The efficacy of high-grade glioma postoperative IMRT based on MRI-guiding target delineation

Objective: To analyze the efficacy and prognostic factors of postoperative radiotherapy for high grade gliomas based on MRI guided target delineation. Methods: Retrospective analysis was conducted on 111 patients with high-grade gliomas from October 2010 to December 2015. The patients were treated with IMRT in combination with temozolomide guided by MRI-CT fusion technique after target delineation at preoperation, postoperation (< 72 h) and before radiotherapy. The survival rate was calculated by K-M method. The analyses of single factor and multiple factor, ranging from the patients' age, gender, pathological grade, number of lesions, multiple lobes, tumour crossing the midline, epilepsy, the maximum diameter of the lesions, adjuvant chemotherapy and other factors on prognosis were conducted with Log-Rank test and COX regression analysis. Results: A total of 111 patients met the criteria for admission, and the overall follow-up rate was 94.6%. The survival rates of 1-, 2-, 3-, 4-, 5- year were 81.6%, 54.2%, 39.1%, 25.4%, 15.5%, respectively. The median survival time was 38 months. The single factor analysis showed that pathological grading (χ² = 5.549, P < 0.05), age (χ² = 6.393, P < 0.05), preoperative tumor maximum diameter (χ² = 4.555, P < 0.05) and adjuvant chemotherapy (χ² = 4.965, P < 0.05) were correlated with on the survival rate, while multivariate analysis showed that pathological grade Ⅲ, younger age, preoperative tumor with size smaller contributed to the good prognosis(Wald = 4.784, 4.560, 5.859, P < 0.05). Conclusions: High grade gliomas after operation by MRI-CT fusion technique in preoperative and postoperative 72 h and MRI before radiotherapy guided by radiotherapy, for intensity-modulated radiotherapy combined with temozolomide chemotherapy, can obtain better efficacy. The grade Ⅲ of glioma, < 50 years old, the maximum diameter of the tumor < 6 cm, the adjuvant chemotherapy may have the better prognosis. (authors)