The rocker went public with news of his lymphoma diagnosis earlier this year (12) and the band was forced to change its tour plans to give him time to recover.
However, Iommi refused to give up work completely and continued recording the band's new album while he was undergoing chemotherapy. He has now revealed he also went back to his book and wrote a slew of new chapters to give fans an insight into his health scare.
Iommi says, "It's got new chapters bringing everything up to date, including my battle with lymphoma."
The book, titled Iron Man: My Journey Through Heaven and Hell With Black Sabbath, was released in the U.S. this month (Dec12).