ABSTRACT
Objective:To evaluate the outcome and prognostic factors of conventional radiotherapy followed by intensity-modulated radiation therapy (IMRT) as a boost combined with chemotherapy in the treatment of high-grade gliomas (HGG). Methods:From Nov. 2004 to Nov. 2006, 112 HGG patients were treated with conventional radiotherapy followed by IMRT as a boost combined with chemotherapy. The radiotherapy regimen included first-course conventional radiotherapy and latE-course IMRT as a boost with the total radiation dosage of 57.5- 62.5Gy (27-29 fractions in 37-45 days). All the patients received chemotherapy. Sixty-three patients received temozolomidE-based chemotherapy and 49 patients received semustine plus teniposide chemotherapy. The treatment reaction was recorded. The overall survival rate and local progression-free survival rate were calculated. The prognostic factors were analyzed by using multivariate COX regression model. Results:The acute treatment toxicity was the most at grade 1 to grade 2 and no grade 4 adverse reaction was observed. Three cases had late radiation-induced brain necrosis. The overall 1-, 2-, and 3-year survival rates were 78.9%, 54.7%, and 30.8%, respectively. Multivariate analysis revealed that tumor location (P=0.001) and KPS score (P=0.011) were independent prognostic factors. The 1-, 2-, 3-year local progression-free survival rates were 63.8%, 38.9%, and 10.5%, respectively. Multivariate analysis revealed that tumor location (P=0.001), KPS score (P=0.001), and histologic type (P=0.005) were independent prognostic factors. Multivariate analysis did not reveal the significant correlation of temozolomide chemotherapy with the prognosis of the patients. Conclusion:Postoperative conventional radiotherapy followed by IMRT as a boost combined with chemotherapy has better short-term efficacy in the treatment of HGG and the adverse reaction is tolerable. KPS score, tumor location, and histologic type are important prognostic factors. Temozolomide chemotherapy is not associated with the prognosis of patients.
ABSTRACT
Purpose:To evaluate the physical dose distributions and tolerance in locally recurrent nasopharyngeal carcinoma treated with intensity modulated radiation therapy (IMRT).Methods:From June 1999 to August 2000, 10 patients with locally recurrent nasopharyngeal carcinoma proven by histology, without neck lymphoid node recurrence and distant metastasis, were treated by IMRT. The interval from the time of initial radiotherapy to recurrence ranged from 14—50(median 25) months. The initial radiotherapy in all patients were treated with external radiotherapy alone to a median dose of 69Gy/35fractions/52days. IMRT method was performed by means of the MIMiC collimator and inverse treatment planning system (NOMOS company, USA). The prescribed dose of re radiotherapy to target volume was 57Gy/19fractions/4weeks.Results:All patients, except for some patients with mild weight loss and reaction in the oral cavity during radiotherapy, tolerated this IMRT well. IMRT achieved the better immediate responses in 10 patients with complete response in 6 cases and partial response in 4 cases. Recurrence was found in two patients, lung distant metastasis in one patient. The median survival in the 10 patients was 14 months. The median planning target volume (PTV) was 95.8(60—134) cm 3. The dose distributions in the PTV were as follows: median average dose 59.65?2.47Gy, median homogeneity index (HI): 1.18(?0.06); median dose to 95% PTV ≥ 53.2 (?1.36)Gy. The median dose to the organs at risk (OAR) were as follows: spinal cord 9.46?5.23Gy; brain stem 20.24?3.55Gy; left parotid gland 18.53?5.30Gy, right parotid gland 19.68?6.21Gy; left lens 2.11?0.65Gy, right lens 2.94?0.57Gy;Chiasm12.34Gy; left optical nerve13.14 Gy, right optical nerve17.65 Gy.Conclusions:Better dose distributions treated with IMRT was achieved in the patients with locally recurrent nasopharyngeal carcinoma and the patients tolerated this radiotherapy well. [