Date Published: January 30, 2019
Publisher: Public Library of Science
Author(s): Shuo Liu, Xiaoqiang Liu, Yingxiu Xiao, Shuying Chen, Weiduan Zhuang, Ali Osmay Gure.
Anaplastic oligodendroglioma is a rare disease with an inadequately understood prognosis. The aim of this study was to investigate factors associated with survival outcome in anaplastic oligodendroglioma patients. A population-based cohort study was conducted based on the Surveillance, Epidemiology, and End Results program. In total, 1899 patients with a histological diagnosis of anaplastic oligodendroglioma from 1973 to 2015 were included. Mean age at diagnosis was 49.2 years, and 56.19% were male. In our study, 62.40% of patients were married, and 87.05% were white. Most patients (90.42%) were diagnosed with anaplastic oligodendroglioma as their first malignant primary tumor, but 9.58% had a diagnosis of at least one other primary malignancy; 87.89% of patients had received cancer-directed surgery. Patients receiving surgery had a better prognosis for overall survival compared to those not receiving surgery after propensity score matching analysis (p<0.05). The overall 1-, 3-, 5-, and 10-year survival of anaplastic oligodendroglioma was 78.7%, 60%, 50.2%, and 36.2%, respectively. Kaplan-Meier analysis indicated that age, marital status, presence of multiple primary malignancies, and surgical treatment were associated with overall survival, whereas sex and race were not. Moreover, age at diagnosis of 52 years was calculated as an optimal cutoff value to distinguish better and worse overall survival. Multivariate Cox proportional hazard analysis indicated that older age (OR 1.040, 95%CI1.035–1.045), single patients (OR 1.293, 95%CI 1.103–1.515), and presence of multiple primary malignancies (OR 1.501, 95%CI 1.238–1.820) were significantly associated with worse overall survival, whereas surgery (OR 0.584, 95%CI 0.494–0.689) was associated with better overall survival. A nomogram predicting 5-, and 10-year survival probability for anaplastic oligodendroglioma was constructed based on these variables. In conclusion, age, marital status, presence of multiple primary malignancies, and surgical treatment were associated with survival of anaplastic oligodendroglioma.
Primary central nervous system (CNS) tumors are a diverse group of neoplasms arising from a wide range of CNS cells. They predominantly comprise gliomas. As a group, oligodendrogliomas comprise the third most common type of primary glioma, accounting for 2% to 5% of all primary CNS tumors and 4% to 15% of gliomas. Oligodendrogliomas are tumors of oligodendrocytes and often occur in patients aged 40 to 60 years, with an average age at diagnosis of approximately 45 years.[3,4] The World Health Organization (WHO) has divided oligodendroglioma into low-grade well-differentiated oligodendroglioma (WHO grade II) and anaplastic astrocytoma (AO) (WHO grade III).
In the current literature, most studies investigating the detailed clinicopathological features of AO are small case series due to its low incidence and prevalence. The research evaluating prognostic factors influencing the OS of OA is lacking. Our series of 1899 AO patients is the largest study to date. According to previous studies, oligodendroglioma is frequently encountered at age 40 to 60 years, with an average age at diagnosis of approximately 45 years. In our study, the mean age at diagnosis was 49.2 years, slightly older. AO occurs in both men and women, but is slightly more common in men, with the men to women ratio ranging from 1.1 to 2.0. Concordant with the literature, we observed a higher prevalence in male patients with a men to women ratio of 1.3. We also found that the majority of patients were white and married. The overall mean survival time of AO was 56.0 months in this study, with 1-, 3-, 5- and 10-year survival rates of 78.7%, 60%, 50.2%, and 36.2%, respectively. Two previous studies have reported 5-year survival rates of 49.38% and 53.8% [10,11], similar to ours.
In this study, we analyzed a population-based dataset to investigate the demographic characteristics and prognostic factors of a rare disease. We demonstrated that older age, single marital status, and presence of multiple primary malignancies were independently associated with worse survival outcome, whereas surgery was associated with prolonged survival of patients with AO.