A prospective, multicenter, randomized trial comparing pamidronate administration (60–90 mg once a month for 1 year) versus simple observation in 177 patients with asymptomatic myeloma was performed to explore whether the administration of this drug reduces the rate of and/or the time to progression to overt, symptomatic disease. No relevant side effects were recorded in pamidronate-treated patients. With a minimum follow-up of 5 years for live patients, there were 56/89 (62.9%) progressions in the pamidronate-treated group and 55/88 (62.5%) within the controls (p = NS). Median time to progression was 46 and 48 months, respectively (p = NS). Overall survival was also similar between the two groups. Skeletal-related events at the time of progression were observed in 40/55 (72.7%) controls, but only in 22/56 (39.2%) pamidronate-treated patients (p = 0.009). In conclusion, the administration of pamidronate in asymptomatic myeloma, while reducing bone involvement at progression, did not decrease the risk of transformation and the time to progression into overt myeloma.

The best therapeutic approach for primary plasma cell leukemia (PPCL) remains unknown so far. In very limited studies, the poor clinical outcome of this aggressive variant of multiple myeloma seemed to be ameliorated by the use of the proteasome inhibitor bortezomib. Aiming to provide more consolidated data, this multicenter retrospective survey focused on unselected and previously untreated PPCL patients who had received bortezomib as frontline therapy. Twenty-nine patients with PPCL were collected. Bortezomib was given at standard doses and schedules, in various combinations with dexamethasone, thalidomide, doxorubicin, melphalan, prednisone, vincristine, and cyclophosphamide. An overall response rate of 79% was observed, with 38% of at least very good partial remission. Grade 3–4 hematological, neurological, infectious, and renal toxic effects occurred in 20%, 21%, 16%, and 4% of patients, respectively. After a median follow-up of 24 months, 16 patients were alive (55%), 12 of whom were in remission phase and 4 relapsed. The best long-term results were achieved in patients who received stem-cell transplantation after bortezomib induction. Bortezomib, used as initial therapy, is able to increase the percentage and the quality of responses in PPCL patients, producing a significant improvement of survival.