Justice William H. Rehnquist did not return to his seat on the U.S. Supreme Court bench Monday as he planned.

Rehnquist, 80, was admitted into a hospital on Saturday, Oct. 23, for treatment of thyroid cancer.

"My plan to return to the office today was too optimistic," Rehnquist said in a statement. He announced he is currently undergoing “radiation and chemotherapy treatments on an outpatient basis” and “recuperating at home.

Rehnquist’s illness has served as a reminder that the next elected president will most likely select the next Chief Justice.

"I don't think it is too much to say that the culture may well hang in the balance with the appointment of Supreme Court justices in the coming years,” said Tony Perkins, president of Family Research Council, in a statement issued after Rehnquist’s hospitalization. “The domestic security of our culture demands a President and Senate that will fight aggressively for judges who strictly interpret the law.”

The Chief Justice may still be issuing opinions on emergency appeals from his house. Rehnquist said he will be keeping up to his work at home.

"I am, and will continue to be, in close contact with my colleagues, my law clerks and members of the Supreme Court staff," he said.