Cytogenetic Features and Clinical Outcomes of Patients With Non-secretory Multiple Myeloma in the Era of Novel Agent Induction Therapy

Background: Non-secretory multiple myeloma (NSMM) is a rare subtype of multiple myeloma (MM) characterized by the absence of monoclonal protein in the serum and/or urine. We look at the clinical and cytogenetic features of NSMM in this study. Patients and Methods: This study evaluates a cohort of 30 patients with newly diagnosed NSMM seen at the Mayo Clinic, Rochester, MN, between 2008 and 2018 and treated with novel agent induction therapies. Survival outcomes were estimated using the Kaplan-Meier method and compared using the log-rank test. Results: These patients with NSMM appear to have a large disease burden at diagnosis with a median bone marrow plasma cell percentage of 70% and more than one-half of all patients having Multiple Myeloma International Staging System Stage III disease. There was a higher preponderance for t(11;14) primary cytogenetic abnormality in this NSMM cohort, accounting for more than 50% of the cohort. Finally, the overall survival of this cohort appears to be slightly worse than a matched-control group of newly diagnosed patients with MM with secretory disease. Conclusions: Future multi-institution studies confirming these above findings on this rare entity are warranted. Non-secretory multiple myeloma is a rare form of multiple myeloma characterized by the absence of a monoclonal protein in serum and urine. This study looks into the clinical and cytogenetic features of this disease. The study cohort consisted of 30 patients diagnosed between January 1, 2008 and December 31, 2018. The study revealed that there was a preponderance of the t (11;14) cytogenetic abnormality in this group of patients. Compared with a control group of patients with secretory multiple myeloma, matched for age and year of diagnosis, the patients with non-secretory multiple myeloma had worse survival outcomes, but this was statistically insignificant.