Clinicopathological characteristics of extremely young Korean multiple myeloma patients: Therapeutic implications

Background/Aims: Although multiple myeloma (MM) is typically a disease of the elderly, a certain subset of extremely young patients exists. It is necessary to establish clinicopathological characteristics for this population. Methods: We reviewed the medical records of MM patients whose age was 40 years or younger at diagnosis. Results: A total of 32 patients were analyzed (male to female ratio 19:13, median age 37 years). According to International Staging System, 29%, 48%, and 16% were in stage I, II, and III, respectively. Light chain myeloma accounted for 30%. Clinically significant anemia, hypercalcemia, azotemia, and hypoalbuminemia were present in 29%, 28%, 13%, and 28%, respectively. Three or more lytic bone lesions were detected in 45% of the patients, whereas 13% had no lytic bone lesions. Regarding treatment, 79% of patients received autologous hematopoietic stem cell transplantation. After a median follow-up duration of 64 months, the 1-, 3-, and 5-year overall survival (OS) rates were 84%, 62%, and 54%, respectively. The median OS was 61 months for the entire cohort. Conclusions: In our study, MM patients aged 40 years or younger at diagnosis showed no superior survival compared to those of the moderately elderly patients based on historical data.