Terri Mitchell of Santa Rosa, a lifelong swimmer and runner, was shocked when she found a lump on her left breast, a month after she turned 51 in 2010.
"Breast cancer was never on my radar," said Mitchell, who works as a loan consultant for Ryan Mortgage Company in Santa Rosa. "My left breast was sore, and I was sure it was from doing push-ups. But it never went away."
The mother of four hadn't had a mammogram for two years, so she immediately made an appointment. It turned out to be an aggressive form of breast cancer known as HER2. Worse yet, it had already spread to her lymph nodes.
HER2-positive tumors produce too much HER2 protein, making them fast-growing and likely to spread, often to the bones or the brain, through the bloodstream.
At the urging of a colleague, Mitchell went to oncologist Alice Guardino at the Stanford Cancer Center, who enrolled her in a drug trial for Lapatinib, an inhibitor that blocks the HER2 growth-receptor pathway.
"It's an FDA-approved drug, but is typically used with people whose cancer is metastatic (has returned and spread)," she said. "The drug goes across the blood-brain barrier, so it can get into the brain."
After six months of chemotherapy and Lapatinib, Mitchell had a mastectomy on her left breast and took Herceptin for a year. The drug provides a type of antibody that targets the cancer cells and reduces the risk of cancer recurrence.
The good news came after the mastectomy, when she learned that the surgeon had difficulty finding the site of the original tumor. And all her lymph nodes came back negative, or disease-free.
"I really think she saved my life," Mitchell said of her doctor. "She had an aggressive treatment and a drug trial going, and she was forward-thinking."
To celebrate her clean bill of health, Mitchell began training with three friends to complete the Avon Walk for Breast Cancer in Santa Barbara earlier this month.
"For me, it will represent a return to health," she said before the walk. "I feel great, because I'm taking better care of myself."
The four-member team, which raised nearly $10,000 in donations, planned to walk 39miles over the course of two days to help raise money for research and for people who can't afford treatment or screenings such as mammograms.
"Avon uses a lot of the money to provide services to people," she said. "Everybody should be able to get the kind of care I got."
Training alongside Mitchell were two of her Bennett Valley neighbors, Gail Perry and Robin Warren, who mobilized a support team to provide everything from meal delivery to transportation during her treatment.
Because she was part of a drug trial, Mitchell underwent a barrage of tests, including baseline tests and biopsies, throughout the 18-month treatment.
"I had brain MRIs, heart scans, everything," she said. "I was down there two or three times a week for a different scan."
The fourth team member was Libby Hutton, a deputy county counsel with the Sonoma County Counsel's office, who had a brush with breast cancer six years ago, when she was 55.
"Having had it, you really appreciate how prevalent it is," Hutton said. "A lot of the people in our tennis group have had it."