John Mara, the New York Giants’ co-owner, CEO and president, announced on Monday he was diagnosed with cancer.The 70-year-old longtime Giants executive issued a statement on social media.CLICK HERE FOR MORE SPORTS COVERAGE ON FOXNEWS.COM"I have recently been diagnosed with cancer and have been following the treatment plan recommended by an outstanding team of doctors," Mara said."I’m feeling strong and optimistic, and I’m committed to seeing this through to a positive outcome. I plan to remain active with the team throughout my treatment, and I’m fortunate to be surrounded by incredible support – personally, professionally and medically."Mara asked for privacy while he undergoes treatment.GIANTS' JAXSON DART JOINS TIM TEBOW WITH RARE STATISTICAL FEAT IN FIRST STARTHe joined the Giants in 1991 as general counsel for the team and later was the executive vice president and chief operating officer. His father, Wellington Mara, was the owner of the team until his death in 2005.He oversaw two Giants Super Bowl titles as co-owner with Steve Tisch. Eli Manning led both teams to wins over the New England Patriots.Mara is a third-generation team owner in the NFL. His grandfather, Tim, founded the team in 1925. Wellington and Jack Mara took over the team in 1959 when Tim Mara passed away.The Giants are one of the oldest teams in the NFL, next to the Chicago Bears.Follow Fox News Digital’s sports coverage on X and subscribe to the Fox News Sports Huddle newsletter.