Updated Saturday, November 24, 2012 at 01:23 PM
Three years ago, Andrea Sanders was training for the 2009 Seattle Marathon.
She had just run the Rock 'n' Roll half marathon that summer, and it was her goal to run a full marathon before her 40th birthday.
Months of extensive running and preparation had her ready for the 26.2-mile run, but just weeks before she turned 40, she found a lump in her breast.
Sanders was diagnosed with breast cancer, and the rigor of running a marathon, her doctors said, wouldn't be the best thing for her body. She was scheduled to have her first surgery two days after the 2009 Seattle Marathon.
Not knowing if she would have the opportunity again, Sanders made the decision to run her own marathon, which she called the Sanders Marathon. She mapped out a course similar to that of the Seattle Marathon and ran her 26.2 miles about two weeks before the Seattle Marathon and two days before she turned 40.
Her husband drove alongside, giving her water and encouragement. The rest of Sanders' family waited at the finish line.
"I spent so much time training and being away from my family, so I said, 'You know what? I don't know what the future holds for me. I'm going to run this race for myself,' " Sanders said.
It also prepared her for battling cancer.
"I feel like I did really, really well through all that and I think it's because I was in the best shape of my life," Sanders said of her treatment. "It really prepped my body and my resolve (knowing) that I can get through this, I ran a marathon."
Sanders rode in the pace car at the 2009 Seattle Marathon, which her brother was still running in. But it just wasn't the same as being able to run in it, she recalled.
"It was definitely bittersweet," Sanders said. "Just standing at the finish line and watching all those people meet their goals, and I wasn't able to."
Two days later, she went in for bilateral mastectomy surgery.
Once Sanders started chemotherapy, she wasn't able to run. She turned to yoga to fill the void, but couldn't wait to be able to run again.
Six rounds of chemotherapy and countless surgeries later, Sanders is ready and able to do the marathon she intended to run in 2009.
She has been training for this year's Seattle Marathon, which is Sunday, since early July. The only difference in this year and 2009 is that she now has the experience of conquering something much greater than 26 miles.
Running on Sunday means much more than it would have in 2009, not just for Sanders, but also for her biggest cheerleaders — her two daughters.
"I'm happy to be a role model for them," she said. "To see mom have this big hurdle in her life and to be able to conquer it and get back to things in my life that I love, and one of them is running, is great."
This year, Sanders won't be in the pace car watching others cross the finish line. And she knows that will stir up some feelings that she's held on to since her diagnosis and inability to run three years ago.
"I have no idea what kind of emotions I'll have," she said. "I'll probably be so sweaty and maybe it'll be rainy so maybe nobody will know if I'm crying. But I think elation is the emotion that I hope to have."
Sanders and the others running the full marathon will start at 8:15 a.m. Sunday on Fifth Avenue between Harrison and Mercer streets.
Seattle Marathon at a glance
When: Sunday, marathon walk starts at 7:15 a.m., half marathon starts at 7:30 a.m., half marathon walk starts at 7:45 a.m., full marathon run starts at 8:15 a.m.
Start: 5th Avenue between Harrison and Mercer Streets, east of the EMP.
Course: Rolling course with hilly sections and scenic views of downtown Seattle and Lake Washington. Finish at Seattle Center. The full marathon crosses the I-90 floating bridge.