A survival analysis of surgically treated incidental low-grade glioma patients

Abstract

To evaluate the surgical effect on survival in patients with incidental low-grade glioma (LGG) through comparison between asymptomatic and symptomatic patients. The medical records of surgically treated adult cerebral incidental LGG (iLGG) patients in our department between January 2008 and December 2015 were retrospectively reviewed. The survival of patients was calculated starting from the initial imaging diagnosis. Factors related to progression-free survival (PFS), overall survival (OS) and malignant progression-free survival (MPFS) were statistically analyzed. Seventy-five iLGG patients underwent surgery: 49 in the asymptomatic group, who underwent surgery in the asymptomatic period, and 26 in the symptomatic group, who underwent surgery after the tumor had grown and the patients had developed tumor-related symptoms. Significantly more tumors were initially located adjacent to the functional area in the symptomatic group than in the asymptomatic group (P < 0.05), but there was no significant difference in the total resection rate between the two groups. The incidence of postoperative complications (15.4%) and postoperative epilepsy (23.1%) was higher in the symptomatic group than in the asymptomatic group (4.1% and 10.2%, respectively). Multivariate analysis showed that surgical timing, namely, surgery performed before or after symptom occurrence, had no significant effect on PFS, OS or MPFS, while total resection significantly prolonged PFS, OS and MPFS, and the pathology of oligodendroglioma was positively correlated with PFS and OS (P < 0.05). Surgical timing for iLGGs should facilitate total resection. If total resection can be achieved, even after symptom occurrence, patients can achieve comparable survival benefits to those treated with surgery in the asymptomatic phase.

Systematic review—Time to malignant transformation in low-grade gliomas: Predicting a catastrophic event with clinical, neuroimaging, and molecular markers

“… 47 Similarly, gross total resection (GTR) conferred a positive prognostic effect. 9 , 33 , 34 , 38 , 54 , 57 Furthermore, first line surgical resection compared to surveillance 20 partial resection compared to biopsy 33 , 34 and subtotal resection also compared to biopsy 33 were all found to have a positive prognostic effect. Similarly, a postoperative residual tumour volume of ≤5 ml resulted in delayed MT compared to greater residual volumes.…”

Malignant Progression of Diffuse Low-grade Gliomas: A Systematic Review and Meta-analysis on Incidence and Related Factors

“…Because the molecular subtypes are crucial in the transformation of LGG, we determined the rates in tumors of IDHm with and without Codel. The extracted data from Kaplan-Meier curves from four studies with Htrans 4 , 23 , 26 , 27 ) and four studies with Ctrans 11 , 12 , 14 , 52 ) are presented in Fig. 2A-D .…”

Brain Gliomas and Ollier Disease: Molecular Findings as Predictive Risk Factors?

“…Therefore, once a diagnosis of OD with IDH R132H mutation is made, we consider it be useful to perform close surveillance through brain contrast-enhanced MRI, to detect possible early stage gliomas, when still asymptomatic, of small size, without compromission of the neurological functional areas nor vital neurovascular structures, so to plan the best tailored management. The incidence of postoperative complications and seizures is higher in patients with symptomatic compared to those with incidental low-grade glioma [ 43 ] and the overall survival (OS) of incidental low-grade glioma (LGG) patients treated with surgery is better than that of symptomatic LGG patients [ 39 , 44 ].…”

“…The median silent phase of glioma, defined as the time from the generation of the tumor to the occurrence of tumor-related symptoms, was estimated by Pallud et al to be about 12 years (range 1.6–39.4 years) [ 45 ], and the average growth rate of LGG is 2.7 mm/year (range from 1 to 5 mm) [ 43 ].…”

“…Being the extent of resection the main predictive risk factor of progression free-survival (PFS), overall survival and malignant progression free-survival (MPFS) in glioma patients [ 43 ], the possibility to detect a glioma in early stage, when of a small size, should allow to achieve the maximal safe tumor resection preserving the patient’s quality of life.…”