| 脑部放疗,上午比下午敏感许多! 5 |, K2 n! }; ~  P, v
 , `( U* I. {- \9 C- U* ~( w4 g( Y: M: n
 Cancer 2011 Jan 15;117(2):414-20. doi: 10.1002/cncr.25423. Epub 2010 Sep 9.9 B$ `: T+ |2 Z. n8 v+ D" T- H4 [
 Gamma knife radiosurgery for brain metastasis of nonsmall cell lung cancer: is there a difference in outcome between morning and afternoon treatment?
 4 n. ^) f( s; P5 E0 {Rahn DA 3rd, Ray DK, Schlesinger DJ, Steiner L, Sheehan JP, O'Quigley JM, Rich T.9 ^7 N1 ]" ~& {. V1 g. C
 SourceDepartment of Radiation Oncology, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908, USA." f! o( }! X" d4 Y% h
 
 : e8 `/ K# _- K6 n$ Y- z" @# EAbstract9 ~1 D$ q! F; B" N& q
 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.
 * H& w( _8 L: [/ V& D& q& G. D0 j& H& D1 `
 METHODS: Fifty-eight 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 cm³. 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.! V( F( a* ^+ V! ?1 I! f
 8 A7 `* Z, V0 t! l
 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 = .014). Early GKRS was associated with better survival (median 9.5 months) than late GKRS (median 5 months) (Kaplan-Meier log-rank test, P = .025). Factors contributing to better survival in a Cox regression model included early treatment time (P = .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 = .026).# i3 {/ _$ }; n0 \2 h
 % r5 s. c- A9 l0 l
 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.
 J! t8 ^' ]$ M8 e) X
 $ W' z" A1 c8 M1 S0 n& G
 |