Rising Incidence of Glioblastoma Multiforme in a Well-Defined Population

Background and Objectives The incidence of glioblastoma multiforme (GBM) ranges from 0.59 to 5 per 100,000 persons, and it is on the rise in many countries. The reason for this rise is multifactorial, and possible contributing factors include an aging population, overdiagnosis, ionizing radiation, air pollution and others. The aim of this study is to conduct an epidemiological study of GBM in a well-defined population over a 10-year period and determine its significance, while comparing results with international standards. Materials and Methods All histological diagnoses of GBM in Malta from 2008 to 2017 were identified. Poisson regression was used to determine significance in incidence variation. Log-rank tests were used to compare the survival distributions of each variable. Cox regression for survival analysis with the Breslow method for ties was then performed to consider the overall model. Results A total of 100 patients (61 males; mean age 60.29±10.09 years) were diagnosed with GBM over the period 2008 to 2017. There was a significant increase in incidence from 0.73 to 4.49 per 100,000 over the 10-year period (p≤0.001). The most common presenting complaint was limb paresis (29%). Approximately 65% of patients were treated with maximum safe resection (MSR). Using Cox regression analysis, younger age at presentation and treatment with MSR significantly improved survival (p=0.026 and p≤0.001, respectively). The median survival was 10 months. Conclusions An increasing incidence of GBM is becoming evident, while the median survival remains low. This troubling trend emphasizes the importance of further research into GBM etiology and treatment.