So far, today has been a really productive day. I got my 17-month-old son up and dressed and fed, the house cleaned for the realtor's open house and got myself all prettied up for a date with my husband later today. This will be a good day. The sun is out, the leaves are changing and now my son is playing in his crib so I can enjoy my cup of coffee in peace. That cloud overhead--that is my stage 4 breast cancer diagnosis, and it is not ruining this day, nor will I let it ruin the days ahead. That has been my motto ever since my mother died in May of this year, and I was re-diagnosed with bone metastases at age 30. Life is short, so live it with passion. I am pretty much a totally normal, stay-at-home mom; I take my son on lots of play dates, pretend to plan his wedding with a girlfriend's daughter, play with our dog outside and meet up with my husband on date night. It's a wonderful life. In addition, we are planning for our future; we are in the process of building a house and selling our current duplex--a dream that I had put off for years.If it wasn't for seeing my oncologist every month, I think I could totally forget I even have cancer. Although I do have days where it clouds over with worry of progression and failing therapies, and I fall apart entirely. Friday was one of those days. After a great five months on oral chemotherapy, my tumor markers suggested it was time to look to the next treatment plan. So after the storm of my emotion settled, I can once again poise myself for another battle as I await the PET scan results.The cancer has definitely changed my life, but it has not been all bad. Prior to discovering a lump while breast feeding, I was planning my career in science. I was expecting to graduate with my PhD in immunology and go on to hopefully study cancer immunotherapy. While the former came true, and I will be graduating in December with my PhD, the latter is not exactly what I had in mind.On closer examination, I am actually still doing what I'd planned, only from a very different perspective--the patient's perspective. Rather than designing the experiment behind a bench, I am the experiment. I am the unknown, and I know there are 1000s of scientists standing behind their research benches hoping and praying that their hypotheses are supported and remission is headed my way.To all those researchers out there, I say thank you and don't be discouraged. Science is a collective process, and it takes many, many incremental steps to take basic science to the bedside. Granted, I wish I weren't the guinea pig, but this is the hand God dealt me and I need to play it as best as I can. Choosing to stay home with my son instead of continuing into a post-doctoral fellowship was not part of my plan, but I love it more than anything else in the world--so for that, I say thank you, cancer.Kristin Ness-Schwickerath is a stay-at-home mom to her son, Parker, and a cancer survivor. Prior to staying home, Kristin was a graduate student at the University of Iowa working on her PhD in immunology. She will graduate in December 2012. She blogs at kristin-notdying-blog.blogspot.com. "I may be fighting metastatic breast cancer, but I am optimistic for a long life."