Serena Williams says she had a benign branchial cyst "the size of a small grapefruit" removed from her neck and "all is OK."

The retired tennis star, who turned 43 last month, posted Wednesday on social media that she found a lump on her neck in May, had an MRI exam, and was told she didn't need to get it removed if she didn't want to. So, she didn't then, "but it kept growing," Williams said.

After more tests, including a biopsy that was negative for cancer, Williams said, her doctors said she should have a procedure.

She showed video of herself in a hospital bed and wrote: "So this is me removing it. I am feeling so grateful, and fortunate everything worked out, and most of all I'm healthy."

In a separate social media post, she said she is "still recovering, but getting better. Health always comes first."

Williams announced her retirement -- famously eschewing that term and saying instead she was "evolving" away from professional tennis -- shortly before playing in the 2022 U.S. Open, her last tournament.

She won 23 Grand Slam titles in singles, the most by a woman in the sport's professional era, and another 14 in doubles with her older sister Venus. Serena Williams spent more than 300 weeks at No. 1 in the WTA rankings and collected four Olympic gold medals

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