ESTRO 37 Abstract book

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ESTRO 37

survival rate of 77% for all groups. All 10 local recurrences occurred inside PTV70 volume. From the 24 deaths, 11 were due to distant metastases, 3 grade 5 toxicity, 2 from local progression, 8 non-cancer deaths. Local control and survival were significantly better in WHO grade III patients (p = 0.000 and p = 0.032 respectively). On multivariate analysis, age of 52 years (sig. 0.017) and distant metastases had greatest impact on survival (sig 0.000). Xerostomia was the most frequent late toxicity 55% (n=60), but no patient had grade > 2. Hypothyroidism requiring hormonal reposition occurred in 15,5% (n=17) with no other hormonal deficit. With a mean cochlear dose of 49Gy, Grade 3 hearing loss happened in 8% (n=9) and peripheral neuropathy in 4,5% (n=5). One patient developed Grade 2 renal toxicity, 1 had asymptomatic temporal lobe necrosis and other had skull base osteoradionecrosis requiring hyperbaric oxygen therapy. Unfortunately, only 60 patients (55%) had EBV (serum EBNA and serum viral copies) studies pre treatment. Although 36 (60%) had titles above 599, no difference in metastasis-free survival or overall survival (p = 0,430) on this subgroup.

Oncology in 2002, as one of the first medical centers in Germany to do so, there have been over 2000 patients treated. This study is going to analyze the distribution of treated diseases and its development over the last 15 years regarding the different types of SRTs, fractionated SRT (FSRT) and radiosurgery, and the overall survival. Material and Methods About 2100 cases (1700 patients) were treated with cerebral SRT between 2002 and 2016. On the basis of the patients’ records patient data were collected and entered into the newly created research database of the department. The data consisted of: primary and treatment diagnosis, previous or parallel therapies (e.g. surgery, chemotherapy), imaging and radiotherapy parameters. Results The analysis is ongoing and currently 1505 (72% 1505/2100) cases are analyzed with a median age of 60 years (range 6 – 94 years). Of all, 518 (45.0%) were male, 632 (55.0%) female. We categorized all RTs according to diagnosis: malign, benign, metastasis or tumors of uncertain malignant potential. Figure 1 shows the distribution and its development over the last 15 years. In total, 849 SRTs for metastases, 410 for benign tumors, 212 for malignant tumors, and 34 for tumors of uncertain behavior were performed. For all patients, median follow-up was 9.8 months (range 0 months - 15.5 years). Separated by the subgroups, follow-up was 79.5 months (range 0 - 186.4 months) for benign tumors, 5.8 months (range 0-182.2 months) for malignant tumors, 9.8 months (range 0 - 186.4 months) for metastases, and 44.0 months (range 0 - 181.8 months) for tumors of uncertain behavior. The median overall survival (OS) was 32.5 months (95% CI: 20.4 - 44.6 months) for all patients, for metastases 8.0 months (95% CI: 6.6 - 9.5 months), for malign tumors 12.4 months (95% CI: 10.0 - 14.8 months). The mean OS of the benign tumors was 161.5 months (95% CI: 155.6 - 167.3 months) and for tumors of uncertain malignancy 163.4 months (95% CI: 144.0 - 182.9 months). Figure 2 displays OS allocated regarding RT types.

Fig. 1

Conclusion As our data matured, our results confirm excellent local and regional control of concurrent chemoradiation in the IMRT era with acceptable late toxicity, comparable to others in the literature. Distant metastases are a challenge and desperately need more strategies to help these patients. stereotactic radiotherapy at the Klinikum rechts der Isar, Munich A.A. Schmidt 1 , K.A. Kessel 1 , M.N. Duma 1 , S.E. Combs 1,2 1 Technical University of Munich TUM, Department of Radiation Oncology, Munich, Germany Purpose or Objective Stereotactic radiotherapy (SRT) is a high precision treatment for several benign and malign tumor entities. Especially regarding target volumes in the brain and head/neck area the accurate radiation dosage is of utmost importance to preserve healthy tissue. Since the implementation of SRT at the department of Radiation EP-1177 15 years of cerebral 2 Helmholtz Zentrum, Institute of Innovative Radiotherapy iRT, Neuherberg, Germany

Fig. 2