Tennis legend Martina Navratilova announced Monday she is suffering from throat cancer, as well as a recurrence of breast cancer, which she was first diagnosed with in 2010.
"This double whammy is serious but still fixable," Navratilova said in a statement posted to the WTA site. "I'm hoping for a favorable outcome. It's going to stink for a while, but I'll fight with all have I got."
Navratilova, 66, is one of the winningest tennis players of all time. She holds 18 grand slam singles titles as well as 31 grand slam doubles titles and 11 grand slam mixed doubles titles. She was inducted into the International Tennis Hall of Fame in 2000.
Navratilova noticed an enlarged lymph node in her neck in November during the WTA Finals in Fort Worth, Texas, the WTA statement said. In testing soon afterward, doctors discovered stage 1 throat and breast cancer, the organization added.
Navratilova retired from the WTA in 1994, before returning to play doubles for six years starting in 2000.
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Treatment for the cancer will begin next week, and will take place primarily in New York City, the WTA said.
In recent years, Navratilova has worked as a tennis coach and broadcaster, offering her insights to players and audiences alike.
Navratilova will not join Tennis Channel's coverage of the upcoming Australian Open, but she hopes to make some appearances via Zoom soon, the WTA said.
Outspoken on social and political issues for decades, Navratilova made history in 1981 when she became one of the first major sports figures to come out as gay. She married former model Julia Lemigova, Miss USSR 1990 and a cast member on "The Real Housewives of Miami," in 2014. Navratilova appears regularly on the show as well.
Lemigova posted Monday afternoon on Instagram, sharing a photo of the two with their dog, writing, "Thank you to everyone who has reached out to share words of support. Together, we will fight this."
Navratilova posts frequently on social media, weighing in on everything from former President Donald Trump to upcoming Supreme Court elections in Wisconsin.
On Dec. 31, she tweeted, "Here is to a healthy, happy and fair New Year!!"