Purpose: A meta-analysis was performed to compare survival after treatment with melphalan and prednisolone (M + P) with that after combination chemotherapy (CCT) in patients with multiple myeloma.
Methods: Meta-analysis was performed on 18 published trials comprising 3,814 patients comparing M + P with CCT. Two-year survival percentages with observed and expected deaths at 2 years were calculated for each trial, and the overview methodology was applied to these figures.
Results: Overall results from the 18 trials suggest that there is no difference in efficacy between the two treatments. This finding, however, masks a highly significant correlation between 2-year survival rates for M + P-treated patients in individual studies and the difference between the M + P and CCT 2-year survival rates for that study (r = .69; P = .0008). In separate overviews, those studies with a high M + P 2-year survival rate showed a survival difference in favor of M + P (P = .02), whereas those with a low rate suggested a difference in favor of CCT (P V .07). Comparison of the 2-year survival rates in the M + P treatment arms of each of the studies with available data showed an inverse correlation between survival and the proportion of patients with either poor performance status (P less than .001) or immunoglobulin A (IgA) M band (P = .02).
Conclusions: These results imply that M + P is superior for patients with an intrinsically good prognosis and inferior for those patients with a poor prognosis. If reliable prognostic factors can be established for this disease, they could be used to select therapy for individual patients.