Potential impact of the overall treatment time on outcomes after whole-brain irradiation with 10×3 Gy for brain metastases

Aim: To investigate the impact of the overall treatment time (OTT) of whole-brain irradiation (WBI) with 10×3 Gy on outcomes in patients with brain metastases. Patients and Methods: Seventy-three patients who started WBI on Monday (OTT=12 days, including one weekend without irradiation) were compared to 257 patients who began WBI on Tuesday to Friday (OTT=14 days, including two weekends) for intracerebral control and survival. Seven additional factors were analyzed, including age, gender, Karnofsky performance score (KPS), tumor type, number (N) of brain lesions, extracerebral metastases and interval between cancer diagnosis and WBI. Results: On univariate analysis, age (p=0.039), KPS (p<0.001) and N brain metastases (p=0.006) were associated with intracerebral control; OTT had no significant impact (p=0.20). Age (p<0.001), KPS (p<0.001), N brain metastases (p=0.037) and extracerebral metastases (p<0.001) were associated with survival; OTT had no significant impact (p=0.37). Conclusion: OTT (12 vs. 14 days) had no significant impact on outcomes after WBI with 10×3 Gy.