The 63-year-old actress, who died in her Los Angeles home, learned of her condition within the last few months, the report continues.
Charles played girlfriend to the leader of the Scorpions in "Grease," who pulled Sandy (Olivia-Newton John) away from her love Danny (John Travolta) during a nationally-televised school dance competition.
The actress has also appeared on TV series such as 1968's "High Chaparral," as well as "The Flying Nun," "Gunsmoke," "Mod Squad," "Bonanza," "Barnaby Jones" and "The Bionic Woman." Her post-"Grease" credits include 1987's "Magnum, P.I." and "The Incredible Hulk."
Charles also appeared in a 2002 episode of VH-1's "Where Are They Now?" to revisit her saucy dancer persona.