原発性肺癌対 定位放射線治療後 肋骨骨折関検討精品课件

Rib fracture after 177 patients with Hiroshi OnishiHiroshi Onishi, , Rihito Tominaga, Marino, Takafumi Komiyama, Kengo University of Yamanashi, stereotactic body stage I non-small Tsuyota Koshiishi, Shinichi Aoki. Kuriyama, Eiichi Sawada, Atsushi Yamanashi, Japan radiotherapy in cell lung cancer Masayuki Araya, Ryo Saito, 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 treatment 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 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 78) 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 Gy 240 Gy 180 Gy 233.3 Gy Prescription D95(PTV) Isocenter D95(PTV) D95(PTV) SBRT planning 1)Instruct patient to reproduce patients self-judged breath-holds according to a respiratory indicator (ABCHES). 2) Measurement of reproducibility of the patients self-inspired breath-hold by 3 times of CT scanning 3)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. 4)Port margin around PTV 5mm in the protocol of 48Gy/4fr 0mm in the protocol of 60Gy/10fr and 70Gy/10fr 5)Beams: 6MV-X ray, non-coplanar multiple (6) static ports or multiple (400 degrees) dynamic arcs 6)Calculation algorithm: Clarkson or Convolution 7)Heterogeneity correction (+) The treatment procedure In every fraction 1) Reassurance of reproducibility of patients self-breath-holds 2) Adjustment of the isocenter of the PTV to the planned position using CT- linac system under patients self-judged breath hold according to a respiratory indicator (ABCHES). 3) Irradiation performed under patients self-breath-holds 4) The tumor position in the irradiation port during irradiation was monitored with a real-time electronic portal imaging device (EPID) 5) The tumor position was verified using CT just after irradiation 【CT】 【Symptom (pain)】 2223366666 1 11 11 1333333333333 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 (-) a. Distance between tumor and chest wall b. Patient characteristics c. CT findings of chest wall d. Maximum dose of the rib Results Positive rib fracture (+):41 cases No 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 / 10 fr / 5-8 days 70 Gy / 10 fr / 5-8 days T1 T2 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 rib fracture Median : 15 months Mean : 16.8 months Cases number Time duration (months) Pain*Fractute (+)(n=41)Fracture (-)(n=46) Grade 027/41(65.9%)39/46(84.8%) Grade 17/41(17.1%)4/46(8.7%) Grade 27/41(17.1%)3/46(7.7%) Grade 30/41(0%)0/46(0%) *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 (-) Distance between tumor and chest wall Fracture (+)(n=41)Fracture(-)(n=46) Age Mean 76.9 (64-89) Mean78.5 (61-91) Gender male: female 24 : 1736 : 10 p 30Gy 2mL of rib received 40Gy not demonstrated not demonstrated not demonstrated 9 (21.4%) 5 (8.3%) 7 (10.3%) 1 (3 %) 2 (5 %) 4 (8.9%) Fractions number No. of patients 42 60 68 30 40 45 54-60 21-60 45 24 - 37.5 30 45 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 th