Astro-what?

I first heard the term Astrocytoma when a nurse called me the week following my surgery in which they took a sample of brain tissue for a biopsy. At the time of the call they were able to confirm that we were dealing with a Grade 2 Astrocytoma. What we didn’t know at that time was whether it was cancer or not, so they sent my tissue sample to the Mayo for some final testing. For those that have read my prior blog posts, An Introduction to Kiss My Astrocytoma & Digesting the Diagnosis, you already know what the outcome of that testing was. I learned on June 23rd that I have brain cancer, and more specifically, a cancerous Grade 2 Astrocytoma, IDH1-mutant. Over the course of the next few weeks I was able to learn what all of that meant. I’ve been able to familiarize myself with all the medical terminology that’s been thrown my way and I hope to help break it down for those of you who are interested to learn more.

Grade 2 Astrocytoma

Also called a low grade astrocytoma or a diffuse astrocytoma, I have learned that a grade 2 astrocytoma is considered to be an infiltrative tumor. Infiltrative tumors grow among and within the existing brain cells. These tumor cells don’t grow as an additional mass on the brain, rather they grow laced within the healthy cells. The primary characteristics of this type of tumor include slow growth, not having well defined borders, and most often occurring for adults between the ages of 20 and 40.

The cause of these tumors is highly unknown – there isn’t a genetic component and the only thing they can say for certain (along with most cancers) is that prior radiation exposure is a risk factor. Astrocytes are supportive cells for the brain in the nervous system. Because the tumor stems from these astrocytes in the nervous system, this explains the various neurological symptoms I’ve experienced on both sides of my body. My brain knows something foreign is there so my nerves are susceptible to misfiring which can lead to the concerns I’ve seen with balance, vision, speech, perception, tingling sensations, tremors, etc.

Tumor Location

I have mentioned in previous blog posts that I have 3 lesions on my brain, and yet I’ve been saying that I have 1 brain tumor. While the 3 lesions on my brain appear in the MRIs to be separate occurrences, we can assume they are connected to the same condition that has spread. That being said, I am dealing with a multifocal brain tumor, meaning it is 1 brain tumor that appears in multiple spots. All 3 lesions are in the right frontal lobe of my brain, but they are in very different locations of my right frontal lobe.

The 2 smaller lesions are located in the posterior superior frontal gyrus and the anterior right superior frontal gyrus. They would have been able to successfully resect the tumor located in these 2 areas. The bigger lesion located in the superior medial precentral gyrus was the area of concern. This lesion is located along what is called the motor cortex which is a strip of the brain that controls movement of the body. Resecting the tumor in that area very likely could have left me paralyzed on the left side of my body. This is the lesion they targeted for the biopsy, so I am actually able to pinpoint where that is located by looking at the scar on my head from the surgical incision where they had to drill the burr hole.

Surgery

Because of the infiltrative nature of this tumor and the ill-defined borders, surgery is tricky with astrocytoma tumors as removing tumor cells in these cases inevitably means damaging healthy tissue along the way. Surgery for brain tumor removal is referred to as resection, with the primary goal to remove or resect as much of the tumor as they possibly can. Best practice is to only perform a surgery of this nature if they know they are able to resect a vast majority of the tumor considering this type of surgery is a craniotomy. In my case, due to the location of the tumor they would not have been able to resect a large enough amount of the tumor in order for the benefits to outweigh the risks.

Although they would have been able to resect 2 of the 3 tumor areas, the percentage of resected tumor would still not have been high enough to make the surgery worth it due to not being able to touch the bigger lesion along the motor cortex. A couple of different surgeons were consulted to ensure it wasn’t just a surgeon comfort/preference thing (one from the Mayo and one from Abbott), and both surgeons agreed that this is not a surgery they would perform. Believe it or not, I was pretty bummed about this. While I wasn’t necessarily excited at the thought of a craniotomy (it was hard enough going through the surgery for the biopsy!), I knew that if surgery was an option for me, that would be less residual tumor that we would have to target with radiation. With surgery being off the table, I knew that meant we had to target 100% of the tumor with radiation which was a much bigger deal.

IDH1 Mutation

My full diagnosis is a CNS WHO Grade 2 Astrocytoma, IDH mutant. CNS WHO stands for Central Nervous System World Health Organization. The IDH1 gene is essentially a protein coding gene. It provides instructions to make an enzyme called isocitrate dehydrogenase. All we need to know about this gene is that I have the mutation and that it’s a good thing. This mutation has proven to have a more favorable prognosis and higher survival rate with completion of chemotherapy and radiation. Overall it is known that patients with the IDH1 mutation respond to treatment better overall. Finally, some good news!

How Radiation Works

Unfortunately, even though I’ve completed my course of radiation treatments, my tumor is not going anywhere anytime soon. I will be getting regular MRIs going forward but we don’t expect to see any changes quickly.

Radiation damages cells – both tumor cells and healthy cells. The idea behind doing radiation treatments every day throughout treatment is that the healthy cells can recover within 24 hours of the damage, just in time for the next day’s treatment. The tumor cells however will eventually not be able to keep recovering prior to the next treatment. After 6-7 weeks of this cycle, the tumor cells will be defeated.

The tumor cells do not actually die off until they attempt to divide. Division is the most complicated thing a cell can ever do. The way tumor cells spread is that they divide out of control. Radiation damages the genetic make-up of the tumor cells. Now when the cells attempt to divide, they will die instead. Therefore, the tumor cells will die at the same rate that they would have spread. And because I have a slow growing brain tumor, it will also be a slow dying brain tumor.

Next Steps

The next step in my treatment plan will be starting an oral chemotherapy pill called Temodar. I expect to start this mid-to-late October. Each month I will take it for 5 consecutive days and then take the rest of the month off. I will do this for 6-12 months. I have a lot to learn yet about oral chemotherapy but I have been assured that this drug is pretty well tolerated. As I learn more, I’ll share more! To learn more about my condition, I highly recommend checking out the National Organization for Rare Diseases.

Coming Up on Kiss My Astrocytoma

Hailey’s Toolbox: Coping 101

A Day in the Life

A Letter to my Pops

A Letter to my Mom

♡ Hailey

Questions? Comments? Ideas?