R&B Singer Nivea Reveals Leukemia Diagnosis

R&B singer Nivea is battling leukemia ... and she says the diagnosis has changed how she looks at life, even as her treatment continues to go great.

The "Don't Mess with My Man" singer opened up about her cancer battle during a recent sit-down on the musical interview series "Cadillac Chronicles" ... saying she learned she had leukemia earlier this year and is grateful to God for her progress so far.

Nivea says the experience has put plenty into perspective ... reminding her how suddenly life can change and pushing her to seize every opportunity that comes her way.

The 44-year-old says she's now doing the things she has always wanted to do ... diving back into music and going to school for audio engineering, with hopes of learning how to mix her own records.

Nivea is also focusing on her four children ... three of whom she shares with ex-husband and R&B singer The-Dream. The pair married in 2004, welcomed daughter Navy and twin sons London and Christian, and separated in 2007.

Before that marriage, Nivea dated Lil Wayne and became engaged to the rapper in 2002 ... though Wayne called it off the following year. The former couple later reconciled after her split from The-Dream and welcomed son Neal Carter in 2009.

Neal -- Wayne and Nivea's only child together -- has since begun making music under the name Lil Novi.