As I mentioned in my last post, I have received the pathology reports from my latest serum and urine electrophoresis and immunofixation tests, as well as my bone marrow biopsy. A major objective of my treatment protocols to date has been to achieve as good a response as possible, so let me review the criteria. I warn you that I'm going to throw a few acronyms at you, so bear with me.
The criteria for achieving Complete Response (CR) consists of all of the following:
- Negative blood serum immunofixation
- Negative 24-hour urine immunofixation
- Less than 5% plasma cells in bone marrow
The use of multiparameter flow cytometry (MFC) on the bone marrow aspirate allows the definition of an immunophenotypic response (IR), which is a much more sensitive indicator of residual MM cells than the blood or urine immunofixation results. IR has recently been accepted as the next level of response beyond sCR. Study results have shown that achieving IR provides substantial benefits for extending Progression Free Survival (PFS) over CR and sCR. The effect on Overall Survival (OS) is not as clear, but there hasn't been enough time yet to get definitive statistics.
Prior to my stem cell transplant, I believe I had achieved a Complete Response (CR). My FLC ratio was 0.89, but there was still 1% plasma in my marrow, which may have been monoclonal and showed the possibility of persistent involvement by the MM. The MFC results from February showed the possibility of minimum residual disease.
Subsequent to my ASCT, the serum electrophoresis and immunofixation results began showing a faint M-Spike, as well as a double IgA and IgG gammopathy. I was quite concerned about this, but Dr. Richardson assured me that this was a transient effect from the transplant and should go away with time. I was pleased to find that my latest serum and urine electrophoresis and immunofixation results showed no M-Spike and no monoclonal gammopathy, so the transient effect has disappeared, as Richardson had forecast. Furthermore, my FLC ratio is still normal at 1.06.
The latest bone marrow biopsy results showed about 2% plasma in the bone marrow. However, the MFC results showed the plasma to be polytypic rather than monoclonal. The conclusion was that features of myeloma were not seen in the analysis! Thus, there does not appear to be any indication of minimum residual disease.
I emailed Dr. Richardson to ask whether these results show that I have achieved sCR, to which he responded that I have. Furthermore, the negative MFC result implies that I may have achieved IR as well! This is really good news. It appears that the stem cell transplant followed by the consolidation therapy has in fact deepened my response.
If it hadn't been for my family crisis this past week, I might have been in a more celebratory mood. While every case is different, I have reason to hope that I may enjoy an extended period of remission from MM before it ultimately progresses. By then, I hope either a cure has been discovered or more effective drugs have been developed to control it. I'm very optimistic, but I keep my fingers crossed.