Overall survival patterns in patients with multiple myeloma in the era of novel agents and the role of initial clinical presentation and comorbidities: A population-based study

Introduction Clinical trials have shown improved response rates, progression-free survival and overall survival (OS) in patients with multiple myeloma (MM) when using the novel agents thalidomide, lenalidomide and bortezomib. However, outcome data provided by population-based registries, reflecting real-life, report predominantly improved OS in younger MM patients and only minimal improvement in OS in unselected MM patients older than 65 years. Population-based studies in unselected MM patients in the era of novel agents are relatively limited. Explanations for the marked variation in prognosis across patients may in part be explained by the heterogeneity in the initial clinical presentation, the pre-existing comorbidities, disease biology and response to the therapy. Specific end-organ damage caused by the disease, such as hypercalcemia, renal failure, anemia and bone lesions known as the CRAB symptoms may be associated with worse prognosis in the elderly MM patients. This descriptive prospective population-based cohort study was designed to determine the OS in patients with MM in Friesland, The Netherlands in the era of novel agents, and to analyze the influence of the CRAB symptoms and comorbidities at initial presentation on survival. Methods Since 2005 all patients diagnosed with hematological malignancies in Friesland, a province of the Netherlands, are prospectively registered and followed by their clinicians in a population-based registry, the HemoBase. For this analysis, data on clinical characteristics, comorbidities, treatment and outcome of all patients with newly diagnosed MM in Friesland during the period of January 2005 to January 2013 with a follow-up until January 2014 were retrieved from HemoBase. Supplementary information was obtained from the individual patient hospital records. Both symptomatic and asymptomatic patients were included in the study with subgroup analysis on the symptomatic patients. According to the guidelines from IMWG, each CRAB symptom was divided into two categories (11 mg/dL impaired renal function at initial presentation were significantly correlated with worse median OS.