Treatment by the Numbers

Math is my comfort zone, though the calculations are not always comforting. I understand math and statistics. They give me a more concrete hold on the treatment decisions that can feel like gambling with my future. I trust the medical expertise of my doctors, and the numbers help me understand where their recommendations are coming from. It helps it all seem less random.

I was diagnosed with breast cancer at 43, an age when my personal risk was calculated at only 6%. As I teach my statistics students, a risk of 6% does not make an occurrence unusual. But it sure seems like it when it happens to you! My diagnosis has dramatically raised the risk of diagnosis before 50 for my sister and daughters. They will need to be vigilant. My one comfort is that my diagnosis will provide them with opportunities for better, more aggressive preventative care and screening. My hope is that they can lower their own risk, and be diagnosed earlier than I was if they do develop cancer.

Now that I’ve been diagnosed, I have a 10-12% risk of local or regional recurrence in the next 10 years (that does not include my risk of distant recurrence), so I need radiation to reduce that. SO MUCH MATH in radiation. First is the amount. A total dose of radiation is calculated, to be spread out over many visits. Originally this was going to be 33 daily visits, but my new radiation oncologist is thinking 25. Research is showing that spreading it over less visits, with more each time, has better outcomes. Then there is the placement of the beam(s). They will use a CT scan to create a model of my chest and armpits, with me positioned as I will be during radiation. The doctor will use this to determine the best angles and how many beams are necessary. The goal is to deliver the necessary dose to all the right areas without the beam passing through areas that don’t need it (especially avoiding vital organs like the heart and lungs), and without over-frying the skin in any one location. Ah, the trigonometry problem that creates!

Through treatment and recovery, there are many things that must be measured and monitored. The icky-feeling side effects of my new chemo are mild, thank goodness. The more insidious side effects, including damage to vital organs like my heart and liver, must be continually monitored. All kinds of bloodwork numbers, as well as heart function numbers (how hard it expels blood and how much the left ventricle contracts when it pumps). There are also range of motion measurements. My occupational therapist keeps track of how much I can move my arms, comparing the angles to my pre-surgery numbers. I can’t get my arms straight above my head like before yet, but I’m doing all my prescribed stretching and I’m close.

There are so many unknowns, which can be unsettling. But these numbers help me understand my treatment plan and monitor my progress as we blast the cancer to bits.