Hollywood star Dennis Hopper has been diagnosed with prostate cancer and has cancelled travel plans to focus on treatment, his manager said.

The 73-year-old Easy Rider star is being treated in a "special programme" at the University of Southern California, his manager Sam Maydew told the Associated Press. "We're hoping for the best," Maydew said when asked about Hopper's condition and prognosis.

Among the appearances cancelled was a trip to the Australian Centre for the Moving Image in Melbourne, which is set to open an exhibition of his photography next month. Hopper was scheduled to hold a master class on "the artistic process" there.

"Obviously his health is the number one priority and we wish him a very speedy recovery," centre director Tony Sweeney said. "We are saddened that Dennis won't be with us to share in the moment and we look forward with even greater determination to delivering an exciting and successful exhibition".

Hopper was briefly hospitalised for dehydration late last month in New York after suffering flu-like symptoms and stomach pains.

Famous for his starring role in the 1969 hippy road film Easy Rider, which he helped write, Hopper appeared in numerous westerns and nearly 200 other films and television shows stretching back to 1955. He was nominated for Academy Awards for the Easy Rider screen play and for his supporting role in the 1986 basketball movie Hoosiers. He recently finished shooting the second season of the television show Crash, based on the 2004 movie.