gms | German Medical Science

Objective: The effectiveness of surgical treatment of supratentorial low-grade gliomas (LGGs) continues to be debated. For the present paper we have analyzed the influence of the degree of resection (DOR) on malignant progression and patient survival in a series of 126 adult patients treated at our institution.

Methods: We evaluated all patients with infiltrative supratentorial LGGs WHO grade II operated in our institution from 1996–2007 who did not undergo radiation or chemotherapy prior to surgery. Pertinent clinical data were obtained from the patients’ charts and through telephone interviews.

Results: The mean age at diagnosis was 37 years. Mean follow-up was 70.9 months. There were 73 (58.0%) astrocytomas, 38 (30.1%) oligoastrocytomas and 15 (11.9%) oligodendrogliomas. 41 (32.5%) patients underwent a gross-total resection, 68 (54.7%) an incomplete resection, and 17 (13.5%) a biopsy only. The 5-year OS (overall survival) and PFS (progression free survival) rates were 50.0 % and 34.1 %, respectively. Tumor recurrence during follow-up occurred in 88 patients (69.8%). 84 patients had surgical treatment. 60 patients (71.4%) were found to harbor a malignant glioma including 18 (21.4%) glioblastomas. In the multivariate analysis, a greater DOR correlated with longer OS (p=0.031) and PFS (p<0.001). Further independent predictors of survival were KPS≥90 (OS, p=0.036), duration of symptoms >6 months prior to surgery (PFS, p=0.027) and smaller preoperative tumor volume (<25 vs. 25–100 vs. >100 cm³, PFS, p=0.001). Predictors of malignant progression included a lesser DOR (p<0.001) and larger tumor volumes (p=0.011). Age and histology did not correlate significantly with PFS, OS or malignant progression in the multivariate analysis.

Conclusions: A greater degree of resection (DOR) correlates significantly with the patients’ prognosis. These data favor cytoreductive surgery as the therapy of choice for LGG.