Tionne “T-Boz” Watkins revealed that she has been waging a secret battle against a brain tumor that was diagnosed in 2006.

In the Oct. 12 edition of People magazine, the 39-year-old said that she underwent a seven-hour surgical procedure back in 2006, during which doctors peeled the tumor from her brain stem by making a cut behind her ear.

The divorced single mother of one said she was battling the tumor earlier this year during filming of NBC’s Celebrity Apprentice, but didn’t want to make it known to the public. “I didn’t want pity. I was there to help sick children,” she told People.

T-Boz, who also suffers from the blood disorder sickle cell anemia, competed on Donald Trump’s reality series to raise funds for the Sickle Cell Foundation of Georgia.

She said people are “shocked” when she tells them the news, but added, “I won’t let you feel sorry for me.”