The Evil Dead star - who recently revealed he has been diagnosed with "treatable, not curable" cancer - said his new film, Ernie and Emma, was a priority because it has given him "such creative satisfaction".
The 67-year-old actor told the Salem Statesman Journal: "It doesn't change anything for me.
"It makes you prioritise 100 per cent, and for me, the priority is this movie.
"It just gives me such creative satisfaction that, you know, everything else is secondary."
Campbell also told how it was the "most exciting thing ever" working on a film with his wife, Ida Gearon, for the first time.
Ernie and Emma tells the story of widowed pear salesman Ernie Tyler, who travels around scattering his wife's ashes where she asked him to.
The movie is to be screened at Portland's Hollywood Theatre on April 4, and Campbell wants to attend every one of his film's screenings to see people's reactions.
"It's a personal movie. I want to see how it affects people," he said.
"It's a real story that can happen to you.
"I think movies have taken place so much in the fantasy world recently that we've lost a little bit of our understanding of reality."
Earlier in March, Campbell - who is best known for portraying Ash Williams in Sam Raimi's horror series - took to social media to reveal his cancer diagnosis, and admitted it was a "shock" when he was told about it.
"Hi folks, these days, when someone is having a health issue, it's referred to as an 'opportunity', so let's go with that - I'm having one of those," he wrote on X.
"It's also called a type of cancer that's 'treatable' not 'curable'. I apologise if that's a shock - it was to me too."
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