Thursday, June 6, 2013

How Do You Spell Relief?

Holy shit. What a day.

This is a very long post. Perhaps the exhaustion you feel reading it will give you a sense of our exhaustion living it.

Today I was scheduled for two scans: a PET scan to check for remote metastasis; and a radiation treatment preparation and planning CT scan. The PET scan required a 6-hour fast and the CT scan, which was only two hours later, required a 4-hour fast. So no food since last night.

Although come to think of it I was awake from 3:00 - 5:00 AM being terrified. I could have eaten then!

Little Tech Talk here:

PET is an abbreviation for Positron Emission Tomography. It is a type of medical scan in which a radioactive (positron-emitting) tracer is injected into the patient. Then the patient is run through a scanner that can detect the emitted positrons along with the position of the emission source in the patient's body. It is typically performed in a scanner that has both CT and PET capabilities. The PET imagery itself is relatively low resolution and does not show anatomy. By combining it with CT, the resulting images can clearly show the emission sources in the spatial context of the anatomy.

The most common tracer is glucose chemically bonded to a radioactive tag. In this way, the PET captures areas of high metabolism. Cancer cells are furiously metabolic, so they are the first to take up the tagged sugar, and they take up more of it. Thus the PET/CT scan of the whole body should show clusters of cancer cells as glowing blobs.

The image to the left (from Wikipedia) is an example. The caption describes it as showing a colorectal cancer that has metastasized to the liver. The blob in the lower abdomen is normal accumulation of the tracer in the bladder, and you can also see normal accumulation in the kidneys. Presumably the colorectal cancer in this patient had been previously removed via surgery as none is visible. You'll also notice at the top of the image that the brain is always highly metabolically active.

My chemist friend John pointed out that PET relies on radioisotopes with pretty short half-lives. You don't want a patient walking around for days or weeks sloughing off radioactive skin flakes or urine. That means that the scanners have to be relatively close to the sources of the isotopes, which originally could only be produced at large linear accelerators. The tech who did my scan said Dana Farber used to get their isotopes from Maryland and batches were flown to Boston daily. If the weather was bad and the tracer didn't arrive, that days scans were cancelled.

An indirect connection of John's apparently got rich by contributing to the invention of devices that could produce the isotopes more easily and locally. Dana Farber's isotopes now come by van from nearby Woburn, MA twice a day.

The tracer is administered by a special machine on wheels. About the size of a portable ultrasound machine. I presume they load it with cartridges of tracer and it shields the techs from the radiation. The tech inserted the IV and flushed it, but then turned on the machine and stood a distance away while I received the tracer. I didn't feel a thing. Then the IV was removed.

I waited 50 minutes for the uptake of the tracer. I suspect the timing is pretty exact: enough time for the cancer cells to take up the labelled sugar but not enough for it to be taken up by most normal cells. Then I walked to the scanner room and laid down on the scanner table.

The CT portion of the scan was performed first and only took a minute or two. Then the PET portion of the scan began. I was moved lengthwise through the scanner with seven or eight different stops, each lasting about 5 minutes. I dozed. The stationary positions are to allow the detectors around the scanner to collect the gamma rays that were radiating from my body. Obviously the tracer is not highly radioactive as that would be damaging to the patient. So the detectors take a while to collect enough radiation to supply a good signal for imaging.

Then it was over.

I mentioned previously that we are leaving this weekend for Something Really Fun before life gets even more abnormal during treatment. In the waiting room, Wonderful Wife and I discussed whether we wanted to know the results of the PET scan before our family trip. We decided we would not ask Doctor Rad. If she had good news she would tell us. If she didn't tell us we could pretend it was because she didn't know yet and enjoy our vacation in ignorance.

Now we had an hour to kill before we had to be at Brigham and Womens Hospital on the next block for the radiation therapy planning CT scan with Doctor Rad. Wonderful Wife had never seen the Harvard Medical School quad, so went there and sat on a bench and talked.

We've been doing a lot of talking lately. Wonderful Wife has that moniker for a reason. She was already exceedingly wonderful even before cancer showed up.

At 2:00 we headed over to Brigham and Womens and found the Radiation Oncology department in the basement. A volunteer was sitting in the hall near the registration desk playing the harp. I guess if the radiation doesn't work there's always heaven to look forward to.

I changed into a robe and went into a treatment prep room and got another IV. The nurse told me she always asks if a patient has other procedures that day because the PET tech could have just left mine in from earlier. Oh well. Fortunately I don't mind needles at all. After a few more minutes of waiting we were taken to the scanner room where we were joined by Doctor Rad and a bunch of other people.

I described IMRT (Intensity Modulated Radiation Therapy) in a previous post. When I receive radiation therapy it will be via a multiple beams that are focused, moved and modulated by computer. But the preparation for the treatment requires that Doctor Rad and a team build a precise map of my head, including the internal structures, so they can sculpt the radiation pattern to hit the cancer but leave as much non-cancer tissue undamaged. This planning session gives them a calibrated scan with which to do that.

Also, since I will have 35 radiation treatments (5 days per week for 7 weeks) they need to make sure that the beams are properly aligned with my head and neck, identically at each treatment. In the past they did that with small tattoos, which they would then align with a laser before each treatment. But now they make a custom plastic mesh mask that will hold my head and shoulders even more precisely. They will bolt me to the table!

The photo shows my mask just after they finished making it and marking it for alignment with the treatment machine. They told me I can have it when treatment is over. We joked that we'll hang it on the wall. Mom, however, tells me I'll hate that mask by the time treatment ends.

After the CT session was over I joined Wonderful Wife in a small private waiting room just off the scanner room. I showed her the mask. Then Doctor Rad joined us.

I had some questions I had written down to ask her. She addressed those quickly.

Then Doctor Rad mentioned that the first look at the PET scan looked good. I told her that I had gotten myself pretty scared that the PET scan would not be clean. She said she would go check, then quickly came back and told me that it was indeed clean. She added that the pathology second read was also complete and my tumor was confirmed as HPV positive.

I burst into tears.

The two things that could indicate a worse prognosis for me were eliminated.

The relief I felt was enormous. I sobbed.

With that news, our diagnosis chapter came to an end, one month to the day from when I first saw Doctor W about a sensation in my throat. It has been one very long month. A slow-motion emotional rollercoaster. Somehow we survived all that uncertainty and fear.

I now officially reside in the diagnostic category with an 80% 5-year survival rate. Even Doctor Rad seemed relieved.

It seems weird to be ecstatic about having a cancer with only a 20% chance of killing me. But I'll take it.

Treatment is scheduled to begin June 19. Sooner if Doctor Rad can arrange it.

Have I mentioned that I feel relieved?

1 comment:

  1. This Picture of the plastic mesh mask brings home to me just how similar Our stories are, I have an almost identical picture on my blog. If you don't mind, I will send you a separate email With a couple of questions for you. (I you DO mind, you can tell me when you reply to my mail ;-)[feeble attempt at humor]

    ReplyDelete