Thanks for mentioning oligosecretory myeloma. I thought about adding it into the mix, but I held back, mainly because I didn't want to overcomplicate things.
Also, I have the impression that, as the free light chain assay is used more and more to monitor multiple myeloma patients, fewer myeloma specialists are using the "oligosecretory" classification. Instead, patients are mainly being classified into the three broad categories I described earlier in this thread -- "regular" (both an M-spike and elevated free light chains present), "light chain only", and "nonsecretory".
I agree, though, that some (many?) of the patients who are being told that they are nonsecretory are probably oligosecretory instead.
The Beacon article you mentioned about oligosecretory disease has an interesting discussion that reflects some of what I wrote earlier in the thread about how multiple myeloma has a tendency to become more nonsecretory as it progresses:
Dr. Rajkumar believes that “as the disease progresses, the myeloma cells become more genetically abnormal and lose the ability to synthesize and/or secrete monoclonal proteins,” causing oligosecretory disease.
However, Dr. Rachid Baz from the Moffitt Cancer Center, who was not involved with the study, is not completely convinced that oligosecretory disease becomes more prevalent in advanced stages of myeloma.
He explained that spikes in M-protein levels are high in newly diagnosed patients, but low after treatment, and that retreatment often begins before M-protein levels are measurable again.
“In this situation, the patient would be labeled as having oligosecretory disease while, in fact, if that patient had waited longer to start therapy, his/her M-spike may have reached measurable levels,” he said.
