Gwendolyn Andrews Nacos was born in New Jersey and immigrated to Canada in 1973. She graduated from Monticello College in Theatre Arts, and Harvard University in Social Sciences. In 1977, she joined The Hudson Bay Company as the first Fashion Director of Menswear and Childrenswear. In 1980, she joined Jandabar Fashions as Merchandise Manager and Sales Director of their Loungewear Division. At the age of 37, she was treated for cancer at the RVH. Since then, she has been a dedicated volunteer leader at the MUHC.

In 1988, she founded Cedars CanSupport, offering free psychological and emotional support, financial assistance and other services to cancer patients. She is a member of the RVH Foundation Board and chairs the Cedars Cancer Institute Dragon Boat Race & Festival. She previously served on the Boards of the MUHC and the Royal Victoria Hospital, as President of The Cedars Cancer Institute, as Chair of the Royal Victoria Hospital Patients’ Committee, on the MUHC Clinical Integration Committee and the MUHC Glen Campus Steering Committee. She is Executive Committee Members, The Best Care for Life Campaign of the MUHC.

Gwen served with her husband Tomo Nacos as the honourary Chair of the Shield of Athena's Annual Art Auction from 2007 to 2009, and joined the Board in 2010.  

In 2011, Gwen serves a Chair of the Shield's 20th Anniversary Celebration.