Kushner Says He Was Treated for Thyroid Cancer While in White House

“This was a personal problem and not for public consumption,” he wrote. “With the exception of Ivanka, Avi, Cassidy and Mulvaney, I didn’t tell anyone at the White House — including the president,” he wrote, referring to his wife, Ivanka Trump; two of his aides; and Mick Mulvaney, then the White House chief of staff.

A person close to Mr. Mulvaney, after learning of the book’s reference to him, said he did not recall being told…