ESTRO 38 Abstract book

S744 ESTRO 38

with various factors like driver mutation status, age, performance status, progression free interval and time since last irradiation influencing the treatment decision. Surgery or focal RT with stereotactic techniques may be an option for patients with oligo‐metastases. However, they might not be a feasible option for patients with multiple BM.We aim to study the impact and outcome of patients with BM from lung cancer receiving WBRT for clinico‐radiological progression. Material and Methods We retrospectively analyzed patients with BM from lung cancer who were registered at Tata Memorial Hospital, Mumbai, India between November 2012 to August 2017 and had undergone two courses of WBRT. Data of patients were retrieved from electronic medical records. Patients were treated using conventional or conformal technique with either tele‐cobalt or Linear accelerator Results Out of 315 patients OF lung cancer, diagnosed and treated with WBRT for BM, 23 received re‐WBRT. There were 12 men and 11 women with median age of 51 years (range 30 to 70yr with adenocarcinoma in 21 patients. Driver mutation status was positive in 65% patients (9 with EGFR and 6 with ALK mutation positive) and a majority of patients (83%) had BM at presentation. Clinico‐radiological progression was the commonest indication of re‐WBRT; only one patient had radiological progression alone. A majority of these patients had developed new symptoms while about 30% had recurrence of previous symptoms. Mean Karnofsky performance score (KPS) prior to re‐WBRT was more than 70 in 13 patients (57%). Mean time interval between the two courses of WBRT were 17.1 months (range 5‐33 months). Most patients received WBRT using a conventional technique (91%) and were treated in a tele‐ cobalt unit (83%).Re‐WBRT fractionation schedule was 25 Gy/10 fractions (n=12, 52%) or 20 Gy/5 fractions (n=10, 44%). Mean biological effective dose (BED 2Gy ) for the first and second courses of WBRT were 63.75 Gy and 57.5 respectively. The average cumulative BED 2Gy was 121 Gy (range 108‐135 Gy). Almost all patients received short acting steroids during the course of re‐WBRT. All patients completed the course of treatment. At the time of analysis, 7 patients were alive; median survival of patients after re‐WBRT was 9 weeks (range 1‐78 weeks). Conclusion In lung cancer patients with symptomatic progression of multiple BM and good prognostic features (driver mutation positive, good performance status and long time interval since last WBRT), re‐WBRT is a safe and feasible option. EP-1363 Stereotactic Ablative Radiotherapy For Lung Cancer In Elderly Patients. A. Revelant 1 , M. Emilio 1 , T. Marco 2 , D.P. Antonino 1 , G. Carlo 1 , F. Giuseppe 1 , P. Elisa 1 , M. Fabio 1 , N. Federico 1 , Z. Umberto 3 , P. Jerry 4 , F. Giovanni 1 1 Centro di Riferimento Oncologico, Radiation Oncology, Aviano, Italy ; 2 Azienda Sanitaria Universitaria Integrata, Radiation Oncology, Udine, Italy ; 3 Azienda Ospedaliera Santa Maria degli Angeli, Pneumology, Pordenone, Italy ; 4 Centro di Riferimento Oncologico, Epidemiology, Aviano, Italy Purpose or Objective According to available evidences, stereotactic ablative radiotherapy (SABR) has been widely analyzed in elderly and appear to have similar benefits to their younger counterpart. However, for the definition of elderly often is used 70 years as threshold (as illustrated in International Society of Geriatric Oncology’s Guidelines). The aim of this study is to demonstrate effectiveness and safety of using SABR in older patients (> 80 years old), with primary lung cancer, comparing the outcome in term of local control (LC), progression‐free survival (PFS) and overall survival (OS) with younger patients at 1, 2 and 3 years. We didn’t use the data at 5 years, because the event death is

peripheral SBRT or conventional radiotherapy were excluded. The SBRT was given as 4‐D VMAT. The 80 Gy/8 F or 50 Gy/5F was dosed centrally. Results From 2012 to 2015 62 patients received 80 Gy and from 2016 to 2017 40 patients received 50 Gy.

Table: Patient characteristics 50

Gy/5G

80

Gy/8F

N=40 73.2 86.4)

N=62

(46.8;

75.9. (50.0; 90.5)

Age (yr.)

Sex

Female

18 (45%) 22 (55%)

35 (56%) 27 (44%)

Male

Performance status 0‐1

20(50%) 12 (30%)

32 (52%) 22 (36%) 8 (13%)

2 3

8 (20%)

FEV1% of predicted

59% (21‐117%) 66% (22‐123%)

Stage (TNM7) I

15 (27.5%)

17 (27%)

II

22 (55%)

35 (56.5%)

III‐IV

2(7.5%)

10 (16%)

Histology

Squamous

cell.

19 (47.5%)

22 (35%)

carcinoma

Adenocarcinoma Other histology

18 (45%)

24 (39%) 12 (19%) 4 (6.5%)

2(5%)

Unknown

1 (2.5%)

Figure: Overall survival

The median overall survival was 20.5 mo. in the 80 Gy group and 21.7 mo. in 50 Gy/5 (p=ns). The median cancer related survival was 59.7 mo. and not reached, respectively (p=ns). Conclusion No difference was observed between the schedule groups in neither overall survival nor cancer specific survival. EP-1362 Re-Irradiation Of Whole Brain For Symptomatic Progression In Lung Cancer Patients J.P. Agarwal 1 , S. Karmakar 1 , N. Mummudi 1 , A. Tibdewal 1 1 Tata Memorial Hospital HBNI, Department of Radiotherapy, Mumbai, India Purpose or Objective Whole brain radiation therapy (WBRT) is an effective palliative measure and provides durable symptom relief in lung cancer patients with multiple brain metastases (BM). Clinico‐radiological progression of BM after WBRT is a common and challenging scenario; treatment is tailored,