Good Drip

All done with my second round of chemo. This week I got the whole "cocktail". It went fine, it was a lot quicker than last time (they were less worried about allergic reactions). I was home in less than four hours. I managed to talk them out of the Benedryl this time (I didn't need a crazy nap today!). Some minor side effects from the chemo are creeping in already. My tongue is tingly and things don't taste right. Otherwise I feel fine. I even snuck in a run to Target and Fourth Street! I'm a little less worried this time through because I have a clue about what to expect (yes, it might change, but it isn't a complete unknown).

Warning: I'm going to geek out on the chemicals now. I'm a science teacher (who's not teaching today) so I figure I'm allowed. Stop reading now if you have no interest in how the chemo thing works. Here comes the nerdiness...

I start off my cocktail with premeds of Dexamethasone (steroid) and Emend (miracle anti-nausea stuff). These things are supposed to keep the serious side effects at bay. The next up is an hour long drip of Taxotere. Taxotere was first made from the needles of European Yew trees (now it is synthesized in labs). Taxotere works by binding to microtubules and making it impossible for cells to divide. Taxotere and Taxol are both classified as taxanes (Taxol is the "mother" of all taxanes). Taxol was first discovered back in the 1960's after the National Cancer Institute got together with botanists from the USDA to start screening plants in search of compounds that killed cancer cells. It took about 30 years from its discovery in the 1960's before it was approved in the 1990's (holy cow!). Originally Taxol was derived from the bark of the Pacific Yew. Its use as a chemotherapy drug lead to the harvesting of lots of Pacific Yews (it takes a lot of bark to isolate enough Taxol for a chemo drip!). Not only were Pacific Yews not the most common tree to start with, but they grow in forests where you find spotted owls (a threatened species). This was a problem for the first couple years of use, but by 1995 a method for synthesis of taxol in the lab had been developed and the controversy (helping cancer patients vs. saving the forests and the birds) was over.

The Taxotere is followed by a 1/2 hour drip of Carboplatin (yes, I now have some platinum coursing through my veins). Carboplatin is an alkylating agent. It reacts with my DNA and adds alkyl groups (methyl, ethyl etc). Essentially it causes mutations that will hopefully kill the cell. Like all chemotherapy drugs, neither Taxotere nor Carboplatin can tell the difference between cancerous and non-cancerous cells, so it is killing any cell that is undergoing mitosis. Since cancer cells do this so often, they are killed (hopefully), but there are some civilian casualties as well (hair follicles for one thing- my hair is now starting to come out).

I finish up with Herceptin dripped in over a 1/2 hour or so. I go every week for Herceptin and technically that isn't chemo- it is a targeted therapy that works specifically on the cancerous cells and has very few side effects. My cancer cells have an abundance of HER2 receptors sticking out of their cell membranes. This receptor sends messages to regulate cell division, but in cancer cells like mine the HER2 receptors just keep sending the message to divide the cell. This is no good, it makes tumors! Herceptin binds to the HER2 receptors and stops them from sending out the "divide" message. Once it has bound to the HER2 receptors, my immune system (which according to my blood work is doing fine!) gets rid of the cancer cells. Herceptin (a.k.a. trastuzamab) is a wonder drug for HER2+ folks like me.

Once the Herceptin drips through, they flush my port. The weirdest part of this is that I don't really notice the taste or smell of any of the chemo drugs or the Herceptin, but when they flush my port with saline and Heparin (to keep any clots from forming in it) I can taste both. Saline (which should taste like salt water) tastes very chemically and Heparin tastes like fake citrus flavor, weird. The only explanation I can think of is that they really push that stuff in fast with a syringe (no drip drip here at all!). Anyway, once all that is done, they put a bandage on and I'm outta there.

In related news...there is a "super herceptin" (TDM1) drug that is currently in stage 3 trials that sounds very promising. It combines Herceptin (which binds to the HER2 receptors that my cancer cells have an abundance of) with DM1, a chemotherapy agent. This would get chemotherapy straight to the cancer cells rather than spreading it throughout the body. Who knows when or if I'll ever need this drug, but its existence gives me one more option in the fight!!

Just to give credit where credit is due, the info here came from: my doctors (mostly Dr. Z my breast surgeon), carboplatin.org, taxotere.com, the numerous pamphlets I have been handed by my nurses and The Story of Taxol: Nature and Politics in the Pursuit of an Anti-cancer Drug By Jordan Goodman, Vivien Walsh (the preview on Google).