Friday, June 27, 2014

VMAT

Hello all.  Chris here, to fill everyone in on the details we know and what the plan moving forward is.

First, the final pathology has come back on the Tumor in Ann's neck and its a mixed bag.  One the positive side the tissue described to me as a "hamburger patty of tumor" that wrapped around Ann's neck from chin to almost the occipital bulge (aka back of the head) was in fact partially necrotic adipose (aka fat) tissue.  Why partially necrotic?  Beats me, and almost everyone else we have talked to about it.  But it explains why it didn't show up on a PET scan, which only show things with a high metabolic activity.  Necrotic or dying tissue has almost no metabolic activity.  So that mystery is solved.

The bad news is that within this mass was in fact Squamous cell metastasis.  Fun fact Metastasis is taken from greek (more about that in another post) Meta - meaning New and Stasis - meaning Place. Anyway, this mass of adipose tissue was masking the presence and growth of the cancer in Ann lymph nodes.  The cancer was present in ten lymph nodes from level IIB around the C2 vertebrae all the way down to level V around the adams apple.  Which is why the planned surgery took 5+ hours, and not the planned 2.

 All together the official diagnosis is a Metachronos (new-time) TxN2bM0 or Stage Iva recurrence.  Tx - unknown primary tumor.  N2b - more than 1 lymph node involved on the same side of the neck.  M0 - no present distant metastasis present. This all sounds depressingly bad, but we have been assured that it does get worse.   So while it may feel like we didn't catch this as quickly as it could have been, our new Radiation and Chemo Doctors are pretty confident about the prognosis for successful treatment being about 80%.

Both have pointed out that Ann didn't have the truly critical factors of disease being present on the opposite side of the neck, or it being involved on the glottis or base of the tongue.   Plus they have put together a very comprehensive plan to tackle this.

What they plan to do is use a Truebeam VMAT machine to irradiate both sides of Ann's neck (right is necessary, the left because we want to be super aggressive with treatment).  VMAT stands for Volumetric Modulated Arc Therapy, and it is a variation of IMRT, or Intensity  Modulated Radio Therapy.  VMAT machines allow Doctor's to treat a variable volume of tissue, while sparing critical tissue.  In my sweet heart's case, the tissue targeted will be everything from the jawline down to the collar bone, with the spared  tissue being the spinal cord only.

The machine will deliver 66 Gy.  A Gy is a SI unit for radiation known as a Gray, which represents the the energy delivered to a mass of tissue.  So its fundamental units are 1 Joule/Kilogram or 1 m^2/s^2.  The technically savvy among the audience will notice that a Gray (Gy) and a Sievert (Sv) have the same SI measurements, which makes them interchangeable units.  The only difference is that a Gy is spoken of in terms of emission and a Sv is spoken of in terms of absorption.  An important distinction  in some occupations - NASA for example will not allow an Astronaut  to accumulate more than 1 Sv in a lifetime.  And each time you eat a Banana you absorb 0.098X10-6 Sv.  Funny to think that you have a finite number of Bananas you can expose yourself too at one sitting before endangering yourself to cancer or radiation sickness.

In Radio Therapy treatments however the aim is for the source emission and dose absorbed to be as close to equal as possible.  So Ann will be accumulating 66 times the maximum lifetime dose of an Astronaut.  Which is about 132 trips to Mars and back.  MD Anderson has pointed out that the standard of care is only about 53 Gy, but they are pushing hard to make sure we don't ever have to deal with this particular gremlin ever again.

On top of this they are adding a chemo agent called Cisplatin.  Which has been described to us as "a little bit of chemo", in comparison to what we have been through already for treatment of Leukemia and 2 BMTs.  The purpose of the chemo agent is to head off any metastatic disease that may be out side of the field of radiation.

I feel like I am beginning to ramble, so I will leave you guys with a animation the VMAT RT machine , so you can get a better idea of what I've been going on about.  Apologies for the music in advance.





Edit:  Sorry for the typos - I have a terrible habit of trying to dash off a post quickly and then not pausing proof reading it.  It's a habit I thought I had broken myself of, but apparently not.


7 comments:

LPC said...

Please send love to Ann.

Easton Place said...

Sending love to you both.

Ronni Gordon said...

Wow. Probably more than you ever wanted to know but thanks for the update. 80 percent sounds very encouraging.

KathleenRose said...

Keeping FAITH!

Denise said...

Love and healing energy to you Ann. 80 percent - a much better number than I had in my stupid brain - yay! I have nothing to complain about. Bless you both and my thoughts and prayers are with you.

Jody said...

Sending love to both of you. Thank you for this incredibly informative post. Seeing the 80% confidence level in successful treat meant = priceless.

I am here in Houston if I can help in any way and would love to come and visit with you both.

Jody

Nancy said...

Chris, you've become an expert in this field. This is so detailed and although I can't begin to comprehend it all, I know you have! Ann has the very best advocate and caregiver in her corner!!! That's YOU!

I love the 80% prognosis. You guys are amazing and can make this hurdle. Love you both and, as you know, thinking of you constantly.

xoxoxo
Nancy