Early pain relief and toxicity after image-guided VMAT for spinal cord compression Fog, L S1 , Iovane, V1 , Hemer, M1 , Pappot, H1 , Aznar, M C2 , Sjøgren, P1, Appelt, A1,3 1 Dept. of Oncology, Rigshospitalet, University of Copenhagen, Denmark , 2 Nuffield Dept. of Population Health, University of Oxford, UK , 3 Inst. of Cancer and Pathology, St James’s University Hospital, Leeds, UK Introduction We present preliminary data from a prospective study investigating early pain relief and toxicity in patients with malignant spinal cord compression (SCC). Results Worst pain was significantly reduced on days 9 and 13 (3.36, n=11, p=0.01; 3.18, n=17, p=0.007) (figure 2) compared to baseline (5.62) as well as average pain on days 7,9, 13 and 20 (2.52, n=22, p=0.03; 1.96, n=11, p=0.03; 1.72, n=18, p=0.01; 2.64, n=14, p=0.02) compared to baseline (3.55). Tiredness was significantly greater only on day 9 (3.07 vs 2.10, n=9, p= 0.03). Three patients had increased diarrhea in week 2 or 3; these had SCC at the level of Th9 or below (Th9 and L1; L1-3; Th5 and Th11). Six patients reported increased constipation in week 2 or 3. Patients reported an average of 1.8 “other symptoms”. These were oral or throat pain and difficulty in swallowing (11 pts, all of for whom the most cranially treated vertebrae were Th8 or above) (figure 3), others were bone pain (7), dizziness (2) and 12 symptoms experienced by only one patient. Materials and methods 30 consecutive SCC patients treated with 10x3 Gy at our clinic were included (figure 1). Radiotherapy (RT) was delivered as image-guided volumetric modulated arc therapy (VMAT), with sparing of intestines for patients treated at abdomen and pelvis. The patients answered the modified Brief Pain Inventory (mBPI) and Edmonton Symptom Assessment Scale (ESAS) daily on weekdays for three weeks and the EORTC-QLQ-C30 questionnaire weekly for 7 weeks, both from the start of RT. Daily data on worst pain, average pain, tiredness and “other symptoms” were compared to baseline scores using the Wilcoxon signed rank test. Change in diarrhea and constipation from week 1 was recorded. One patient was excluded from analysis due to a change in fractionation. Conclusion Reduction in pain is not observed until the second week of treatment for most patients treated with RT for SCC, and not necessarily maintained after end of treatment. Patients experience multiple early toxicities – particularly oral or throat pain, difficulty in swallowing, and diarrhea, which may all be treatment related. All patients for whom the most cranially treated vertebra was Th8 or above experienced oral or throat pain and difficulty in swallowing. Figure 1. Planning CT for patient no. 1 in this work. Figure 2. Changes relative to baseline of ”worst pain”. The error bars indicate the standard deviation. Figure 3. Treated vertebra versus patient number. A solid circle indicates that the patient experienced DOG (Dysphagia, Odynophagia and Globulus), a cross that the patient did not. The patients are listed in order of when they experienced DOG. Lotte.fog@regionh.dk