Patterns of outcome in patients with essential monoclonal gammopathy:
— Twenty-five percent of patients progress to develop myeloma, amyloidosis, macroglobulinemia, lymphoma, chronic lymphocytic leukemia over a 25-year period of observation. (Approximately 1% per year progress to some form of B-cell malignancy.)
— Twenty-five percent of patients have a modest increase in Ig protein levels over time but do not progress to a B-cell malignancy.
— Fifty percent of patients do not have progression (clonal evolution) during their lifetime.
— Although studies have shown some variables at diagnosis that may predict for earlier progression in groups of patients (eg, higher marrow plasma cell concentrations, higher monoclonal Ig levels, lower levels of polyclonal Ig, abnormal serum light chain ratio), they are not sufficiently predictive in a single patient. In addition, there is no evidence, as yet, that early treatment for an incipient B lymphocyte neoplasm is worthwhile.
— Currently, neither gene expression analysis nor cytogenetic findings are sufficient to predict time of progression.
— Rarely, the monoclonal protein disappears spontaneously.
— Periodic reevaluation is required to determine the stability of the clinical course after diagnosis and to identify evidence of progression during long periods of observation.
— Therapy is generally not required for essential monoclonal gammopathy unless the monoclonal protein impairs the function of a normal plasma (eg, acquired antithrombin) or tissue constituent (eg, neuropathy) (see Table 67–2).