They chanted and held signs urging Premier Jim Prentice to make the cancer treatment facility a priority.
Myka Osinchuk with the Alberta Cancer Foundation said 43 Albertans are diagnosed with the disease every day and the province can't afford to wait.
"Calgary is the only major Canadian city that does not have a comprehensive cancer centre, so Calgary patients who have cancer have to go to no less than five different hospitals to receive their care," Osinchuk said Wednesday.
Protesters banged on drums and chanted "Build it now."
Jenn Birchall, who has Stage 4 breast cancer, inspired people at the rally with her story of perseverance and told the crowd the time to act is now.
"I think it's ridiculous that this hospital has been announced and re-announced and re-announced and I think the government needs to follow through on their promises."
David Swan, Liberal MLA for Calgary-Mountain View, said people he has spoken with are outraged by the government's lack of movement.
Health officials announced plans in March 2013 for a new cancer centre to be built at the Foothills Medical Centre in Calgary to replace the aging Tom Baker Clinic.
They said at the time the new complex would include inpatient beds, cancer diagnostic and treatment technologies, an outpatient facility and dedicated research space.
But in December, a health official said all projects were being assessed due to falling oil prices.
Alberta NDP Leader Rachel Notley said the Tory government has long neglected the health-care needs of Albertans.
"A state-of-the-art cancer centre with the capacity to help southern Albertans has been badly needed for years, and the longer we wait the more we risk compromising their care," she said in a statement Wednesday.
"Cancer is a traumatic enough experience without having to worry if your treatment will be delayed or undermined because of overcrowding and failing infrastructure issues."
(CFFR, The Canadian Press)
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