ESTRO 37 Abstract book

S917

ESTRO 37

September 2017. 12 patients had a lactate ≥ 4mmolL -1 , 72 patients had a lactate between 2mmolL -1 and 4 mmolL -1 and 305 patients had a lactate < 2mmolL -1 . Mean lactate was 1.2 mmolL -1 , 2.7 mmolL -1 and 6.3 mmolL -1 in each of the respective groups. Baseline characteristics were similar between study populations. Mortality at 7-days and 30 days significantly increased across groups (30 days; 15.3% versus 26.4% versus 66.7%, 7-day; 3.9% versus 12.5% versus 50.0%, admission lactate, < 2mmolL -1 versus between 2mmolL -1 and 4 mmolL -1 versus ≥ 4mmolL -1 ; p < 0.05 for all between group comparisons). Conclusion Hyperlactaemia appears to be a marker of poor prognosis in cancer patients presenting with sepsis. Further analysis of lactate measurement for risk stratification is required. EP-1707 An insight into Bone health in cancer survivors from a developing nation A. Sharma 1 , M. Sharma 2 , M. Upadhyay 1 , M. Surya 3 , S. Sharma 3 , R. Seam 1 1 Indira Gandhi Medical college, Department of Radiotherapy & Oncology, Shimla, India 2 Kamla Nehru Hospital- Indira Gandhi Medical college, Department of Obstetrics & Gynecology, Shimla, India 3 Indira Gandhi Medical college, Department of Radiodiagnosis, Shimla, India Purpose or Objective Cancer and its treatments can have profound effects on bone health. The purpose of our study was evaluated incidence and factors associated with impaired bone health in cancer survivors. Material and Methods A total of 140 cancer survivors enrolled in prospective study evaluating bone health were included. Fracture risk of was evaluated by dual-energy x-ray absorptiometry densitometry (DEXA) scan. Parameters evaluated included T score, Z score, Bone mineral density (BMD) and Bone mineral content (BMC). Risk of fracture was analyzed by age, height, body mass index, weight, type of cancer, treatment by chemotherapy, radiotherapy, hormonal therapy, exercise, performance status and ability to perform house hold activities. Pearson's chi-squared test was use to evaluate factors effecting osteoporosis. A p value of ≤ 0.05 was considered significant. All analyses were performed using the IBM SPSS statistics version 22.0 software package (SPSS Inc., Chicago, IL, USA). Results Median age was 55yrs (range 26-79yrs). The study included 78 patients with gynecological malignancies and 39 patients with breast cancer. Eight six percent received chemotherapy, 87% were subjected to radiotherapy. Median BMI was 23.88 kg/m 2 (16.4-36.4 kg/m 2 ), median weight was 55 Kg(35-83Kg) , median height was 151 cms (131-166cms). Median performance status was 80 (range 60-100). Sixteen percent of the patients routinely enrolled themselves in brisk walking >30minutes per day. T score spine was median -2.7(range 1.3 to -5.9), Z score spine median -1.6(range 1.6 to -4.3), median BMD spine 0.76 (range 0.40-58.05) and median BMC spine was 38.39(range 19.12-69.65). T score femur neck was median -1.9 (range 1.9 to -4.7), Z score femur neck median-0.8 (range 6.0 to -3.2), BMD femur neck median 0.67 (range 0.30-3.8) and median BMC femur neck was 3.13(range 0.83-41.04). Sixty one per cent of cancer survivors had osteoporosis, 30% had osteopenia and 9% had normal bone health. Factors significantly associated

with osteoporosis included weight <50kg (p=0.001), KPS 70 or less (p=0.004), non breast cancer primary

(p=0.021). Conclusion

In the study 91% of patients had impaired bone health. Three out of five survivors had osteoporosis and 1 out of 3 had osteopenia. Factors significantly associated with osteoporosis included weight <50kg, KPS ≤70 and non breast cancer primary. EP-1708 Clinical relevance of DNA-damage response in metastatic breast and lung cancer under irradiation Y. Goy 1 , S. Riethdorf 2 , K. Rothkamm 3 , C. Petersen 1 , A. Krüll 1 , K. Pantel 2 , H. Wikman 2 , K. Borgmann 3 1 University Medical Center Hamburg-Eppendorf, Department of Radiotherapy and Radio-oncology, Hamburg, Germany 2 University Medical Center Hamburg-Eppendorf, Department of Tumor Biology, Hamburg, Germany 3 University Medical Center Hamburg-Eppendorf, Laboratory of Radiobiology & Experimental Radio- oncology, Hamburg, Germany Purpose or Objective Circulating tumor cells (CTCs) represent the first step of the metastatic cascade. In breast and lung cancer, high numbers of CTCs correlate with a more aggressive disease and independently predict progression-free as well as overall survival. The monitoring of CTCs under chemotherapy showed a correlation of persistent CTCs and shorter survival. This indicates stronger defense mechanisms in the remaining CTCs. More efficient DNA repair capacity could contribute to such stronger resistance. The aim of this study is to identify relevant DNA damage response pathways in CTCs and peripheral blood lymphocytes under radiotherapy and their possible implications for the adjustment of future therapies. Material and Methods 87 blood samples of patients with bone/brain metastatic breast/lung cancer (n=19/24) were collected before, at the end of radiotherapy and at the first follow-up. The number of CTCs at the first follow-up was compared with clinical treatment response (e.g. MRI/CT and performance status). Enumeration and characterization of CTCs were done using the CellSearch®system. Apoptosis was measured in CTCs (in vivo irradiation) with the help of the M30 antibody in the CellSearch®system and DNA damage repair analyzed by yH2AX and 53BP1 foci detection was investigated in CTCs (in vivo) and primary lymphocytes ( ex vivo irradiation) to monitor genomic instability and DNA repair capacity of primary as well as tumor derived cells. Results Changes in the number of CTCs under local radiotherapy were observed in 62% of the patients. In breast cancer patient an increase, no change or a clear reduction in the number of CTCs was detected in 8, 42 and 50% of the cases respectively. The impact on systemic effects and survival is under estimation. The few lung cancer patients with detectable CTCs (16% at baseline) showed shorter survival compared to CTC free patients. An increase in the percentage of M30-positive CTCs was only observed in a subgroup of patients. Also the DNA repair capacity after ex vivo irradiation of primary lymphocytes indicates differences in the analyzed patient cohort. Conclusion The results indicate that monitoring DNA repair in CTCs and primary lymphocytes under radiotherapy is already showing excellent potential for judging treatment