Thanks! That was exactly what I needed. I found a paper from 2014 that cites the paper you linked and corroborates the existence of a radiographically-detectable “flare response” that bone metastases may exhibit in response to successful chemo treatment.
Bone health in cancer patients: ESMO Clinical Practice Guidelines by R. Coleman published in 2014
“The use of bone scanning for assessment of response to therapy has always been contentious, and is certainly unreliable when lytic metastases predominate. After successful therapy for metastatic disease, the healing processes of new bone formation cause an initial increase in tracer uptake (akin to callus formation), and scans carried out during this phase are likely to show increased intensity and number of hot spots. After treatment for 6 months, the bone scan appearances might improve, as the increased production of immature new bone ceases and isotope uptake gradually falls. This ‘deterioration’ followed by subsequent ‘improvement’ in the bone scan appearances after successful therapy has been termed flare response.”
It is positive to hear that your mother-in-law’s scan showed response to treatment.
I have seen some references to the phenomenon you describe. I believe it is called “flare” or “flare response.” In other words, the first step in a positive response looks like a worsening. If you google that term you may find more information.
Here is one article. If not directly helpful, maybe it will suggest routes to look for further materials. (Being a patient and not a medical expert, I cannot comment on how recognized this article is.)
My mother-in-law had her first CT after her initial chemo cycle and the results were mixed. The primary tumor and neighboring metastases seem to be responding to the chemo, but the metastases in her spine and pelvis appear to be growing.
The doctor reading her CT suggested that bone metastases can appear to grow when they are actually responding to the chemo because of the bone’s wound healing process.
Has anyone heard of this? If anyone has papers or posts to share, please send them along! I want to get a better understanding of what the results of the CT scan mean.