What cancer is Rocky diagnosed with in Creed?

In Creed, Rocky is diagnosed with non-Hodgkin's lymphoma. The diagnosis arrives after Rocky becomes ill while training Adonis, turning the mentor’s physical decline into the film’s most personal conflict.

Rocky initially refuses chemotherapy because he associates cancer treatment with the death of his wife, Adrian, who had ovarian cancer. He also feels isolated after the deaths of Apollo, Mickey, Paulie and Adrian, and after becoming estranged from his son. His resignation makes him appear ready to accept death rather than fight again.

Adonis reacts angrily when he learns the truth, accusing Rocky of not truly considering them family. That confrontation affects both men: Adonis temporarily withdraws from training, while Rocky eventually agrees to treatment. By the end of the film, Rocky is frail but improving, and he climbs the Philadelphia Museum of Art steps with Adonis.

A frequent confusion is Adrian’s illness. Adrian had ovarian cancer in the Rocky story; Rocky’s illness in Creed is non-Hodgkin's lymphoma, a cancer of the lymphatic system.