3-D conformal radiotherapy with concomitant and adjuvant temozolomide for patients with glioblastoma multiforme and evaluation of prognostic factors

BACKGROUND: The aim of the retrospective study was to evaluate the outcome and prognostic factors of newly diagnosed glioblastoma patients who received 3-D conformal radiotherapy (RT) combined with concomitant and/or adjuvant temozalamide (TMZ) postoperatively. PATIENTS AND METHODS: Fifty patients with glioblastoma multiforme were treated with 3-D conformal RT combined with concomitant and/or adjuvant TMZ postoperatively. Median age was 57 years (range, 12–79) and median Karnofsky performance status (KPS) was 70 (range, 40–100). A multivariate Cox regression model was used to test the effect of age, sex, KPS, extent of surgery, tumour dimension (<5cm vs. ≥5cm), full dose RT (≥60 Gy vs. <60 Gy), concurrent TMZ and adjuvant TMZ treatment (adjuvant therapy plus 6 cycles of TMZ group versus <6 cycles of TMZ group) on the overall survival. RESULTS: The median follow up time was 10 months (range 3–42). One- and 2-year overall survival rates were 46% and 20%, respectively. The prognostic factors important for the overall survival were a full dose RT (≥60 Gy) (p=0.005) and the application of adjuvant TMZ for 6 cycles (p=0.009). CONCLUSIONS: The results of our study confirm the efficiency of RT plus concomitant and adjuvant TMZ, with an acceptable toxicity in patients. We suggest that at least 6 cycles of adjuvant TMZ should be administered to obtain a benefit from the adjuvant treatment.