Postoperative radiotherapy for glioblastoma multiforme.

Between July 1983 and December 1990, 39 patients with pathologically documented glioblastoma multiforme were treated with radiotherapy after biopsy (5 patients) or resection (34 patients). There were 30 males and 9 females ranging in age from 9 to 68 years (median 52). All but one of the 39 patients were treated with 10 MV photons. Whole brain irradiation was delivered through lateral parallel opposed fields for the first 40 Gy, followed by reduced portals to boost the tumor bearing area. The range of tumor dose was 58 to 70 Gy, with a median dose of 64 Gy (33 patients). Treatment was executed at 2 Gy per fraction, 5 days per week for all patients except 2 who received 1.8 Gy per fraction. Eight patients underwent reoperation at least once after radiotherapy due to suspicion of recurrence of the disease. No patients were lost to follow-up: 35 patients had died and 4 were still alive. The median survival time was 11.8 months. The 1- and 2-year survival rates were 49% and 12% respectively. A prognostic factor analysis shows that treatment response and the pre-irradiation Karnofsky status were statistically significant variables influencing survival. The median survival was 28.7 months for patients with complete response, compared with 9.8 months for those with partial response or stable disease (p = 0.002). The median survivals were 13.5 and 9.0 months in high (> or = 70%) and low Karnofsky performance scale (p = 0.04). Smaller tumors, a larger extent of resection, reoperation and younger age were favorable factors with borderline significance.(ABSTRACT TRUNCATED AT 250 WORDS)