ESTRO 36 Abstract Book

S730 ESTRO 36 2017 _______________________________________________________________________________________________

analysis, age ≧ 75 was a significant prognostic factor for OS (P=0.015). Cervical lymph node metastasis was a significant prognostic factor for PFS (P=0.006). LC had no significant prognostic factor. In 17 patients without lymph node metastases or lung metastases, concurrent chemoradiation with taxane was a significant prognostic factor for PFS (P=0.018). Conclusion Multimodality therapies including radiation therapy were effective. EP-1378 The Role of Radiation Therapy in the Treatment of Hemangiopericytoma/ Solitary Fibrous Tumor Y.Y. Chiang 1 1 Chang Gung Memorial Hospital, Proton and Radiation Therapy Center, Taoyuan City, Taiwan Purpose or Objective Hemangiopericytoma (HPC)/ Solitary fibrous tumors (SFTs) ㄅ are rare soft-tissue tumors of mesenchymal origin, and originate in a variety of anatomical locations. There is little consensus regarding the role of radiotherapy. Here is a review of treatment approach and clinical outcome from a tertiary referral hospital. Material and Methods Retrospective analysis was performed. Patients evaluated at Chang Gung Memorial Hospital with diagnosis of hemangiopericytoma/ solitary fibrous tumor between 1996 and 2015 were identified. Patient records were reviewed to collect data on demographics, tumor characteristics, treatment modalities, survival, and length of follow-up. The extent of surgery, tumor diameter, radiation dose and techinique were recoded. Patterns of failure were recoreded. Local control rate were determined by recurrences after initial surgery or radiotherapy. Patients who had surgery were compared with patients who underwent preoperative or postoperative RT or RT alone. Results We identified 42 patients with diagnosis of SFT/HPC. Thirty-five patients were avalible for clinical data and follow up information. Out of 35 patients, 20 (57%) were female and 15 (43%) were male, with a median age of 46.8 years (range, 21-76). Anatomical locations included intracranial 10(29%) and extracranial 25(71%) (head & neck 6, thorax 5, spine 4, pelvis 1, extremities 5, orbit 4). Among 34 patients who received surgery at our institution, 27(80%) paitents achieved gross total resection(GTR) and 7(20%) received subtotal resection(STR). The other one patients received palliative chemotherapy at our institution. There are 13 patients who received RT: 5 in adjuvant setting with initial postoperative RT , 7 in salvage setting, and 1 palliative setting. Doses ranged from 40-66 Gy with 2 Gy per fraction, and one of the patient receiving 16 Gy SRS. RT techinique included IMRT (7), VMAT (3), 3D conformal (1), electron beamRT(1). Median follow-up time is 73 months (range, 4-252 months).Thirty one (89%) patients were alive, and 4(11%) patients were dead. Five and 10 years OS were 95.7%, and 82.2%, respectively.Recurrence occurred in 10 patients ( 29%), 6 locally, 1 distantly and 3 both locally and distantly. Of 10 patients who experienced recurrences, 9 of the cases were intracranial HPC, and 1 were of head & neck origin. Local recurrence occurred in 9 of the pts (26%): 4 after surgery, 5 after surgery and postoperative RT. LC rate at 3 and 5 years were 89.8% and 68.4% respectively. For the group of pts who receive surgery only with comparison to surgery and RT, the 5-year of LC and OS were 74.2%, 64.8%(p=.56), and 90.9%, 100%(p=.73).For the group of pts who receive GTR with comparison to STR, the 5-year of LC and OS were 68.6%, 45.7% (P=.31) and 100%, 100% (p=0). Conclusion

Median follow up was 65 months. We observed 16 local failures, transferring into a 5-year-LC rate of 69%. Median time to onset of a local recurrence was 18 months (6-60 months). LC was significantly influenced by disease situation (primary vs recurrent), T stage and use of additional chemotherapy in univariate analysis. Distant failures were found in 21 patients, resulting in a 5-year- DC rate of 65%. Median time to onset of distant failure was 17 months (3-52 months). Gender, age and type of surgery were significantly associated with DC in univariate analysis. Actuarial 5-year rates of FFTF and OS were 44% and 76%, respectively. While FFTF was only influenced by use of CHT, OS was significantly associated with type of surgery and timing of EBRT in univariate analysis. However, according to multivariate analysis none of the mentioned factors remained significant for any endpoint. Secondary amputations were needed in 9 patients (13%). Good functional outcome was achieved in 72%. Conclusion Combination of IOERT and EBRT achieves high local control rates and good overall survival with encouraging rates of preserved limb function even after R1- resections. However, results are worse compared to R0-resections indicating that even IOERT and EBRT cannot fully compensate an unfavourable surgical outcome. Multivariate analysis failed to identify further prognostic factors. H. Ihara 1 , K. Katsui 1 , K. Hisazumi 2 , S. Sugiyama 2 , K. Watanabe 2 , T. Waki 3 , T. Kaji 4 , N. Katayama 2 , M. Takemoto 5 , O. Yamasaki 4 , K. Iwatsuki 4 , S. Kanazawa 2 1 Okayama University Graduate School of Medicine- Dentistry and Pharmaceutical Sciences, Department of Proton Beam Therapy, Okayama, Japan 2 Okayama University Hospital, Department of Radiology, Okayama, Japan 3 Tsuyama Chuo Hospital, Department of Radiology, Tsuyama, Japan 4 Okayama University Graduate School of Medicine- Dentistry and Pharmaceutical Sciences, Department of Dermatology, Okayama, Japan 5 Japanese Red Cross Society Himeji Hospital, Department of Radiology, Himeji, Japan Purpose or Objective To retrospectively analyze the treatment results of angiosarcoma of the scalp. Material and Methods This study included 22 patients (15 men, 7 women; median age 78.5 years, range 34 – 91 years) with angiosarcoma of the scalp and who received radical radiation therapy between January 2000 and July 2016 at our institution. Four patients had cervical lymph node metastases. One patient had only one lung metastasis. The median radiation dose was 70Gy (range, 52–70), and the fractional dose was 2Gy. Radiation therapy alone or a combination of surgery, radiation therapy, chemotherapy and immunotherapy were administered. Taxane (paclitaxel and/or docetaxel) was used in 17 patients. Concurrent chemoradiation with taxane was administered in 14 patients. The overall survival (OS), progression-free survival (PFS) and local control (LC) rates were calculated using Kaplan-Meier analysis. Univariate analyses of various potential prognostic factors for OS rate, PFS rate, and LC rate were performed. Results The median follow-up period was 14.5 months (range, 3.0– 102.0). Local recurrence occurred in 6 patients. Distant recurrence was observed in 13 patients. OS rate was 78% at 1 year, 36% at 3 years. PFS rate was 38% at 1 year, 31% at 3 years. LC rate was 72% at 1 year, 62% at 3 years. One patient could not achieve the planned radiation therapy because of grade 3 dermatitis and delirium. In univariate EP-1377 Single institutional experience of the treatment of angiosarcoma of the scalp