Action News sports director Gary Papa, 54, died Friday at the Hospital of the University of Pennsylvania, more than five years after telling viewers that he was losing his hair due to treatment for prostate cancer. His last appearance on Action News was May 13.

Mr. Papa, a Buffalo, N.Y., native who lived in St. Davids, joined WPVI-TV in April 1981 as a weekend sportscaster. His first story was a recap of a 76ers playoff game from Milwaukee. He became Action News' sports director in 1990.

Sunday's annual Run 4 Your Life, a Father's Day benefit on the Parkway for the Foundation for Breast and Prostate Health, will take on additional significance, and his colleagues are expected to attend en masse. Part of the event is known as the Gary Papa Challenge.

Mr. Papa, who was diagnosed with cancer in August 2003, became involved with the foundation in 2004, and "from that minute on, he was the co-chairman of the run," said founder Shelley Schwartz. "He's just been adorable and helpful and creative and up. When he did something, he did it 500 percent. He was a full-of-life fighter."

In July 2007, Mr. Papa announced on the air that he was going through chemotherapy again. At an awards banquet last November for the Delaware County Community Foundation, Mr. Papa told the audience that he was again undergoing chemotherapy and radiation treatments.

Mr. Papa managed to appear upbeat on the air, even during the rare occasions when he addressed his condition. He attended the April 18 memorial service for broadcaster Harry Kalas in a wheelchair, pushed by his old friend Scott Palmer, a former sportscaster at WPVI.

Until last year, Mr. Papa also cohosted the Saturday evening public-affairs show Primetime Weekend, a role he assumed after Jim O'Brien died in a skydiving accident in 1983. The public outpouring yesterday over Mr. Papa's passing was similar to the grief surrounding O'Brien's death; the two men were popular personalities on the city's highest-rated newscast.

"It will never be quite the same around here, but we have a job to do, and we will do it just as well as Gary would expect and demand," anchor Jim Gardner said in a statement from the station. Gardner wept today when talking about his colleague, and the station's newscasts included a series of tributes.

Gardner made a special appearance at the beginning of today's 5 p.m. newscast, co-anchored by Rob Jennings and Monica Malpass. "This is a very difficult day for all of us here," a somber Gardner said.

"This is probably the toughest newscast we've ever done," said Jennings.

Public figures and private citizens praised Mr. Papa. "It's very, very tough to hear this news," Mayor Nutter told Jennings and Malpass.

Other stations acknowledged Mr. Papa's passing on their newscasts, a rare move.

"He was really a part of the soul of that station," said Peter Jaroff, news editor at KYW Newsradio, who as a news producer at 6ABC worked with Mr. Papa for about a quarter-century.

Mr. Papa kept a dizzying schedule despite his disease.

"No matter what - even when he was sick - it was hard to tell when he was on the air and at the station," said Jaroff. "He just kept everything going."

Meteorologist Cecily Tynan, a longtime colleague at 6ABC, described Mr. Papa as a "wonderful person, full of life, full of energy, full of love for his family and his coworkers. We're all going to miss him terribly. . . . He fought the battle as well as he could, but he couldn't fight any longer. He'll stay alive in our hearts and in the viewers' hearts."

Mr. Papa got into broadcasting while a student at Cornell University when he did the morning news for the radio station. After graduating with a major in history and political science, he got married at 20, a union that lasted four years. In 1976, he got his first job, in Steubenville, Ohio, as a news anchor.

His next job was doing weekend sports in Buffalo. Meanwhile, he got a law degree from the University of Buffalo and flirted with the idea of becoming a lawyer.

A longtime theater buff, he tried his hand at acting, starring in a Theater Center Philadelphia production of the comedy P.S. Your Cat Is Dead. An Inquirer critic noted that Mr. Papa "could be more expressive in both his speech and his facial expressions, but he has an appealing stage presence and a good feeling for comedy."

He is survived by his wife, Kathleen; sons Tucker and Nathaniel; his parents; and a brother.

Funeral arrangements have not yet been announced.