Management of Diffuse Low-Grade Glioma (DLGG) relies extensively on tumor volume estimation from MRI datasets. Two methods are currently clinically used to define this volume: the commonly used three-diameters solution and the more rarely used software-based volume reconstruction from the manual segmentations approach. We conducted an initial study of inter-practitioners' variability of software-based manual segmentations on DLGGs MRI datasets. A panel of 13 experts from various specialties and years of experience delineated 12 DLGGs' MRI scans. A statistical analysis on the segmented tumor volumes and pixels indicated that the individual practitioner, the years of experience and the specialty seem to have no significant impact on the segmentation of DLGGs. This is an interesting result as it had not yet been demonstrated and as it encourages cross-disciplinary collaboration. Our second study was with the three-diameters method, investigating its impact and that of the software-based volume reconstruction from manual segmentations method on tumor volume. We relied on the same dataset and on a participant from the first study. We compared the average of tumor volumes acquired by software reconstruction from manual segmentations method with tumor volumes obtained with the three-diameters method. We found that there is no statistically significant difference between the volumes estimated with the two approaches. These results correspond to non-operated and easily delineable DLGGs and are particularly interesting for time-consuming CUBE MRIs. Nonetheless, the three-diameters method has limitations in estimating tumor volumes for resected DLGGs, for which case the software-based manual segmentation method becomes more appropriate.