ESTRO 37 Abstract book

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ESTRO 37

Results Median age for patient at the time of the first decision to treat a site with 8 Gy single fraction was 67 years. 71% of patients had reached the survival end point at the time of data collection. Median overall survival for the cohort was 786 days (26.2 months). Median site-specific survival since first radiation was 214.5 days (7.2 months). Of the irradiated sites, 33.8% were metastases from a breast primary. Most common histology was adenocarcinoma (68.2%). Data indicating response to treatment was available for 127 sites, of which 82.7% reported to have achieved good subjective symptomatic control. 28 of 154 (18.2%) sites were re-radiated, either due to poor primary response, or symptom relapse. No adverse events were reported after re-irradiation. Conclusion 8 Gy single fraction radiotherapy to bone metastases is a cost-effective treatment, which leads to good results in terms of symptom control and quality of life. EP-1658 A scoring system to predict bone metastasis after radical resection of colorectal cancer L. Käsmann 1 , A. Li 2 , D. Rades 1 , C. Fu 2 1 University of Lübeck, Department of Radiation Oncology, Lubeck, Germany 2 Changhai Hospital- The Second Military Medical University, Department of Colorectal Surgery, Shanghai, China Purpose or Objective Colorectal cancer is the third most common type of cancer and the fourth leading cause of cancer-related death in the world. The development of bone metastasis is a severe burden for patients´ prognosis and quality of life. The aim of this study is to develop a scoring system to predict bone metastasis after radical resection within 5 years to identify patients at risk for continuous monitoring and optimize surveillance. Material and Methods We evaluated the patient records of 1,749 patients treated during 2001-2010 at one cancer center. 50 patients developed bone metastasis within 5 years after treatment. Univariate and multivariate analysis were performed to find the risk factors (age, gender, localization, histology, preoperative carbohydrate antigen 199 (CA-199) level, T-stage, lymph node metastasis and pulmonary metastasis) using Chi square test and logistic regression. Results Univariate analysis showed tumor site (P=0.026), preoperative carbohydrate antigen 199 (CA199) level (P=0.039), lymph node metastasis (P<0.001) and pulmonary metastasis(P<0.001) were significantly associated with the development of bone metastasis. On multivariate analysis three factors, namely rectal cancer (p=0.038), lymph node metastasis (p=0.006) and pulmonary metastasis (p<0.001) were identified as independent risk factors of metachronous bone metastasis of colorectal cancer within 5 years. Scoring was conducted by adding zero or one point from each variable and resulted in four groups of 0, 1, 2 or 3 points. Three groups were formed, with 0-1 points vs. 2 points vs. 3 points (1.5% vs. 6.6% and 10.5%, p<0.001). Conclusion This new score can help physicians to identify patients at risk for continuous monitoring and optimize surveillance management for patients to detect and treat bone metastasis very early in order to avoid the occurrence of skeletal complications.

EP-1659 Superficial Hyperthermia+Radiotherapy: toxicity and outcome of 65 metastatic lesions G. Cattari 1 , A. Di Dia 2 , M. Gatti 1 , E. Delmastro 1 , G. Belli 1 , A. Salatino 1 , P. Gabriele 1 1 FPO-IRCCS Candiolo, Radiotherapy, Candiolo, Italy 2 FPO-IRCCS Candiolo, Medical Physics, Candiolo, Italy Purpose or Objective The association of superficial hyperthermia and radiotherapy (RT-HT) improves the clinical outcome and quality of life in patients with symptomatic lesions. In our Institute we perform superficial HT to offer an other treatment choice to advanced oncological diseases previously or not irradiated. We need to evaluate the safety, feasibility and toxicity of RT-HT association in superficial recurrent and metastatic tumors in this cohort of patients Material and Methods 42 patients (pts) (mean age 69 years; range: 47-95) with superficial recurrent/metastatic tumors were treated: 19 breast carcinoma, 11 head&neck cancer, 3 malignant melanoma, 4 sarcomas, 1 uterine adenocarcinoma, 1 hepatocarcinoma, 2 pancreatic carcinoma and 1 small cell cancer of thigh. The total number of treated lesions was 65. The mean Karnofsky Index value is 80. Pretreated pts (73%) received a mean radiotherapy dose of 50 Gy. Pts underwent radiotherapy treatment using 3D- conformal radiotherapy (17/42), Arc-Therapy (2/42) or Helical Tomotherapy (23/42). External beam radiotherapy was delivered in 5-30 fractions of 1.7-5 Gy to a total dose of 20-63 Gy (mean external dose: 40.3 Gy). HT is performed with a double electromagnetic superficial applicators operating at the frequency of 434 MHz. HT session was delivered once/twice weekly during the time of external radiotherapy, 1-2 hours after radiotherapy. Average, maximum and minimum temperature parameters were recorded during hyperthermia treatment. The treatment goal was to reach 40- 42°C in > 90% (T90) of measured points for a duration of 60 minutes. Acute and late toxicity was evaluated according to the CTCAE criteria. Local control was assessed after the end of the treatment on the basis of the RECIST Criteria Results During hyperthermia treatment the median temperature [range] reached was 40.5 °C [39 – 42.9°C]. 5 pts interrupted the treatment: 2 pts (5%) for G3 toxicity, 2 (5%) for poor compliance and 1 (2,4%) for clinical progression disease. 2 pts (5%) had acute cutaneous toxicity ≥ G3 at 1 month. 4 pt had toxicity > G2 at 3 months, three had > G2 at 6 months and only one patients at 12 months. No pts showed toxicity ≥ G2 thereafter. The mean follow-up was 13 months (range 1- 50 months). The Local control rate was: 88%, 78%, 68% ,61%, 71% and 75% at 1 , 3 , 6 , 12, 24, 36 months respectively. The time to local progression was ranged between 1 and 36 months (mean:8 months). The detailed results are reported in Table 1. 10 pts are dead (9 for disease and one for vascular accident. Univariate analysis showed that Tmean, Tmax, Tmin, T90 parameters were not associated with local control rate Conclusion RT-HT is useful combined treatment with a good local control rate and patient compliance. The clinical outcome and the time duration of the follow-up is affected by the advanced stage of diseases. A larger pool and a more detailed patient stratification are needed to evaluate the outcome data in the time