Oct. 25 (Bloomberg) -- William H. Rehnquist, the U.S. chief justice since 1986, is suffering from thyroid cancer, a Supreme Court spokesman said.

Rehnquist, 80, ``was admitted to Bethesda Naval Hospital on Friday, Oct. 22 and underwent a tracheotomy in connection with a recent diagnosis of thyroid cancer,'' spokesman Ed Turner said.

The chief justice is expected to be on the bench when the court next hears arguments, on Nov. 1, Turner said. Rehnquist is due to be released from the hospital this week.

Thyroid cancers generally aren't aggressive and proper treatment allows patients a normal lifespan, according to the Merck Manual of Diagnosis and Therapy, a reference work used by physicians. The cancer rarely spreads.

Still, Rehnquist's illness may renew questions about the future of the high court as the presidential campaign comes to a close. Four justices are in their 70s or 80s. The court hasn't had a vacancy in 10 years, the longest period of continuity since 1823.

Three justices, in addition to Rehnquist, are cancer survivors: Sandra Day O'Connor, John Paul Stevens and Ruth Bader Ginsburg.

Rehnquist was appointed to the court by President Richard Nixon in 1972 and elevated to chief justice by President Ronald Reagan in 1986.

To contact the reporter on this story: Greg Stohr in Washington at gstohr@bloomberg.net.

Last Updated: October 25, 2004 12:45 EDT