The chemistry behind cancer

As I am starting the next phase of chemo treatments and have new biopsy reports back it is a great time to clarify some of the logic behind this crazy cancer care.

When I was diagnosed with breast cancer originally back in 2006 I was very young, only 30 years old.  I had 3 children, the first was born before I turned 26 and I breastfed all 3 children – so, in spite of having children and breastfeeding (two factors that decrease likelihood of breast cancer) I still got it, and very young.

While doctors can get a pretty good idea of whether you have cancer or not, positive confirmation is done through analysis of cells.  So, the biopsy is the definitive determination of whether you have cancer and what type of cancer you have.  Additionally, they test breast cancer cells to understand which elements may be feeding the cancer growth.  Three key elements are tested.  The first 2 test the amount of hormones, estrogen and progesterone, present in the cancer.  The outcome is referred to as being estrogen or progesterone positive or negative.  Positive = the cancer feeds off of that hormone.  The third element test for a protein called human epidermal growth factor receptor 2 (HER2), which promotes the growth of cancer cells.  Again, positive means that the cancer feeds on this protein. About 1 of every 5 breast cancers has a gene mutation that makes an excess of the HER2 protein. HER2-positive breast cancers tend to be more aggressive than other types of breast cancer. (mayoclinic.org)

So, you may hear about a breast cancer that is triple positive, triple negative, hormone negative and Her 2 positive or hormone positive and HER2 negative.  My cancer was triple positive – estrogen, progesterone and HER2 all assisted in the growth of my cancer.  This is a very aggressive form of breast cancer and, until targeted HER2 therapies were developed, was very deadly.  With the discovery of Herceptin in 2006 for non-metastatic breast cancer and now Perjeta which was FDA approved in Nov. 2014, the prognosis is significantly better.

Wanna geek out? See the Herceptin timeline here. See the timeline of other Genentech drugs, including Perjeta here.

In 2011 when I was diagnosed with metastatic breast cancer the cancer had spread to my spine and sternum.  A biopsy was done, which confirmed that the cancer cells originated from breast cancer.  So, while the cancer was making a home on the bones, it is still breast cancer.  This is true of any metastatic cancer.  It is still the cancer of the original site, whether breast, skin, colon, lung etc.  But, it has spread to a distant site, which is what makes it metastatic. 

The 2011 biopsy of my spine showed the tumor to be hormone positive by HER2 negative.  So, the treatment I had previously for the HER2 protein was effective. 

In 2014 I had a lymph node in my stomach with cancer activity.  That biopsy revealed the cancer was again triple positive, so we added the Herceptin and Perjeta back into the regimen.

My most recent new cancer growth, a lesion on the liver, has been biopsied and shows to be hormone positive and the first test (a stain) showed it as HER2 negative.  A stain test is very subjective because a lab employee is comparing the amount of staining in the specimen to a known positive cell. What one diagnostician may say is a 2+ another may call a 3+.  Therefore, another sample is sent to a central lab for a FISH test.  The FISH test is objective because the diagnostician counts the number of HER2 receptors on the cell.  The FISH test came back saying the tumor is triple positive.

So what does all of that mean?  Well, we know the chemo I have been taking – taxol – is no longer effectively controlling the cancer because tumors have started to grown in the liver.  We also know that the HER2 treatments are ineffective because that protein has not been suppressed in this new growth. 

Last Thursday I began a treatment called Kadcyla/DM1.  Kadcyla was approved in March 2013 for use in metastatic breast cancer treatment. See press release here.

In my opinion, it is good that the liver lesion presented.  The liver lesion gave us soft tissue for a biopsy which tells us about the chemical make of the new tumors in my body.  This makes the choice of drugs based in science, not a best guess.   With the tissue sample we are also hoping to get genomic testing of the tumor done. What is genomic testing? Well, it is looking at the DNA of the cancer cells and determining which part of the DNA is damaged.  It answers questions such as which chemo agents will work best on a subtype of cancer, other therapies that could be effective, etc.  Hopefully over time these tests will become more advanced and will provide even more information.

All of life is a series of chemical and biological reactions.  Cancer is just one of these reactions that went wrong and then reproduced incorrectly out of control and creating a mass of damaged cells in someone’s body.  Understanding the science of cancer is the first step in choosing smart treatments.  I am hoping other chemical reactions will help me to control/master the cancer in my body.  I believe that complimentary medicine, treatment offered along with the western medicine I receive, could help my body fight the cancer growth.  At least, it will make me feel good about what I am doing for myself.  So, one complimentary treatment I am choosing to add is nutrition. 

Kadcyla has the side effect of losing your appetite and this is all the more reason to be thoughtful about what I am putting into my body.  One change is buying organic produce according to the Dirty Dozen, Clean Fifteen theory.  Also, I am realizing how hard it is to get adequate protien – again the lack of appetite. (Guidelines on protein consumption) But, one thing that I have started, and enjoy a lot, is juicing.  Did you know you can juice cabbage?  Did you know broccoli juice is bitter?  I am increasing my fruits and veggies and like what I feel like when drinking fresh juices. 

So, that’s the long update.