A Disney publicist confirmed the news earlier this week after the TV star lost her battle with the disease at California’s Thousand Oaks hospital on Wednesday.
Her former co-star Tommy Cole, 76, paid a touching tribute to her.
In a statement released to The Hollywood Reporter, he said: “Our Dodo, as we lovingly nicknamed her, always had a smile on her face. She never failed to make us all feel good and we will miss her.”
Doreen rose to fame aged 12 as one of the original Mouseketeers of The Mickey Mouse Club, which aired from 1955 to 1959.
She was hired immediately after impressing judges with a version of a Patti Page hit called Cross Over the Bridge.
Tracey was born in London on April 3, 1943, to her American parents Bessie Hay and Sid Tracey.
The dancer was four when her family returned to the US, and her father opened a dance studio in Hollywood.
She was educated at the John Burroughs High School in Burbank and spent most of her time learning to sing and dance by instructors and performers who worked with her father.
While a Mouseketeer, the performer also starred in the 1956 Disney feature Westward Ho the Wagons! and later toured with the club in Australia.
In the 1960s, the stage veteran visited American military bases in South Vietnam and Thailand.
She was later an associate and publicist of Avant-garde composer and musician Frank Zappa, who passed away in 1993.
Tracey co-starred with her fellow Mouseketeers in several Mickey Mouse Club reunion shows at Disneyland and at Disney conventions throughout the 1980s, 90s and 2000s.
She was also well known for posing nude twice for the men’s magazine Gallery in 1976 and again three years later.
Doreen was married to Robert Washburn, her childhood sweetheart who she met at school.
The couple had a son in 1962 and are believed to have divorced in the same year.
Doreen is survived by her son Bradley and her grandchildren Gavin and Autumn.