “I support the protection of marriage against activist judges, and I will continue to appoint federal judges who know the difference between personal opinion and the strict interpretation of the law.” Kerry has said he would nominate only Supreme Court justices who support abortion rights, and his campaign Web site says he would name “judges with a record of enforcing the nation’s civil rights and anti-discrimination laws.” On Dec. 13, 2000, Rehnquist joined four other Supreme Court justices in reversing Florida’s court-ordered recount of presidential election ballots. The majority of the high court determined there was no time to conduct a lawful recount. That decision resulted in George W. Bush being awarded Florida’s 25 electoral votes, and thus the presidency, over Democrat Al Gore.