Mom finishes Chicago Marathon after training helped reveal breast cancer diagnosis

CHICAGO (WLS) -- Erika Aleman ran the Chicago Marathon on Sunday after undergoing chemotherapy while training for the race. This Friday, she'll undergo life-saving breast cancer surgery.

Aleman said she started training for marathons in 2015 and fell in love with running.

"It helped me a lot with my mental health," she said. "Any time I have any struggles, just go for a run and everything after that seems easier."

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Aleman ran in the Chicago Marathon on Sunday, completing it in 6 hours and 7 minutes. It was her slowest time compared to previous years, but she says it was her most important race.

"The goal was to finish," said said. "I didn't care if it would take me 7, 8, 9 hours."

The 43-year-old was diagnosed with an aggressive form of breast cancer back in March. She found a lump after losing weight while training for last year's marathon.

Fearful she didn't have long to live, Aleman met with Dr. Regina Stein, an oncologist at the Lurie Cancer Center at Northwestern Medicine, who treated her with chemotherapy and immunotherapy.

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"This breaks the bond between the immune cell and the tumor cell," Dr. Stein said. "The immune cell suddenly is awoke and realizes that can't be here and goes on the attack."

All the while, Aleman trained for the marathon while relying on the support of her daughters, her running group and other women with cancer.

"I met so many ladies and I promised them that I was going to put their names on my flag, and I was gonna cross the finish line," she said.

This Friday, Aleman will undergo a bilateral mastectomy. She said she's already planning for next year's marathon, hoping to run fast enough to qualify for Boston.