摘要
Purpose: A dose escalation study to determine the recommended dose (RD) with stereotactic body radiation therapy (SBRT) for peripheral T2NOMO non-small cell carcinomas (NSCLC) was conducted. The results of the group with PTV 100 cc are reported in this paper.
Materials and methods: The continual reassessment method (CRM) was used to determine the dose level that patients should be assigned to and to estimate the maximum tolerated dose (MTD). Dose limiting toxicity (DLT) was Grade 3 or higher radiation pneumonitis (RP), and Grade 2 or higher RP was used as a surrogate DLT. The RD was equal to the MID. The dose was prescribed at D-95 of the PTV.
Results: Thirteen patients were accrued. More patients should have been enrolled but we decided not to prolong the study period. No patients experienced Grade 3 RP. Two patients experienced Grade 2 RP at 50 Gy in 4 fractions. The predicted MTD was 50.2 Gy. The posterior probability of the Grade 2 RP frequency over 40% was 5.3% for the dose level of 50 Gy. The RD was determined to be 50 Gy.
Conclusions: The RD was determined to be 50 Gy in 4 fractions in this population. (c) 2016 Elsevier Ireland Ltd. All rights reserved.