Newly Diagnosed Multiple Myeloma Patients with 1q21 Amplification Treated by Autologous Stem Cell Transplantation Have Shorter Progression-Free Survival Interval.

Amplification of chromosome band 1q21 as well as increased expression of CKS1B gene in this area is a frequently mentioned prognostic factor for patients with multiple myeloma (MM). Total 39 newly diagnosed multiple myeloma patients (median age: 56 years) enrolled in Faculty Hospital Brno, Brno, Czech Republic, were examined for 1q21 amplification status. All patients received 4 cycles of vincristine, adriamycin and dexamethasone (VAD) as induction and one course melphalan 200mg/m² followed by autologous stem cell transplantation (ASCT). The median follow-up from treatment start was 16.1 (range: 2.2–44.0) months. All the “end-point” intervals and treatment responses were assigned by IMWG criteria. Plasma cells were identified by cytoplasmic light-chain immunofluorescence followed by fluorescence in situ hybridisation (cIg-FISH). Amplification of 1q21 (Amp(1q21)) was assigned utilizing labelled BAC clone (RP11-205M9) DNA probe. Cut-off level for Amp(1q21) was established to 10% of total amount of cells with additional signals detected. Amp(1q21) was found in 41% (16/39) patients. Clinical parameters valid for patients with Amp(1q21) versus patients lacking Amp(1q21) were as follows: overall response rate (ORR) achieved 87.5% (14/16) vs. 91.3% (21/23) patients (p=0.404); overall survival (OS) median was 22.4 months vs. not yet reached (p=0.022); time to progression (TTP) median was 16.1 months vs. not yet reached (p=0.010); progression-free survival (PFS) median was 15.6 months vs. 25.2 months (p=0.023) and duration of response (DOR) median was 15.9 months vs. not yet reached (p=0.048). There were found statistical significant difference in all named “end-point” intervals (OS, TTP, PFS and DOR) between patients with/without Amp(1q21) but not in ORR. In conclusion, patients with Amp(1q21) treated by ASCT have significant shorter PFS median (15.6 months) when compared with patients lacking Amp(1q21) with PFS median 25.2 months (p=0.023). This findings is in accordance with previously published work (Chang et al., 2006).