Janet St. James WFAA-TV

This month marks a milestone in medical history.

50 years ago, the first organ transplant was performed. Now, a man well known to sports fans is speaking of his transplant experience to millions in the best way he knows.

Eight months after a liver transplant, Pat Summerall is thrilled to be healthy enough to do what he does best - speaking for a cause he feels more strongly about than football.

"I never thought I'd be doing this again, up walking around again and enjoying life again," the well-known sports broadcaster said. "But it's a miracle ... that's all you can say, it's a miracle."

Summerall's new public service announcement helps commemorate the anniversary of the first successful human organ transplant, a kidney transplant performed two days before Christmas 1954. It took ten years before Parkland Hospital Dallas followed suit and performed the first kidney transplant in Texas.

"Back then, only kidneys were transplanted," said Pam Silvestri of the Southwest Transplant Alliance. "Now, you have hearts and lungs and livers - and livers are split, and we have two lives saved with each transplant. Things have changed dramatically."

Transplants have saved 400,000 lives over the past half-century, including Pat Summerall's.

"I wouldn't be here today if not for the organ donor who saved my life," he said.

After four decades as a professional sports announcer, Summerall is happy to serve as the voice of transplant survivors." That's an honor I never thought I'd achieve, and it surpasses anything I've ever done or achieved," he said. "Every Super Bowl, every Master's tournament, every sporting event I've ever done ... (this) is the most important thing."

Summerall hopes his words, to be aired soon at sporting events across the country, will be the most memorable words he ever says.

In the PSA, he asks, "If you could save a life, would you? You can ... please talk to your family and let them know you want to be a lifesaver."

Because transplants have become so successful, waiting lists have become more popular. Currently, almost 90,000 people are awaiting an organ transplant in the United States.