PURPOSE: To evaluate the clinical aspects, diagnoses, prognostic factors, and percent progression of plasmacytoma to multiple myeloma. MATERIALS AND METHODS: 103 medical records of patients suspected of plasmacytoma were surveyed covering the period between 1950 and 1998, and 30 were selected for analysis. Patients were classified into 2 groups: patients who did (n = 17) and did not (n = 13) progress to multiple myeloma. Comparative statistics regarding a variety of clincial aspects were developed. RESULTS: Patients who progressed to multiple myeloma were younger than those who did not (52.3 ± 2.6 vs 62.6 ± 3.4 years; mean ± SEM; P = 0.02). There were no significant differences in gender between groups. A higher incidence of multiple recurrence was observed in patients who progressed to multiple myeloma (75%, P = 0.049). Both groups showed a prevalence of vertebral column injuries. No significant differences were found between groups regarding the disease period (from the onset of symptoms until diagnosis) (P = 0.20) and survival (P = 0.34). The average time to progression from plasmacytoma to myeloma was 41 ± 39 months (mean ± SD), and the progression rate was 57%. CONCLUSION: Patients who progressed to multiple myeloma were younger than those who did not. No significant differences were found between groups regarding sex, time from symptom onset to diagnosis, and survival time. In both groups, the most affected anatomic location was the vertebral column, and most affected sex was male. The average time to progression to multiple myeloma was 41 months. It was not possible to determine the factors that influenced the survival of patients with plasmacytoma or for those who progressed to multiple myeloma.
Plasmacytoma; Multiple myeloma; Clinical progression; Prognosis; Plasma cells
