ESTRO 37 Abstract book

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ESTRO 37

Results Fourteen patients were identified as severe pulmonary dysfunction. Of 14 patients, twelve of primary lung cancer and two of solitary metastatic lung tumor, FEV1.0 ranged 560 -1310ml, and FEV1.0% ranged 31 -46%. They were treated with CIRT of 54-60 Gy (RBE) in four fractions. Median follow up was 13 months (3.3 – 16.5 months). Two patients started home oxygen therapy after CIRT. One was considered because of chronic obstructive pulmonary disease progression and the other, who had undergone right pneumonectomy and left upper segmentectomy, was temporary started oxygen therapy after the event of pulmonary infection. Grade 3 or more adverse event, including dermatitis, esophagitis and pneumonitis, was not observed. Changes of performance status were not observed before and after treatment. As for local control, only one case of primary lung cancer developed local recurrence 11months after CIRT. Conclusion CIRT was well tolerated in a patient with severe pulmonary dysfunction and also possesses the possibility of curative treatment. EP-1386 Impact of the stereotactic irradiation schedule for non-small-cell lung carcinoma stage I L. Duvergé 1 , P. Bondiau 2 , J. Bellec 1 , R. Corre 3 , C. Ricordel 3 , B. De Latour 4 , J. Doyen 2 , R. De Crevoisier 1 , E. Chajon 1 , J. Castelli 1 1 Centre Eugène Marquis, radiotherapy, Rennes CEDEX, France 2 Centre Antoine Lacassagne, Radiotherapy, Nice, France 3 Centre Hospitalier Universitaire, Pneumology, Rennes, France 4 Centre Hospitalier Universitaire, Thoracic surgery, Rennes, France Purpose or Objective The objectives of the study were to determine the impact on local control and overall survival of a continuous versus discontinuous irradiation (1 day out of 2) in case of stereotactic irradiation (SBRT) in a non-small cell lung carcinoma (NSCLC) stage I. Material and Methods 198 consecutive patients treated in 2 centers between January 2007 and September 2016 by SBRT for a stage I NSCLC were retrospectively included. The prescribed dose ranged from 48 to 60 Gy in 3 to 6 fractions (median BED = 150 Gy). Treatments were delivered on a standard LINAC (Elekta Synergy or Versa HD) or a robotic radiosurgery system (Accuray Cyberknife) using a respiratory correlated image guidance. Based on the ratio between the duration of treatment and the number of fractions, patients were divided into 2 groups: continuous (ratio <2) or discontinuous (ratio ≥ 2). Overall survival (OS), local control (LC) and toxicity data were collected. Results The median follow-up of the cohort was 34 months. The median age was 73 years old. 158 patients were treated according to the continuous schedule and 40 according to the discontinuous schedule. The two groups were comparable on the main confounding factors (age, T stage, gender, histology). No clinical or treatment- related parameters were correlated with local control. The 2-year LC was 100% for the discontinuous group) versus 91% for the continuous group (p = 0.13). Regarding overall survival, the irradiation schedule and age were the only significant parameters in multivariate analysis. The 2-year OS for patients treated with discontinuous schedule was 77% compared to 65% for continuous schedule (p = 0.035). For the population under 73 years old, 2-year OS for patients treated with discontinuous schedule was 100% compared to 72% for continuous schedule (p = 0.029) while no significant difference was found for the group upper 73 years old (fugure 1). There was less than 3% of acute grade 3 pulmonary

age was 49 ys ,with KPS >90. 12 pts presented myasthenia gravis at diagnosis, at the onset all patients were treated by surgery .Thymic epithelial tumours were staged according to the Masaoka-Koga staging system, 8/17 pts were stage B3,6/17 pts were stage B2, 2/17 was B1, 1/14 was stage AB. Relapses in pleural regions were detected by CT in 100% pts, and PET-CT in 82% pts. 53% pts were treated with somatostatin analogue and all pts received corticosteroid . 53 lesions were treated with SABR. SBRT was delivered by 6MV Linac using beam modulator (ELEKTA S ynergy S)equipped with 4 mm MLC, through two coplanar arcs with VMAT optimization. Median GTV volume was 8.8 cc (2-173 cc). The prescription dose was 30Gy/3fx , 26 Gy /1fx , 24 Gy/3fx to the 80% isodose, in 42/53, 4/53,7/53 lesions respectively. Set-up and isocenter position was controlled before each fx using CBCT .The response was evaluated 60 days after SBRT by CT and PET scan and every 4 months successively. Toxicity was assessed by CTCAE score. Results All pts and 50/53 lesions have been evaluated for response. Median FU is 6.5 (range6-45) months the mean survival is 42.09 months(median not reached), with median progression free survival of 12.91 months.All Pts are still alive and all lesions treated are in complete response. 10/17 pts had relapses outside of treatment sites, these recurrences were treated by SABR. Only grade 2 pneumonitis occurred in 1 pts , who underwent to SBRT for three ipsilateral pleural lesions simulataneously. Conclusion All pts and 50/53 lesions have been evaluated for response. Median FU is 6.5 (range6-45) months the mean survival is 42.09 months(median not reached), with median progression free survival of 12.91 months.All Pts are still alive and all lesions treated are in complete response. 10/17 pts had relapses outside of treatment sites, these recurrences were treated by SABR. Only grade 2 pneumonitis occurred in 1 pts , who underwent to SBRT for three ipsilateral pleural lesions simulataneously. EP-1385 Carbon-ion radiotherapy for peripheral lung tumors in patients with severe pulmonary dysfunction. K. Terashima 1 , K. Matsumoto 2 , A. Matsunobu 3 , H. Suefuji 1 , M. Shinoto 1 , S. Toyama 1 , Y. Shioyama 1 1 SAGA HIMAT Foundation, Radiation Oncology Ion Beam Therapy Center, Tosu, Japan 2 Kyushu University Beppu Hospital, Department of Radiology, Beppu, Japan 3 Fukuoka University Hospital, Department of Radiology, Fukuoka, Japan Purpose or Objective Treatment of lung tumors for patients with severe pulmonary dysfunction is challenging. Carbon-ion radiotherapy (CIRT) possesses possibility to be one of the curative modalities for lung tumor with less irradiated volume of normal lung compared to stereotactic radiotherapy. In this study, we retrospectively analyzed safety and effectiveness of CIRT for peripheral lung tumors in patients with severe pulmonary dysfunction. Material and Methods Between April 2014 and December 2016, total of 115 peripheral lung tumors, including primary lung tumors and solitary metastatic lung tumors, were treated with CIRT. Of these patients, those who were severely impaired pulmonary function, which was defined as forced expiratory volume in one second (FEV1.0) < 1000ml or forced expiratory volume in 1 second as percent of FVC (FEV1.0%) < 50% in this study, were retrospectively analyzed. Toxicities were evaluated using CTCAE v4.0.