Oligodendrogliomas that enhance on MR images are associated with poor prognosis. However, the importance of the volume of enhancing tumor tissue, and the extent of its resection, is uncertain. The authors examined the prognostic significance of preoperative and residual postoperative enhancing tissue volumes in a large single-center series of patients with oligodendroglioma. They also examined the relationship between enhancement and characteristic genetic signatures in oligodendroglial tumors, specifically deletion of 1p and 19q (del 1p/19q).
The authors retrospectively analyzed 100 consecutive cases of oligodendroglioma involving patients who had undergone T1-weighted gadolinium-enhanced MRI at diagnosis and immediately after initial surgical intervention. The presence of preoperative enhancement was determined by consensus. Preoperative and residual postoperative volumes were measured using a quantitative, semiautomated method by a single blinded observer. Intrarater reliability for preoperative volumes was confirmed by remeasurement in a subset of patients 3 months later. Intrarater and interrater reliability for residual postoperative volumes was confirmed by remeasurement of these volumes by both the original and a second blinded observer. Multivariate analysis was used to assess the influence of contrast enhancement at diagnosis and the volume of pre- and postoperative contrast-enhancing tumor tissue on time to relapse (TTR) and overall survival (OS), while controlling for confounding clinical, pathological, and genetic factors.
Sixty-three of 100 patients had enhancing tumors at initial presentation. Presence of contrast enhancement at diagnosis was related to reduced TTR and OS on univariate analysis but was not significantly related on multivariate analysis. In enhancing tumors, however, greater initial volume of enhancing tissue correlated with shortened TTR (p = 0.00070). Reduced postoperative residual enhancing volume and a relatively greater resection of enhancing tissue correlated with longer OS (p = 0.0012 and 0.0041, respectively). Interestingly, patients in whom 100% of enhancing tumor was resected had significantly longer TTR (174 vs 64 weeks) and OS (392 vs 135 weeks) than those with any residual enhancing tumor postoperatively. This prognostic benefit was not consistently maintained with greater than 90% or even greater than 95% resection of enhancing tissue. There was no relationship between presence or volume of enhancement and del 1p/19q.
In enhancing oligodendrogliomas, completely resecting enhancing tissue independently improves outcome, irrespective of histological grade or genetic status. This finding supports aggressive resection and may impact treatment planning for patients with these tumors.
Abbreviations used in this paper:DICOM = Digital Imaging and Communications in Medicine; ICC = intraclass correlation; MIPAV = Medical Image Processing and Visualization; OS = overall survival; TTR = time to relapse; VOI = volume of interest.
Address correspondence to: Mark C. Preul, M.D., c/o Neuroscience Publications, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, 350 West Thomas Road, Phoenix, Arizona 85013. email: firstname.lastname@example.org.
Please include this information when citing this paper: published online March 16, 2012; DOI: 10.3171/2012.2.JNS102032.
AssefaDKellerHMénardCLaperriereNFerrariRJYeungI: Robust texture features for response monitoring of glioblastoma multiforme on T1-weighted and T2-FLAIR MR images: a preliminary investigation in terms of identification and segmentation. Med Phys37:1722–17362010
CairncrossGBerkeyBShawEJenkinsRScheithauerBBrachmanD: Phase III trial of chemotherapy plus radiotherapy compared with radiotherapy alone for pure and mixed anaplastic oligodendroglioma: Intergroup Radiation Therapy Oncology Group Trial 9402. J Clin Oncol24:2707–27142006
CairncrossJGUekiKZlatescuMCLisleDKFinkelsteinDMHammondRR: Specific genetic predictors of chemotherapeutic response and survival in patients with anaplastic oligodendrogliomas. J Natl Cancer Inst90:1473–14791998
GinsbergLEFullerGNHashmiMLeedsNESchomerDF: The significance of lack of MR contrast enhancement of supratentorial brain tumors in adults: histopathological evaluation of a series. Surg Neurol49:436–4401998
JenkinsRBBlairHBallmanKVGianniniCArusellRMLawM: A t(1;19)(q10;p10) mediates the combined deletions of 1p and 19q and predicts a better prognosis of patients with oligodendroglioma. Cancer Res66:9852–98612006
SmithJSPerryABorellTJLeeHKO'FallonJHosekSM: Alterations of chromosome arms 1p and 19q as predictors of survival in oligodendrogliomas, astrocytomas, and mixed oligoastrocytomas. J Clin Oncol18:636–6452000
van den BentMJDubbinkHJSansonMvan der Lee-HaarlooCRHegiMJeukenJW: MGMT promoter methylation is prognostic but not predictive for outcome to adjuvant PCV chemotherapy in anaplastic oligodendroglial tumors: a report from EORTC Brain Tumor Group Study 26951. J Clin Oncol27:5881–58862009