The independent adverse prognostic significance of 1q21 gain/amplification in newly diagnosed multiple myeloma patients.

Objective: 1q21 gain/amplification (1q21+) is a common abnormal karyotype in multiple myeloma, and its proportion in Chinese patients is much higher. If 1q21+ is included as one of the poor prognostic factors, it will greatly increase the proportion of high-risk patients in newly diagnosed multiple myelome (NDMM) patients. Therefore, the poor prognostic significance of 1q21+ is still controversial. This study mainly analyzed the clinical characteristics, treatment response and prognostic significance of 1q21+ in NDMM patients. Methods: 248 NDMM patients admitted in The First Affiliated Hospital of Soochow University from September 01, 2018 to August 31, 2021 of a VRD registration study, were retrospectively analyzed. 135 cases (54.4%) had 1q21+ by CD38-sorted fluorescence Results: Compared with negative patients, 1q21+ patients were more likely to have anemia, hypoalbuminemia, renal insufficiency, high lactate dehydrogenase and high proportion of R-ISS-III stage. The patients with 1q21+ involving CKS1B detected by Cytoscan had a higher proportion of complex karyotypes and abnormal CNVs, and all at middle-risk or high-risk groups defined by Prognostic Index. Multivariate analysis showed that 1q21+ was an independent adverse prognostic factor (PFS HR=2.358, 95%CI 1.286-4.324, P=0.006; OS HR=2.598, 95%CI 1.050-6.425, P=0.039). 1q21+ subgroup had an inferior outcome (PFS P=0.0133, OS P=0.0293). Furthermore 1q21 amplification had a shorter PFS than 1q21 gain (24 months vs not reached, P=0.0403), but the OS difference was not clinically significant. The proportion of 1q had no effects on prognosis. In addition, 1q21+ in main clone rather than subclone was an adverse factor affecting the prognosis (PFS P=0.0172, OS P=0.1260). Autologous stem cell transplantation can effectively improve the survival of 1q21+ patients (P<0.05). Conclusion: Patients with 1q21+ have clinically significant end-stage organ damage and higher tumor burden, more likely to combine 13q14-, t(4;14), 1p32- and other cytogenetic abnormalities. 1q21+ is an independent high-risk cytogenetic factor for poor prognosis in NDMM patients, of which 4 or more copy numbers and main clone position significantly associated with prognosis results.