LOS ANGELES (KABC) -- Being diagnosed with breast cancer without a family history is not uncommon.
In fact, the majority of cases occur in women without a family history, but one young breast cancer fighter was told something that was hard to believe.
Rachelle Lee has been documenting her journey on social media to reach other young women, and her videos are meant to be sassy and irreverent.
It's how the beauty and fashion entrepreneur gets people to hear her message.
"I had breast cancer at 29 years old, and it's possible. It's rare, but it's possible, and so I want the world to know that young breast cancer does exist," Lee said.
But this never crossed Lee's mind until 2020.
"I felt some pain and that's when I discovered a lump," she said.
The cancer had spread to her lymph nodes, but what really shocked her was what a genetic test revealed.
Lee tested positive for the breast cancer gene BRCA 2, but no one else in her family did.
"My parents were negative and I was positive. It just didn't make any sense and even the doctors were a little bit stumped," Lee said.
Doctors call it a "de novo mutation".
"It's a spontaneous mutation within the breast cancer gene or genome," said Medical Director of RadNet Dr. Jason McKellop.
He said about a dozen cases have been documented in the medical literature. Having the BRCA 2 mutation puts Lee at an elevated risk of developing another breast cancer or ovarian cancer.
"As high as 85% lifetime risk of developing the disease," McKellop said.
"Seeing that I had the BRCA mutation, to me, it made sense to entirely go with the double mastectomy route," said Lee.
For now, she's holding off on also having her ovaries removed, hoping to have kids someday.
"There was so much more that came with breast cancer than just the treatments itself," she said.
Lee uses her platform to reach other young breast cancer patients. Throughout her treatment, she says getting made up helped lift her spirits.
She started a nonprofit to offer free makeovers to patients and caregivers.
"Now that I'm on the other side, I just ... I seek to bless others and to give back where I can," Lee said.
Besides, being a medical term, "de novo" means start anew and that's what Lee is doing.