Baseball legend Ryne Sandberg has been diagnosed with metastatic prostate cancer.
The Baseball Hall of Fame star, 64, who played second base for the Chicago Cubs for most of his career, announced the news in a statement Monday on Instagram.
“To my Chicago Cubs, National Baseball Hall of Fame, extended Baseball Family, the city of Chicago, and all my loyal fans, I want to share some personal news. Last week, I learned that I have been diagnosed with metastatic prostate cancer. I have begun treatment, and I am surrounded by my loving wife Margaret, our incredibly supportive family, the best medical care team, and our dear friends,” wrote Sandberg.
He added, “We will continue to be positive, strong, and fight to beat this. Please keep us in your thoughts and prayers during this difficult time for me and my family.”
The athlete included several images of himself in his post, including one of him giving a thumbs-up while receiving treatment in a hospital.
Nicknamed “Ryno,” Sandberg played for 16 seasons in the MLB. He played as a rookie for the Philadelphia Phillies in 1981 and was traded the following year to the Chicago Cubs, where he became a star.
Sandberg won the 1984 National League Most Valuable Player Award.
He retired from playing baseball in 1997.
More Sports from NBC News
He was inducted into the Baseball Hall of Fame in 2005. Later the same year, the Cubs retired his jersey number, 23.
Sandberg spent parts of three seasons from 2013 to 2015 managing the Philadelphia Phillies.
Metastatic prostate cancer means the cancer has already spread outside the prostate by the time of diagnosis, meaning Sandberg’s cancer is stage 4, according to Mayo Clinic. The prostate is a gland located inside the groin and is important for reproduction.
When prostate cancer spreads, it often goes to the bones, lymph nodes, lungs and liver first, according to Mayo Clinic. Common treatments for metastatic prostate cancer include hormone therapy, chemotherapy and immunotherapy, according to Memorial Sloan Kettering Cancer Center.
For prostate cancers that have spread to parts of the body near the prostate, the five-year survival rate is greater than 99%, according to the American Cancer Society. For prostate cancers that have spread to areas beyond the prostate region, the five-year survival rate is about 38%.