Role of chromosomal 1p/19q co-deletion on the prognosis of oligodendrogliomas: A systematic review and meta-analysis

• Main Authors: Nan Hu, Rachel Richards, Randy Jensen
• Format: Article
• Language: English
• Published: Elsevier 2016-09-01
• Series: Interdisciplinary Neurosurgery
• Subjects: Oligodendroglioma; Chromosomal 1p/19q co-deletion; Overall survival; Progression free survival; Hazard ratio; Standardized mean difference
• Online Access: http://www.sciencedirect.com/science/article/pii/S2214751916300378

Background: The impact of chromosomal 1p/19q co-deletion on the prognosis of oligodendrogliomas has been measured in many studies previously. However most studies used 1p/19q co-deletion as a covariate to be adjusted for in a multivariable model that aimed to assess treatment effects, thus not directly measuring the effect of the 1p/19q co-deletion on prognosis. We conducted a systematic review and meta-analysis to synthesize the results and provide insight on how 1p/19q co-deletion affects prognoses of WHO grade II/III oligodendrogliomas. Methods: Weighted mean difference (WMD), standardized mean difference (SMD), and hazard ratios (HRs) were used to report pooled effect of 1p/19q co-deletion on prognosis of oligodendrogliomas. The Meta-ANOVA model was used to obtain the pooled HRs. Results: The difference in median overall survival (OS) time is 0.24 (95% CI: 0.15 to 0.33) and the WMD for 5-year OS rate is 6.87% (95% CI: 6.66% to 7.07%), favoring patients with co-deletion. The pooled hazard ratio (HR) for mortality is 0.28 (95% CI: 0.13 to 0.62), favoring 1p/19q co-deletion. For progression free survival (PFS), the SMD of median PFS time is 0.13 (95% CI: 0.04 to 0.21), in favor of 1p/19q co-deletion. When comparing therapies among patients with 1p/19q co-deletion, we found that those receiving radiation therapy (RT) and chemotherapy (CT) had a significantly better prognosis than those who received RT only, with pooled HR of 0.64 (95% CI: 0.51 to 0.80). Conclusions: Our pooled results show that chromosomal 1p/19q co-deletion has a significant protective effect on prognosis of grade II/III oligodendrogliomas.