The Zytiga does not appear to be working very effectively. My PSA has continued to rise in spite of the new treatment:
2014-03-18 7.8 2014-04-14 9.4 2014-05-12 10.6 2014-06-01 begin Zytiga 2014-06-23 21.5
If you plot those on a graph, it looks a lot like an exponential growth curve. I can just imagine somebody in a bad SF movie saying “IT’S GROWING EXPONENTIALLY!!!”
Of course, all biological systems grow exponentially (subject to environmental limits), but we’re hoping the treatment either inhibits the growth (possibly even killing it off and making an exponential decay instead of exponential growth) or at least slows the growth, leading to a large time constant.
Unfortunately, doubling in that short a period is not a large time constant. It is growing fast.
The oncologist said he observed that sometimes people have a brief increase in PSA when they start Zytiga, but he’s never seen one this severe. He also says that patients respond more poorly to Xtandi after they’ve had Zytiga. So he recommended chemotherapy.
I’m not convinced by his argument. When the cancer cells become resistant to a treatment, it is because I have evolved resistance to the treatment. I killed everything that treatment could kill, so whatever is left has developed some resistance. But if the Zytiga never worked in the first place, I have not been putting evolutionary pressures on the cancer cells; maybe they have not needed to make adaptations to the Zytiga, and therefore those adaptations will not help them resist Xtandi.
I want more data before choosing the next treatment. So, I’m going to have another bone scan, a CT scan of the thorax, and another blood test. If the PSA has gone down, it might be that I have had a remarkably large PSA jump from starting the Zytiga. I don’t think that is it, though: when the oncologist prescribed it, he said that Zytiga doesn’t work at all for about 1/3 of patients.
The radiological tests are meant to try to find out what the tumor progression looks like. That is, are the tumors bigger or are there more of them? If I have mild tumor progression, that might indicate Xtandi is a reasonable treatment. If I have severe tumor progression, that indicates that chemotherapy should come next. In either case, we also have a new baseline for recognizing further progression.
But since I’m still in the middle of collecting data, I don’t know what the real condition of the cancer is, and I don’t know what I will be doing next. Therefore, I’m calling this a non-update.
None of this looks good, though. The median survival from beginning chemotherapy is about 18 months, but I have not reached
any median duration in any stage of this disease. I’ve known since the diagnosis of the metastasis that this disease is going to kill me, but there was some probability that it might take more time to do it.
Now, it doesn’t look like it. Rather, it looks like I’m going to be one of those people who brings down the average and the median. I don’t like it, because it means I need to get ready to die, maybe in the next year.
Shit de Fuck de Shit de Merde de Tabarnac!