Self-help author Spencer Johnson dies

US self-help author whose book Who Moved My Cheese sold millions and made him famous, has died aged 78.

Spencer Johnson, whose book Who Moved My Cheese sold 25 million copies and became a business and self-help phenomenon, has died. He was 78.

Johnson's executive assistant Nancy Casey said on Saturday that he died on Monday of complications from pancreatic cancer in the San Diego-area city of Encinitas.

Johnson was a medical doctor-turned children's book author when he wrote his first hit book, The One Minute Manager, in 1982, with co-author Ken Blanchard.

In 1998 came Who Moved My Cheese, a slim fable on embracing change based on a story Johnson had told friends and used in speeches.

The book featured two mice and two tiny humans in search of food, and showed how humans' stubbornness holds them back.

The book became a constant in graduation addresses and motivational seminars, and spawned teen and kids' editions.