Six Years of Experience and Outcome with Maintenance Therapy with Very Low Dose Thalidomide after Auto-SCT in Multiple Myeloma

New drugs and high dose therapy with auto-transplantation (auto-SCT) has improved prognosis of multiple myeloma (MM). New drugs are promising in upfront therapy while the role of maintenance is still debated. Thalidomide (thal) is an active drug in the treatment of myeloma, and is been investigated as first line therapy, the limit of this drug is the toxicity dependent dose and this determines a poor compliance. It could be useful in the control of minimal residual disease. We used low dose of thal as maintenance after autologous transplantation in patient with MM from January 2002 and here we bring our experience after six years of observation. From January 2002 to August 2008 17 patients (8 males and 9 females) with MM have been treated in our institution. Median age was 59,5 years (range 48–72). 10 were IgG, 3 IgA, 3 light chains and 1 plasma-cell leukaemia. Treatment was 4 cycles of VAD regimen followed by auto-SCT. 4/17 performed double auto-SCT. Three months after SCT these patients has begun the maintenance with thal 50 mg/die, to start thal maintenance 9 patients were in CR, 5 in PR and 3 in resistant disease and the median somministration of thal has been of 12 months (range 3–24 months). Median follow up from the beginning of maintenance therapy was 40 months (range 4–76) with 11/17 (64%) patients in CR or stable disease, with progression free survival (PFS) and overall survival (OS) projected at 75 months respectively of 53% and 51% from to start thal. In our experience we have observed a neurological toxicity (grade I–III) in the 65% of the patients but only 4 have had to suspend the treatment; a haematological toxicity of grade I in the 55% of the patients that have not behaved interruption of the treatment and finally in any case we have documented thrombotic episodes. Finally we have compared this group of patients with another group (18 patients) with the same clinical characteristics that we have observed in the same period but that have not effected maintenance with thal. In this last group 13/18 patients (72%) relapsed with median follow-up of 36 months (range 14–75) and median PFS and OS of 16 and 30 months respectively. The difference between the 2 groups is statistically significant for PFS (p: 0.003) and OS (p: 0.04). The median overall survival observed after progression, in the two groups, has been of 13 months in thal group and 17 months in the group of patients that have not effected the maintenance, this difference is not statistically different (p:0.06). In conclusion in 6 years of observation our experience has shown, even if the number of the patients is small, that maintenance with low doses of thal, after auto-transplantation, it not only has a good compliance but it improves the PFS and OS in this cohort and it doesn’t worsen the OS from the relapse.