A Texas woman, pregnant with her second child, is facing an uphill battle as she deals with colon cancer.

Tyisha Kemp, a 27-year-old from San Antonio, was diagnosed with stage 4 colorectal cancer 22 weeks into her term, a condition that pregnant women have a one-in-13,000 chance of contracting.

Nevertheless, she is determined to beat the odds and is eagerly looking forward to the birth of her son. She already has a 3-year-old daughter.

"He's growing fine. His heart rate is amazing," Kemp told KSAT. "He's ahead of the growth curve," she said, with a smile on her face and her hands on her stomach.

Twenty-two weeks into her pregnancy, Kemp said she had nausea and vomiting. Concerned, she went to the hospital. She was diagnosed with cancer; like similar cases, the cancer symptoms had been confused with pregnancy symptoms, KSAT reported.

"I heard it. I cried about it," Kemp told KSAT. "You think about what it means. And for me, I go into 'What do we need to do?'"

With a 3-year-old daughter and a son on the way, Kemp said she has no choice but to be a warrior. Her situation is so rare that doctors have only documented about 275 cases, and each is different.

"She's not a candidate for surgery because of her pregnancy, so her only option is chemotherapy," Kemp's oncologist, Dr. Ed Hesita, told KSAT.

Hesita is a doctor with Texas Oncology, a network of comprehensive cancer care centers throughout the state.

Every two weeks, Kemp starts a 24-hour chemo treatment. Tests show the baby hasn't been negatively affected, but Hesita told KSAT that Kemp needs more aggressive chemo very soon.

"We're trying to figure out whether or not to deliver early or go more aggressive while pregnant," Kemp said.

"I went from possibly having to terminate, to maybe deliver at 24 weeks, to now. I'm at 32 weeks pregnant still doing my treatment," Kemp said.

Kemp's family has set up a GoFundMe page to help pay for medical costs.  As of Saturday morning $3,875 of the family's $25,000 goal had been raised.