Value of Adding Boost to Whole Brain Radiotherapy after Surgical Resection of Limited Brain Metastases

Background: Brain metastases are the most common intracranial tumors in adults. Theyaffect 20-40% of all cancer patients. Median survival is one month without treatment,two months with steroids, and three to six months with cranial irradiation. The prognosisof patients with limited (1 or 2) brain metastases appears to be better than that ofpatients with more brain metastases (multiple). Objective: This study was done toevaluate the benefit of adding whole brain radiotherapy (WBRT) boost to 1 or 2 brainmetastases following its resection and WBRT in patients with recursive partitioninganalysis (RPA) class 1 and 2 in comparison to surgical resection and (WBRT). Patientsand Methods: From the period of May 2008 to June 2012, 53 patients with a resectable1 or 2 brain metastases who admitted to the Neurosurgical and Clinical Oncology andNuclear Medicine departments at Mansoura University Mansoura Health InsuranceHospital were randomly assigned prospectively. Patients eligibility: Patients with 1 or 2brain metastases diagnosed by computed tomography (CT) and magnetic resonanceimaging (MRI) with only (RPA) class 1 and 2 were recruited. Further criteria for studyinclusion were resectable metastases measuring 4 cm with no prior WBRT. Patients wererandomly divided into two groups. Group A underwent metastatic surgical resectionfollowed by WBRT using 10 fractions of 3 gray (Gy) each. Group B patients underwentmetastatic surgical resection followed by WBRT plus an additional RT boost to themetastatic site (10 fractions of 3 Gy each plus a boost of 5 fractions of 3 Gy each.Results: The median overall survival (OS) for Group A was 11 months 95%CI (4.919-17.081) while Group B showed a median OS of 17 months 95%CI (11.004-22.996) whichwas statistically insignificant (P=0.45). On multivariate analysis of OS, the treatmentregimen [P .001), the extent of resection (P =.002), and KPS (P .001) were found tomaintain statistical significance. The one year local control (LC) was found in 36% (9patients) in Group A while it was 51.5% (14 patients) in Group B. On multivariateanalysis of LC, both treatment regimen, (P 0.001) and extent of surgical resection (P=.016) maintained statistical significance. Conclusion: After surgical resection oflimited brain metastases. A WBRT boost of 15Gy in addition to 30 Gy of WBRT appearsto improve OS and LC if complete resection has been performed.