Film-maker Duncan and photographer Rodene Ronquillo rushed to the courthouse to become man and wife on November 7, the same day as the US Elections took place.
Forty-three-year-old Duncan has now shaved his head out of solidarity for his 32-year-old wife, who shod her locks ahead of starting chemotherapy on Tuesday.
Source Code director Duncan tweeted to his 125,685 followers: "So I just want to tell you a little story. It may take a few tweets, but I'm hoping you'll forgive me... November was a hell of a month!"
He then when on to recount how he and his fiancée Rodene discovered a lump in her breast. "It was a Sunday, so we had to wait to get an appointment to have the lump biopsied but by Wednesday, we had an answer. Cancer. Stage 2," he continued.
"We were a little overwhelmed by the news: cancer & Election Day, so decided to make it a set, ran down to the courthouse & got married! So cancer, election, marriage. All on one day! Two days later, Ro was in surgery."
The Source Code director told how: "Surgery went really well. Did what we had to do, & were put on a fast track to getting ready for chemo. Starts this coming Tuesday."
He added: "I love my wife more than anyone. She's young as can be. Women are getting breast cancer younger & younger. Women? check yourselves! ..& men?"
For her part, Rodene - who has changed her last name to Jones - added: "Life is fragile, life is precious...you can never be too grateful. Xxoo Make it great."The pretty photographer and Duncan announced their intentions to get married back in June.
Duncan is music icon David's son from his first marriage, to Angie Barnett, an American former model. He was nicknamed Zowie Bowie as a baby, then aged 12 decided he liked to be called Joey, which he later shortened to Joe. By adulthood, he had reverted back to his birth name.
The director has had no contact with his mother since the age of 13, saying that she "didn't have a very positive effect" on his upbringing. He has talked at length about what a great father David has been over the years.
"He's just a wonderful guy and father and I think he understands that I’m a creative person in my own right. He gave me the time and the support to find my feet and the confidence to do what I do," he says.