1、Rib fracture after 177 patients with,Hiroshi Onishi, Rihito Tominaga, Marino, Takafumi Komiyama, KengoUniversity of Yamanashi,stereotactic body stage I non-small,Tsuyota Koshiishi, Shinichi Aoki. Kuriyama, Eiichi Sawada, AtsushiYamanashi, Japan,radiotherapy in cell lung cancer,Masayuki Araya, Ryo Sa
2、ito, Kan Nambu, Naoki Sano, Tsutomu Araki,Background,Despite the increasing popularity of SBRT, experience with extremely hypofractionated, high-dose radiotherapy regimens and their posttreatment radiologic findings and clinical toxicity remains limited. Multiple Phase I and II SBRT studies of the t
3、reatment of Stage I-II NSCLC have reported chest wall (CW) pain and/or rib fracture as a part of the toxicity profile. But an exact frequency of rib fracture after SBRT and risk factors for it was unknown.,Purpose,The aim of the study was to assess the relationship between the background of factors
4、in patients or the treatment and the development of rib fracture*.,* Definition of the rib fracture in the study: A CT findings of linear line indicating fracture on rib on high dose-irradiated area,Total cases Age Stage Tumor diameter Distance to chest wall,177 (male 132, female 45) 55-92 (median 7
5、8) years T1N0M0 118, T2N0M0 59 8-55 (median 25) mm 0-53 (median 6) mm,Patients characteristics,Irradiated from 2001.11 to 2009.4,Dose and prescription,Total dose / fractionations/ days 40Gy / 10 fr / 4-7 days 48 Gy / 4 fr / 4-7 days 60 Gy / 10 fr / 5-8 days 70 Gy / 10 fr / 5-8 days,BED(a/b=3Gy) 93.3
6、 Gy 240 Gy 180 Gy 233.3 Gy,Prescription D95(PTV) Isocenter D95(PTV) D95(PTV),SBRT planning,Instruct patient to reproduce patients self-judged breath-holds according to a respiratory indicator (ABCHES). Measurement of reproducibility of the patients self-inspired breath-hold by 3 times of CT scanning
7、 Three dimensional (3D) treatment planning was performed. Planning target volume (PTV) was defined as gross tumor volume (GTV) + reproducibility of the patients self-breath-hold + 5mm safety margin. Port margin around PTV5mm in the protocol of 48Gy/4fr0mm in the protocol of 60Gy/10fr and 70Gy/10fr B
8、eams: 6MV-X ray, non-coplanar multiple (6) static ports or multiple (400 degrees) dynamic arcs Calculation algorithm: Clarkson or Convolution Heterogeneity correction (+),The treatment procedure In every fraction Reassurance of reproducibility of patients self-breath-holds Adjustment of the isocente
9、r of the PTV to the planned position using CT- linac system under patients self-judged breath hold according to a respiratory indicator (ABCHES). Irradiation performed under patients self-breath-holds The tumor position in the irradiation port during irradiation was monitored with a real-time electr
10、onic portal imaging device (EPID) The tumor position was verified using CT just after irradiation,【CT】【Symptom (pain)】,SBRT,SBRT,Following up examination ( months after SBRT),Analysis,Time duration to detection of rib fracture Clinical symptom (pain) Comparison between cases with fracture (+) versus
11、 (-)a. Distance between tumor and chest wallb. Patient characteristicsc. CT findings of chest wall d. Maximum dose of the rib,Results,Positive rib fracture (+)：41 casesNo rib fracture (-) for more than 24 months until the last follow-up : 46 cases,40Gy / 4 fr / 4-7 days 48 Gy / 4 fr / 4-7 days 60 Gy
12、 / 10 fr / 5-8 days 70 Gy / 10 fr / 5-8 daysT1T2,Fracture (+),Fracture (-),0 / 1 (0.0%) 16 / 37 (43.2%) 14 / 34 (41.2%) 11 / 15 (73.3%) 25 / 61 (41.0%) 16 / 26 (61.5%),1 / 1 (100.0%) 21 / 37 (56.8%) 20 / 34 (58.8%)4 / 15 (26.7%) 36 / 61 (59.0%) 10 / 26 38.5%),Time duration from SRT to detection of r
13、ib fracture,Median : 15 months Mean : 16.8 months,Cases number,Time duration (months),*CTCAE(Common Terminology Criteria for Adverse Events) v3.0,Clinical symptom (pain ),Distance between tumor and chest wall (mm),16mm,Fracture (-),Fracture (+),Comparison between cases with fracture (+) versus (-) D
14、istance between tumor and chest wall, p 0.05 (chi-square test),Comparison between cases with fracture (+) versus (-) Patient characteristics,Comparison between cases with fracture (+) versus (-) CT findings,Case,24月後,86 y.o. female adenoca,T2N0M0 70Gy/10fr,24 months after,Chest wall edema and thinni
15、ng of rib cortex,Rib fracture,Risk factor* for rib fracture,* Stepwise Logistic regression anlysis,Comparison between cases with fracture (+) versus (-) Maximum dose in chest wall ( in 17 cases in which detailed dose was calculated), a/b = 3 Gy,p0.01 t-test,Fracture (+),(BED Gy),Comparison between c
16、ases with fracture (+) versus (-) Maximum chest wall dose (BED),a/b = 3 Gy,Fracture (-),ROC analysis,Chest wall maximum BED225.5Gy Sensiivity 0.71 1-Specificity= 0.11,Sensitivity,(1-specificity),Comparison between cases with fracture (+) versus (-) Maximum chest wall dose (BED),Fracture (-),Fracture
17、 (+),(Gy),225.5Gy,Likelihood ration=sensitivity/ (1-specificity）0.71/0.11=6.45,Comparison between cases with fracture (+) versus (-) Maximum chest wall dose (BED),J. Thorac Oncol 2009:4:1035-37. Int J Radiat Oncol Biol Phys 2010; 76:796-801. Radiotherapy and Oncology 2009;91:360-68. Lung Cancer 2005
18、;48:107-14. Lung Cancer 2008;60:193-9. Lung Cancer 2006;51:97-103.,Author,Total Dose(Gy),High risk factors,Voloney(1)Dunlap(2)Pettersson(3)Zimmermann4) Fritz(5)Nyman(6),33 - 533 513,Distance to chest wall 30Gy2mL of rib received 40Gynot demonstratednot demonstratednot demonstrated,9 (21.4%)5 (8.3%)7
19、 (10.3%)1 (3 %)2 (5 %)4 (8.9%),Fractions number,No. of patients,426068304045,54-6021-604524 - 37.53045,Chest wall complications including rib fracture in previous literatures,Rib fracture,Conclusion,Rib fracture after SBRT for lung cancer was produced in 41 of 177 cases (23.2%). Female and short distance between the tumor and the chest wall were risk factors for production of rib fracture. The distance between the tumor and the chest wall was under 16mm in all rib fracture cases. Maximum BED(a/b=3Gy) of the chest wall in all rib fracture cases was over 200Gy,
