Darwin was diagnosed with Hodgkin lymphoma in 2015.
The 34-year-old was on life support in a Brisbane hospital before undergoing chemotherapy treatments at a clinic.
After being released in February, he returned home to his family in Australia.
He is still waiting for news about whether he will live beyond March when his final game of the year against the New York Jets will be broadcast.
Numerous NFL players, including some from the Dallas Cowboys and Seattle Seahawks, are also recovering from cancer treatments.