Which character is House M.D.’s oncologist and closest friend?

James Wilson is House M.D.’s oncologist and closest friend.

Played by Robert Sean Leonard, Wilson works at Princeton-Plainsboro Teaching Hospital and frequently serves as House’s emotional counterweight. He is compassionate, socially connected, and more willing than House to consider the personal effects of medical decisions.

Wilson and House have a difficult but durable friendship. House often tests Wilson’s patience, borrows his belongings, and dismisses his advice, yet repeatedly relies on him during professional and personal crises.

Wilson’s specialty is oncology, the diagnosis and treatment of cancer. His medical role becomes especially important in the final season, when he receives a terminal cancer diagnosis and the friendship becomes the emotional center of the closing storyline.