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The Numbers

Posted by Frederick Wasti
Jan 24 2013

Yesterday we were at Dana-Farber once again, and it was a long day, since I had not only an Alemtuzumab (Campath) injection, but also an Ofatumumab (Arzerra) infusion (following the requisite premedications, of course, including an infusion of Methylprednisolone).

Actually, the day was longer than it really had to be, though, since there seemed to be some confusion as to which day of which Part C cycle in my clinical trial I should have been on as a result of missing one Alemtuzumab injection while I was in Brigham and Women's Hospital with pneumonia. We had previously been told that I would merely continue where I left off (which would have pushed everything in Part C two weeks into the future), but it had been decided very recently (and we were unaware of this until we arrived at D-F yesterday morning) that the one missing Alemtuzumab injection would instead be skipped, and that I would go back to following the original Part C schedule.

The result of the above was that, rather than having the last Alemtuzumab injection in Cycle 2 of Part C, I instead would receive both Ofatumumab and Alemtuzumab, since yesterday then became the first day of Cycle 3. There was extra, wasted time involved while everyone checked with everyone else, and it was all a bit frustrating for Diane and me, since the short day (one injection) had been replaced with a longer day (one injection and one lengthy infusion), and additional time was spent while we waited for everyone to get their proverbial ducks in a row. However, the actual treatments yesterday (once it had been finally decided what they were going to be) did proceed quite routinely, so that was good news anyway.

My blood was tested (of course), and I was pleased with the overall results. So, let's take a look at the latest numbers.

First, here is how my total white cell count has looked throughout the trial, up through yesterday:

Remembering that anything between about 5,000 and 10,000 leukocytes per microliter is pretty normal, it can be seen that I reached the normal range early last summer and have remained there ever since. This is good news by itself, of course, but it only shows the total number of white cells, and not the proportions of each type. So, let's take a look at "the usual suspects", i.e., the lymphocytes and the neutrophils.

Here's the graph that shows how the percentages of lymphocytes and neutrophils have varied during the trial:

It can be seen that the percentage of neutrophils still remains at over 90% of my leukocytes, while lymphocytes are still very, very low. Nonetheless, it can be seen that the very large difference between the two percentages has decreased slightly since Part C (with its less intensive "maintenance" protocol) began in December. I am not too concerned here about the neutrophil percentage - it is the lymphocyte percentage that has attracted my attention, since the lymphocytes (which Parts A and B greatly reduced in number) have started slowly growing back.

Now, I do want to emphasize the good news, though - while there has been an increase in the number of lymphocytes, it is good to have ~some~ lymphocytes, since they are (when they are non-leukemic and function correctly) an important part of a healthy immune system (which is something I certainly do not have right now, as evidenced by my recent pneumonia). I did ask Dr. Fisher what he thought about the increase in lymphocytes, and he first reminded me that I could certainly use a few more lymphocytes, and then he suggested that the new cells (hopefully) might all (or at least mostly) be normal (non-leukemic) lymphocytes. (In a few weeks I will be having another CT scan, to see if my spleen and lymph nodes have remained small or have started filling up with lymphocytes, and a bone marrow biopsy, to get an idea whether lymphocyte production in my marrow seems abnormal or not.)

Anyway, looking at the graph of the absolute number of lymphocytes,...

...it certainly doesn't seem as if the lymphocytes have grown at all in number. However, the exaggerated vertical axis on the graph (because there were ~so~ many lymphocytes in my blood at the start of treatment) helps to hide the fact that they have indeed increased a little bit.

Similarly, looking at the graph of the absolute number of neutrophils,...

...it can be seen that they may have decreased just a bit as of late, but that I still have plenty of them, since the normal range is from 2,000 to 6,400 per microliter.

Finally, there is one additional factor to consider when judging the percentages of neutrophils and lymphocytes: Before the trial started, and for most of Part A, I did have a small but significant number of monocytes (which are supposed to normally make up 5 to 12% of the total white cells). Then, during Part B, the monocytes were decimated. However, During Part C, the monocytes have bounced back. This can be seen in a graph of the percentage of monocytes during the trial,...

...as well as in a graph of the absolute number of monocytes (normally 0.2 to 0.9 in thousands per microliter),...

The obvious drop in monocytes during Part B and their modest recovery in Part C is easily explained: Alemtuzumab attaches itself to any cell with CD-52 molecules on its surface, which eventually results in cell death. In part B, I was given quite a bit of Alemtuzumab (three times a week for five months), in order to attack my leukemic B-lymphocytes, which do have CD-52 antigens on their surface. However, normal B-lymphocytes, as well as T-lymphocytes and monocytes, also have CD-52 on their surface, so they are also killed as "collateral damage". So, in Part C, where I am now given Alemtuzumab much less frequently (once every other week), as compared to Part B, it is gratifying to see the monocytes making a comeback. (<smile>)

And so, the recent increases, both in the absolute number of monocytes and in the percentage of monocytes, also help explain why the percentage of neutrophils seems to have dropped a bit lately (i.e, the drop in the percentage of neutrophils is not just due to the slight drop in the absolute number of neutrophils and to the slight increase in the absolute number of lymphocytes).

So, all in all, and despite some of the frustrations from yesterday's confusion, the bottom line from yesterday's blood tests do show some pretty darn good numbers. (<smile>)

Categories: Leukemia