Treatment attrition and outcomes of myeloma patients in Finland: a real-world study.

background and purposeRelapses, need for further treatment lines and significant treatment attrition are typical for multiple myeloma (MM). This retrospective study investigates attrition and outcomes among MM patients in Finland. Patient, material and methods: Study included all adult MM patients (n = 1733) diagnosed and treated in four hospital districts in Finland in 2013-2022. Data were collected from hospital data lakes, Statistics Finland and Social Insurance Institution. Treatment attrition was defined as death before next treatment line.

resultsBy the end of follow-up 31% of patients without stem cell transplantation (non-SCT) had died before initiation of second line treatment (2L), compared with 5% of stem-cell transplant (SCT) patients. The factors associating with this early attrition in the non-SCT cohort were older age (over 75 years), higher comorbidity burden, International Staging System (ISS), and (R)-ISS scores (p < 0.001). Furthermore, non-SCT patients were more likely administered less intensive therapy during 1L (p < 0.001). During the first 6 months post diagnosis in the non-SCT cohort, the most common immediate cause of death was MM. Also, during later stages MM was responsible for 54% of deaths in the non-SCT and 68% in the SCT cohorts whereas infections were linked principally with early deaths before 2L treatment.

interpretationThis study highlights significant treatment attrition across disease course and also early mortality especially in the non-SCT cohort resulting primarily from progressive MM or infections. The findings underscore the need for more tolerable and effective anti-myeloma treatments in earlier course of the disease to enhance patient survival.