Effectiveness of temozolomide treatment used at the same time with radiotherapy and adjuvant temozolomide; concomitant therapy of glioblastoma multiforme: multivariate analysis and other prognostic factors.

AIM: Prognostic factors which affect treatment results of glioblastoma multiforme (GBM; WHO Grade IV) patients has been investigated in many researches. For these patients determination of prognostic factors helps generating multimodal therapy protocols. For this purpose, in the Baskent University Medical School, Neurosurgery Clinic, Adana Medical Research Center, specific characteristics of GBM patients who have surgery retrospectively investigated and factors which affect prognosis has been determined.
METHODS: Between January 2005 and January 2009, 59 patients (25 female, 34 male) who have GBM have been evaluated retrospectively. Mean follow-up period was 27.4 (+/-17.3) months. Headache (66.1%) was the most seen symptom. Time of diagnosis was 1-2 months for most of the patients (54.2%). Fifty-nine patients had 67 operations totally. Preoperative Karnofski Performance Scale (KPS) was >or=70 for 43 operations, <or=70 for 24 operations. Frontal lobe was the most involved part of the tumor,and biggest tumor has the diameter of 4.8 (+/-1.42) cm. Forty gross total resection, 26 subtotal resection and 1 lobectomy were performed. Postoperatively for 41 operations KPS>or=70, for 26 operations KPS<or=70. After surgery 44 patients had radiation therapy (RT). Eighteen patients had only adjuvant RT, 26 patients had temozolomide (TMZ) treatment used at the same time with RT combination therapy (CombT with TMZ) and 6 cures adjuvant TMZ concomitant therapy (ConcT with TMZ). Median survival and prognostic factors of 42 GBM patients was calculated with multivariable and univariable analysis.
RESULTS: Median survival was 8 (+/-1.5) months for patients who died. One year survival was 83.3% and two-year survival 16.7%. After treatment, relapse occurred in 12 patient at the site of the tumor and these patients had been reoperated. After univariate statistical analysis preoperative KPS was >or=70 (P=0.0000) , postoperative KPS 2 was >or=70 (P=0.0000), type of tumor resection (P=0.00002), multiple operations (P=0.001), adjuvant RT (P=0.0000) and ConcT with adjuvant TMZ (P=0.0000) were all positive prognostic factors which extend the survival. After multivariate analysis, post operative KPS was >or=70 (P=0.003; OR:0.89; % 95 CI:0.83-0.96), type of resection (P=0.055; OR:0.37; % 95 CI:0.13-0.12) and multiple operations (P=0.042; OR:2.65; % 95 CI:1.03-6.82) were independent prognostic factors.
CONCLUSION: When independent prognostic factors were examined ,median survival found out 7.8 months longer fort he patients whose postoperative KPS were >or=70, 5.7 months longer for the patients who had radical resection, 6.6 months longer for the patients who had multiple operations. Although patients who had ConcT with adjuvant TMZ had 1.7 months longer survival compared to patients who had only adjuvant RT, it was not determined as an independent prognostic factor.