The Waterfalls singer will release her memoir, A Sick Life, in September, 2017, and she tells People magazine it will feature candid details about her illness - and the 2002 death of bandmate Lisa 'Left Eye' Lopes.

"I want to hopefully get stuff off my chest and inspire someone at the same time," the 46-year-old says. "A lot of things have happened in my life that will come out in this book that a lot of people don't know about, that I've never talked about. There are a lot of major life changes that I'm so, so, so blessed to have experienced.

"Back in '97, I did a little teaser book - it was called Thoughts - and I told little stories about my life here and there, and the fans really took to it. Now years have passed, a lot has happened in my life, and I think I need another therapy session.

"That book was therapeutic. That's where the songs Unpretty and Dear Lie came from: my poems. And we converted them into songs from that book.

"Back then, I didn't have the brain tumour, and a lot of things have happened in my life that will come out in this book that a lot of people don't know about, that I've never talked about. I really feel like timing is everything, and I'm more mature, I'm wiser, and I have it together a lot more... I think it's the perfect time for me to talk, where I don't feel like I'm going crazy or something."

But T-Boz insists the book won't be all doom and gloom, revealing that doctors once insisted she wouldn't live past 30.

"Then the next death rate they told me was 45 and I exceeded both of those numbers," she smiles. "They told me I would never have kids and my daughter is 16 this year. They told me I would be disabled and I've travelled the world - and I'm still doing it."