With their new Book of Souls album high on the charts and an ambitious world tour scheduled for 2016, Iron Maiden are as strong as ever — but drummer Nicko McBrain knows that singer Bruce Dickinson's recent cancer scare might have sent the band in a very different direction.

McBrain opened up to Overdrive during a recent interview, admitting that no one in the band knew Dickinson was unwell when they recorded The Book of Souls. "He performed that whole album knowing that something wasn’t quite right with himself – but didn’t get diagnosed till after we’d finished the tracks," he explained. "So The Book of Souls is very special to me and all the rest of the guys. We weren’t aware, and neither was he, that he had the tumor."

Once he realized the severity of the situation, McBrain said he briefly considered the possibility that it could mean the end of the band. "I’d be a liar if I didn’t think for a minute, ‘That’s Iron Maiden finished,'" he admitted. "I thought more about the possibility of losing my friend than anything else, to be honest."

And though McBrain allowed himself a few moments of despair, he says he quickly resolved to trust in his friend's resilience. "I did question his mortality at one point, and thankfully that didn’t last long," he recalled. "I got down on my knees and said a prayer, picked my thoughts up and got positive, thinking to myself, ‘If anyone can beat this, it’s Bruce!’ Basically, I prayed for him and my prayers were answered, as well as everybody else that knows and cares for him."

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