Brain metastases (BM) frequently develop in patients with
melanoma and are associated with a poor prognosis. Whole brain
radiation therapy (WBRT) is a standard intervention for intracranial disease, particularly in patients with multiple BM.
Ipilimumab improves survival in patients with advanced
melanoma. The purpose of this study is to investigate the safety and efficacy of concurrent WBRT and
ipilimumab. A retrospective analysis was conducted of 13 consecutive patients treated with WBRT within 30 days of
ipilimumab administration. Radiographic response, as measured by serial magnetic resonance imaging scans post-treatment, was graded by modified World Health Organization (mWHO) and immune-related response criteria (irRC) in the 9 patients with follow-up imaging. Treatment-related toxicity was prospectively assessed during treatment. Four of nine patients (44 %) experienced partial response or stable central nervous system (
CNS) disease as measured by mWHO criteria. This number increased to 5 patients (56 %) when irRC criteria were used. Rates of treatment-related neurologic toxicity were low with only one patient experiencing grade 3-4 neurologic toxicity. There was a high rate of intratumoral
hemorrhage in this patient population, with 10 of 10 patients with post-treatment imaging demonstrating new or increased intratumoral
bleeding after WBRT. This retrospective study demonstrates that the primary pattern of CNS response to WBRT and
ipilimumab is stable disease and not regression of BM. Furthermore, while the combination of WBRT and
ipilimumab may offer promising efficacy, prospective studies are needed to further assess efficacy and toxicity.