Radiosurgery appears to be effective in terms of providing local tumor control at the resection cavity following resection of a brain metastasis, and in the treatment of synchronous and metachronous tumors. These data suggest that radiosurgery can be used to prevent recurrence following gross-total resection of a brain metastasis.

✓ Although it is uncommon, pediatric brain abscess remains a serious, life-threatening neurological problem. Those with congenital heart disease, an ongoing infection, or an immunocompromised state are particularly at risk. The symptoms on presentation may include those associated with a space-occupying lesion in the brain, and neuroimaging has made the diagnosis of brain abscess more reliable. Prompt diagnosis and treatment are required to lessen neurological morbidity and the risk of death. Treatment includes medical management with appropriate and specific antimicrobials. Although the effectiveness of medical management has improved and some children may be treated with antimicrobial therapy alone, surgical evaluation remains an important component of the treatment algorithm for most pediatric patients.

Trigeminal neuralgia is uncommon in young adults. Patients tend to present with symptoms similar to those in adults: long periods of pain and venous compression, but outcome unfortunately is not as good as that reported in the older population.

BACKGROUND: Circadian cell-cycle progression causes fluctuating radiosensitivity in many tissues, which could affect clinical outcomes. The purpose of this study was to determine whether outcomes of single-session gamma knife radiosurgery (GKRS) for metastatic nonsmall cell lung cancer (NSCLC) differ based on treatment time. METHODS: Fiftyeight patients received GKRS between 10:00 am and 12:30 pm and 39 patients received GKRS between 12:30 pm and 3:00 pm. The mean peripheral dose was 18.6 Gy. The mean tumor size was 7.3 cm 3 . Magnetic resonance imaging was used to score local control at 3 months. Cause of death (COD) was categorized as central nervous system (CNS)-related or systemic. RESULTS: Demographic and disease characteristics of the 2 groups were similar. Local control at 3 months was achieved in 97% (35/36) of patients who underwent GKRS early in the day versus 67% (8/12) of patients who underwent GKRS later in the day (chi-square, P ¼ .014). Early GKRS was associated with better survival (median 9.5 months) than late GKRS (median 5 months) (Kaplan-Meier log-rank test, P ¼ .025). Factors contributing to better survival in a Cox regression model included early treatment time (P ¼ .004) and recursive partition analysis class (P < .001). Cause of death in the early treatment group was CNS-related in 6% (3/47) of patients versus 24% (8/34) of patients in the late treatment group (chi-square test, P ¼ .026). CONCLUSIONS: GKRS for metastatic NSCLC had better local control, better survival, and a lower rate of CNS-related cause of death when given earlier in the day versus later in the day. These retrospective data should encourage future study in brain radiosurgery and non-CNS stereotactic body radiotherapy series. Cancer 2011;117:414-20.