Breast cancer diagnosis upends lives of younger women navigating motherhood

Jenna Tomasiewicz was 28 weeks pregnant with her second son when she noticed something that brought her to her doctor's office.

"I was putting on lotion and I found a lump on my right breast," Tomasiewicz said.

At 34, she was diagnosed with stage 2 breast cancer that had spread to the lymph nodes in her armpit.

"I was like the epitome of health. I was so fit. I was always eating so healthy. I have no family history of breast cancer. I even tested negative for the BRCA gene. So cancer wasn't even on my radar," she said.

Doctors recommended that Tomasiewicz begin chemotherapy while pregnant. She went for a second opinion and she was told it would be safe.

"I was induced at 37 weeks and, gosh, it was just the most blissful moment of my life when he was born," she said.

Her husband, John Tomasiewicz, recalled the uncertainty of that time.

"We were just starting our family, just starting our life together. So it was very difficult," he said.

For Margot Casino, learning she carried a BRCA mutation through a 23andMe test prompted a series of difficult decisions. The mutation put her at a much higher risk of breast cancer, and she risked passing the gene to their children.

"My husband and I at the time decided to do IVF to ensure that our children didn't inherit this mutation and wouldn't have to face the same difficult choices that I faced, and am still facing today," Casino said.

She also underwent preventive surgeries, including a double mastectomy and hysterectomy, in an effort to reduce her cancer risk.

"I thought that I had some sort of leg up in this metaphorical race against cancer, essentially. And it really felt like someone pulled the rug out from under me," she said.

While recovering from one of the surgeries, Casino felt a lump. A week later, she found another. Her doctor urged her to undergo an ultrasound and biopsy.

"That confirmed the diagnosis of stage 3C invasive ductal carcinoma. In eight weeks, it had grown and spread through my axillary lymph nodes into my internal mammary nodes," Casino said.

According to the American Cancer Society, about 1 in 10 women diagnosed with breast cancer is younger than 45.

This Breast Cancer Awareness Month, Casino says she has reached a milestone in her treatment.

"I feel great. I was told that there is no evidence of disease at this time on the one-year anniversary of my diagnosis," she said.

Tomasiewicz is now a social worker and cancer coach. Her son is healthy, and she is in remission.

"Having cancer didn't matter. I was in a lot of pain, that didn't matter. I was bald, that didn't matter. Like nothing in the world mattered," she said.

Both women are involved with the Susan G. Komen Foundation, raising awareness and supporting funding for advances in breast cancer treatment.

CBS News New York is partnering with the Komen Foundation for this year's Race for the Cure, taking place Saturday.

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