One of the friends who comes to our dramatic Thanksgiving dinner, Peter, is a biologist who used to work at Genentech, the California biotech company that developed the monoclonal antibody, Herceptin, that is part of my chemo regimen. Actually, monoclonal antibodies are not exactly “chemo,” but never mind.
Peter says that at one point, Genentech scientists attached some sort of marker to chemo drugs so that they could see how the drugs traveled through the body. He says when you watch a video of this, the drug comes in through the IV, then is shunted quickly to the heart. Then, pump-pump-pump, the heart pushes the chemo out and it billows out to every artery and vein in your body. And then, almost as quickly, most of it gets shunted into the bladder. Aha! So that’s why I’m always rushing to the bathroom with my IV pole about halfway through a four-hour chemo infusion.
So, how does the chemo work if it’s in the body such a short time? Well, it turns out it’s kind of like a drive-by shooting, or a sleeper computer virus. Most chemo drugs mess with the DNA of cells. So the chemo passes by most of the cells in your body over the course of an hour or two, throwing a molecular wrench into a cellular structure that’s key to cell division. The old-line platinum drugs, like the Carboplatin I’m taking, damage “micro-tubules” that are key to RNA. RNA, in turn, is key to pulling chromosomes apart so that they can make copies of themselves to be used in newly-divided cells.
The damaged microtubules set off a crisis in the targeted cells. They try to divide, and try to divide. After seven to ten days of this, the cells give up. If they can’t divide, they die. That’s when your hair falls out, and that’s also when you have the lowest white blood cell count, the “nadir” at which you have to be most careful about washing your hands and avoiding direct contact with toddlers and public bathrooms. It’s when even a mild temperature, say 101F, is a go-straight-to-the-ER ticket.
I love this image of chemo as a hit-and-run. I’m reluctant to say that it’s a “fun” idea, because little about cancer is a laugh riot. I’m writing this two days after a chemo infusion and I feel like my head is full of cement. My stomach is doing back flips, I have a headache and no energy. I have no idea how I will ever get ready for Christmas or unpack the last of the moving boxes. But this new way to understand chemo makes me smile. Take that, cancer cells!