Comedian Madeline Kahn had kept the sad news so quiet that most of her colleagues on Cosby didn't even know what was wrong. Still, more observant cast members must have suspected Kahn was undergoing chemotherapy when, looking thin, she began wearing a variety of wigs last spring. Surely they noticed how exhausted Kahn, 57, seemed when she began shooting her fourth Cosby season in August. But after taping just four episodes, she announced she was taking a leave of absence.

On Nov. 3, Kahn, who has nabbed a Tony, an Emmy and two Oscar nominations with her nasally twang and madcap humor, let everyone in on her painful secret. "During the past year, I have been undergoing aggressive treatment for ovarian cancer," she said in a statement. "It is my hope that I might raise awareness of this awful disease and hasten the day that an effective test can be discovered." Kahn went on to commend the work of the New York City-based Ovarian Cancer Research Fund, whose executive director, Jamie Boris, notes, "With ovarian cancer, there is no equivalent of a mammogram or Pap smear. Seventy-five percent of cases are detected late." Such was the case with Kahn's close pal Gilda Radner, who died of the disease in 1989.

Best known for her hilarious screen collaborations with Mel Brooks (Blazing Saddles, High Anxiety), Kahn is waging a determined fight. On Oct. 10, she married her longtime beau, attorney John Hansbury, 49. And the Cosby cast is hoping she'll return after the new year. "Her spirits are wonderful," says friend Eric Mendelsohn, who directed her in the upcoming film Judy Berlin. "Madeline is indomitable."