The Treatment Options of Recurred Brain Metastasis after Prophylactic Cranial Irradiation in Patients with Small-Cell Lung Cancer

ABSTRACT Background Even after prophylactic cranial irradiation (PCI), many small-cell lung cancer (SCLC) patients succumb to brain metastasis. Brain metastasis after PCI is an unsolved issue in SCLC in terms of its dismal prognosis and the limitation of further treatment options. Regarding the treatment option, it is not determined whether re-whole brain radiotherapy (re-WBRT) is safe or gamma-knife surgery (GKS) has its role in SCLC. We investigated which treatment option could be recommended as the up-front therapy to improve survival for SCLC patients with brain metastasis who were previously treated with PCI. Methods The medical records were reviewed for SCLC patients who experienced brain metastases after receiving PCI from 2000 to 2010. We compared overall survival according to the modality of up-front therapy. Overall survival was determined as time from brain metastasis to death due to any cause. Results In total, 245 patients had received PCI in a state of limited disease (n = 204) or extensive disease status (n = 41). Among them, 47 (19.2%) experienced brain metastases: 16.7% (34/204) in LD and 31.7% (13/41) in ED. At the time when brain metastasis developed, extracrainal disease was also on progressing state in 19 patients (40.4%). The modality of up-front therapy for brain metastasis was as follows: 17 (36.1%) got GKS, 14(29.8%) re-WBRT, 7 (14.9%) up-front chemotherapy without local therapy, and 9 (19.1%) did not receive any further treatment. The median overall survival after brain metastasis was 4.9 months. Among 31 patients who received GKS or re-WBRT, 10 patients received at least one subsequent chemotherapy in their lifetime after GKS (6/17, 35.3%) or re-WBRT (4/14, 28.6%). The median survival of GKS, re-WBRT and chemotherapy was 14.3, 3.9 and 6.0 months (P = 0.24), which showed the tendency favoring for up-front GKS. Although it failed to meet statistical significance. Conclusions The up-front GKS showed longer survival in patients who experienced brain metastasis after PCI for SCLC, compared with re-WBRT or chemotherapy only. However, the number of participants was too small to get confirmatory results requiring a prospective therapy to demonstrate the role of GKS in this setting.