Cecilia A. Wilkinson, who worked with some of Southern California’s leading companies in investor relations and corporate communications, has died. She was 57.

Wilkinson was a principal of L.A.-based PondelWilkinson Inc. She died on Wednesday at her Manhattan Beach home after a 20-month battle with pancreatic cancer.

During her 25 years with the firm, she advised companies on issues ranging from merger and acquisition communications, corporate crises, news media relations and shareholder communications. Her clients included Neutrogena, Souplantation, the Outdoor Channel, Amgen, the W.M. Keck Foundation, Long Beach Grand Prix and Aames Financial Corp.

“Cecilia’s passion for her work and dedication to our firm served as a source of inspiration to all of us,” said Roger S. Pondel, president of PondelWilkinson. “Our staff and our industry mourn the loss of an esteemed colleague, a valued mentor and a treasured friend.”

Wilkinson was born June 30, 1949, in Long Beach, and earned master’s and bachelor’s degrees in public relations at the University of Southern California. She was a member of the USC Annenberg School for Communication Board of Councilors and served as an officer and director of Annenberg’s Communications Associates. Wilkinson was named to the Board of Governors of the USC General Alumni Association in 2004.

She is survived by her daughter, Mallory, sister, Nela, brother, Richard, her mother, Amanda, and by nieces and nephews.

A memorial service will be 10 a.m. Friday, Oct. 6, at American Martyrs Catholic Church, 624 15th St., Manhattan Beach. In lieu of flowers, memorial donations may be sent to the USC Annenberg School of Journalism, attn. Michelle Clark, Annenberg School for Communication, ASC 304, University of Southern California, Los Angeles, 90089; or the John Wayne Cancer Institute, Pancreatic Cancer Research, 2200 Santa Monica Blvd., Santa Monica, 90404.