Intracranial aneurysms after radiotherapy (RT) have previously been reported. However, the majority of studies were case reports. Therefore, we performed a nationwide study to explore the risk of radiation-induced intracranial aneurysms. This study included patients diagnosed with head and neck cancer (ICD9: 140–149, 161). Intracranial aneurysms formation was identified using the following ICD9 codes: nonruptured cerebral aneurysm (ICD9:4373), aneurysm clipping (ICD9:3951). Patients who did not receive curative treatment and those with intracranial aneurysms before the diagnosis of head and neck cancer were excluded. In total, 70,691 patients were included in the final analysis; they were categorized into the following three groups: nasopharyngeal carcinoma (NPC) with RT, non-NPC with RT, and non-NPC without RT. Patients in the NPC with RT group had the highest risk of developing intracranial aneurysms (hazard ratio (HR) 2.57; P < 0.001). In addition, hypertension was also a risk factor of developing intracranial aneurysms (HR 2.14; P < 0.01). The mean time interval from cancer diagnosis to intracranial aneurysm formation in the NPC with RT group was 4.3 ± 3.1 years. Compared with the non-NPC with RT and the non-NPC without RT groups, patients with NPC who received RT had a higher risk of developing intracranial aneurysms.

Literature regarding cardiac deaths in hemorrhagic stroke patients is few. The aim of this study was to investigate the incidence and risk factors of cardiac death in hemorrhagic stroke patients. We used the multiple causes of death database from the Centers for Disease Control and Prevention Wide-ranging Online Data of the United States. We identified death certificates from 2006 to 2010 with hemorrhagic stroke (International Classification of Disease, Tenth Revision (ICD-10) code I60-62), or ischemic stroke (ICD-10 code I63), and evaluated the frequency and risk factors of reporting MI (ICD-10 code I20-25) or arrhythmias (ICD-10 code I44-45, I47-49) as the main cause of death in these populations. Over the five-year period, 224,359 death certificates that mentioned hemorrhagic stroke were identified, and the cause of death was MI in 8.95% and arrhythmia in 7.28% patients. With autopsy confirmation, the incidences of MI and arrhythmias in the hemorrhagic stroke group were still lower than the ischemic group. The odds ratio of reporting arrhythmias as a cause of death in hospitalized population was higher. A substantial percentage of hemorrhagic stroke patients had cardiac death. Greater efforts are needed to closely monitor high-risk groups such as females and the elderly.

E13588 Background: BM represent a common problem in EGFR-mutated lung adenocarcinoma. The updated Lung-molGPA elucidates the survival in patients with non-small-cell lung cancer and BM by incorporating the effect of EGFR gene alterations. However, the nature history and differences of prognostic implication between common and uncommon EGFR mutations remain unsolved. Methods: By retrospective analysis of Chang-Gung Research Database (CGRD), patients with EGFR-mutated lung adenocarcinoma and BM were included into analysis of PFS and OS. EGFR mutations were categorized into exon 19 deletions (Del19), exon 21 Leu858Arg substitution (L858R) and uncommon mutations. Kaplan-Meier method was used to estimate survival, and multivariate Cox proportional hazard models was performed to estimate adjusted hazard ratios (HR) and 95% confidence interval (CI). The p-value was set to be statistically significant at 0.05 or less. Results: From April 1, 2014 to June 30, 2015, 269 out of 818 patients with EGFR-mutated lung adenocarcinoma and BM were included, of which 115 patients with Del19, 131 patients with L858R, and 23 patients with uncommon EGFR mutations. The baseline characteristics were balanced in age, gender, KPS, ECM, number of BM, and timing of BM. In comparison with those with L858R, uncommon mutations is a poor prognostic factor for PFS (HR 2.24, 95% CI: 1.34-3.75, p = 0.002). The median PFS of Del 19, L858R, and uncommon EGFR mutations were 10.4, 10.0, and 3.2 months, respectively (log-rank p = 0.03). Besides, the median OS of Del 19, L858R, and uncommon EGFR mutations were 18.1, 17.4, and 12.5 months, respectively (log-rank p = 0.05). In comparison with those treated with gefitinib, afatinib treatment is a good prognostic factor for PFS and OS (PFS, HR 0.57, 95% CI: 0.35-0.94, p = 0.03; OS, HR 0.48, 95% CI: 0.26-0.91, p = 0.03). The median PFS of those treated with sequential WBRT, concurrent WBRT and TKI alone were 11.0, 8.5, and 10.3, respectively (log-rank p = 0.63). In addition, the median OS of those treated with sequential WBRT, concurrent WBRT and TKI alone were 18.7, 15.2, and 18.2 months, respectively (log-rank p = 0.50). Conclusions: Among patients with EGFR-mutated adenocarcinoma, common and uncommon EGFR mutations have distinct natural history and prognostic implications in patients with BM.