The complete cancellation comes after the 67-year-old singer was forced to call off several recent shows due to health concerns, reported Entertainment Weekly.
"I'm getting the best medical care and we are all extremely optimistic. I will fight through this like I've fought through the many other obstacles in my life. Thank you all for understanding," Bradley said in a statement.
"Music is how I share my love with the world, and the love that my fans have given back brings me so much joy. I look forward to seeing your gorgeous faces soon, and to continue to share my love through music," he said.
He had already spent much of 2016 on the road in support of his third album, Changes, which was released in April.