Some recent posts have talked about the possibility of seeing a "bounce" effect, of rising PSA or ALP, as a by-product of treatments such as radiation, BAT, Pluvicto, etc. Rather than indicating disease progression and ineffectiveness of treatment, such upward jumps in the numbers may indicate the death of cancer cells. Counter-intuitively, the bump up may be a sign of EFFECTIVE treatments. (I got such a bump in my ALP when I first began Zytiga: a sharp rise in ALP, to around 1000, a month after beginning Zytiga, was followed by sustained drops that leveled off in the 200s.)
I recently quoted Sam Denmeade saying of BAT that "when prostate cancer cells are exposed to T they are stimulated to make PSA, even if their growth is blocked by T. Thus, we cannot rely on PSA response alone to assess the effectiveness... BAT can [also] induce an initial flare response on the bone scan, as do many other effective prostate cancer therapies. Spots on the bone scan can appear darker, and sometimes new spots that weren't seen before can appear. Patients who appear to be benefiting [can] show an initial worse bone scan..."
So initial signals of progression, both biochemical and radiographic, may be deceiving. But is there anyway of knowing this until future scans, months down the road, actually confirm that progression is not occurring? My worry is, it seems like there is often going to be quite a lag time between the messages one gets (and tries to interpret) from blood work and the messages one later gets from scans, especially if the scans being used are not the most refined in picking up new mets (bone scan, CT).
To put this in the context of my own case, the series of CT and bone scans I have had over recent months reveal my disease to be "stable." Under the protocols being used to define "progression" within the Lu-177 arm of the Pluvicto trial I am in, my disease is not progressing. The lumbar CT I just had on Friday, due to some lower back pain, for example, said this: "Alignment is normal. Vertebral bodies and posterior elements are intact. Normal disc heights and endplates. No prevertebral soft tissue thickening. No significant change in multifocal predominantly sclerotic osseous metastases."
That last line seems to be the story of my treatment. But here is how the PSA and ALP numbers have progressed on Pluvicto (which I began on 4/5, and had a fifth infusion of on 10/21):
4/5, PSA 21
5/11, PSA 2.5 (Nice!)
6/2, PSA 14
7/29, PSA 33
9/6, PSA 40
10/21, PSA 50
ALP
4/5, ALP 355
6/2, ALP 243
7/29, ALP 335
9/6, ALP 298
10/21, ALP 644
I wasn't overly concerned about the rising PSA, because my stable (and even dropping!) ALP numbers seemed to confirm my disease maybe still could be relatively stable. I have yet to experience any significant bone pain that can be directly attributed to mets. But this last ALP number, from Friday, is truly alarming. Yet the PA I met with on Friday did not seem overly concerned by it, and implied that my MO would not be, either. (I have yet to speak with him but will obviously be addressing my worries.)
How would I not suppose this doubling of ALP might represent progression of bone mets that aren't yet being picked up on bone or CT scans? It seems almost impossible that this ALP number could reflect the "good news" that my Pluvicto treatments are a success. Yet by the trial definition of radiographically-determined progression, I am NOT progressing on Pluvicto!
Definition of Biochemical Failure
Final Pluvicto shot and things OK
SABR to oligometastases slows progression via immune response
