Impact of 1p/19q Codeletion Status in The Outcome of Patients Affected By Oligodendroglioma and Diffuse Astrocytoma: A Retrospective Single Surgeon Series With 1.5 Io-MRI Guided Surgery

Abstract

Purpose: The real impact of the Extent of Resection in respect to the 1p/19q codeletion status in determining the outcomes of Low Grade Glioma (LGG) patients is extensively debated. The aim of this paper is to retrospectively analyze the oncologic outcomes of a homogeneous cohort of LGG patients who underwent surgery by a single operator, first author of the present paper (GDA).Methods: A total of 66 patients suffering LGG who underwent craniotomy for tumor resection were operated on and retrospectively evaluated between 2008 and 2016 in a single center in which the operative theater was equipped with an Io-MRI system. We compared a subgroup of 37 patients suffering from Diffuse Astrocytoma to a second subgroup of 29 patients affected by Oligodendroglioma. Volumetric analyses of the Extent of Resection (EOR) were performed, PFS and OS were accurately recorded and used as endpoint variable, as well as the 1p/19q codeletion status of every patient included in the final cohort.Results: GTR produced a statistically significant survival advantage in respect to those associated with STR. This finding is confirmed even in patients suffering from Oligodendrogliomas (in the 1p/19q codeletion group 73.27 versus 101.73 months p=.0001). Similar findings were confimed for patients affected by Diffuse Astrocytomas(81.63 versus 60.44 months p < 0.012), despite the globally shorter survival.Conclusions: We can affirm that the EOR is an independent predictor of survival advantage. The 1p/19q codeletion is an independent prognostic factor significantly associated to a globally longer survival and a longer time to malignant transformation.