ESTRO 37 Abstract book

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ESTRO 37

1 Leiden University Medical Center LUMC, Radiotherapy / Centre of Expertise Palliative Care, Leiden, The Netherlands 2 Radboud University Medical Center, Radiotherapy, Nijmegen, The Netherlands 3 University Medical Center Utrecht, Julius Center BioStatistics, Utrecht, The Netherlands 4 University Medical Center Utrecht, Radiotherapy,Utrecht, The Netherlands 5 MAASTRO, Radiotherapy, Maastricht, The Netherlands 6 Netherlands Cancer Institute NKI / AvL, Radiotherapy, Amsterdam, The Netherlands 7 University Medical Center Groningen, Medical Oncology / Centre of Expertise Palliative Care, Groningen, The Netherlands 8 University Medical Center Utrecht, Medical Oncology / Centre of Expertise Palliative Care, Utrecht, The Netherlands Purpose or Objective About 30% of advanced cancer patients treated with radiotherapy for painful bone metastases experience a transient aggravation of pain after radiotherapy, the so- called pain flare (PF). Previously, a Canadian placebo- controlled randomized study showed that five daily 8 mg doses of dexamethasone reduced the incidence of PF from 35% to 26% (p= 0.05, Chow, Lancet Oncol 2016). The aim of our study was to compare two different schedules of dexamethasone versus placebo to prevent the occurrence of PF after radiotherapy for painful bone metastases. Material and Methods We performed a double-blind, randomised, placebo- controlled trial, including patients from 12 out of 21 Dutch radiotherapy centres. Patients were treated with a single fraction of 8 Gy (80%) or 20-24 Gy in 5-6 fractions (20%). They were randomly allocated to receive: A- placebo at least 1 hr before start of treatment (day 1) and then every day for 3 days afterwards, B- 8 mg dexamethasone (day 1) followed by 3 days of placebo, or C- four daily 8 mg doses of dexamethasone (days 1-4). We included patients with uncomplicated painful bone metastases from solid tumors. Patients reported worst pain scores and opioid analgesic intake before treatment and daily for 14 days after (start of) radiation treatment, and on day 28 using the brief pain inventory (BPI). They completed the European Organisation for Research and Treatment of Cancer (EORTC) quality of life QLQ-C15- PAL, and the bone metastases module (BM22) at baseline, and at day 8, 15 and 28. PF was defined as at least a two- point increase on a scale of 0 to 10 in the worst pain score with no decrease in analgesic intake, or, a 25% or greater increase in analgesic intake with no decrease in the worst pain score from days 0–14, followed by a return to baseline levels or below. Primary analysis of incidence of PF was by intention-to-treat (ITT) with patients with missing primary data classified as having PF. We also performed sensitivity analyses (SA) with missings classified as having no PF. Results From Jan 2012 to Apr 2016, 295 patients were randomized. PF incidence was 50% (ITT) or 25% (SA) for A, 34% or 16% for B, and 44% or 25% for C (ITT; p= 0.06 and SA; p= 0.15, Table 1). Although B had the lowest incidence of PF, a relatively high percentage did not return to baseline pain levels, preventing them from complying to the PF criterion and instead indicating pain progression. In those patients who experienced a PF, four daily doses of dexamethasone postponed the occurrence of PF (A: 88% on day 1-5 and 12% on day 6-14; B 73% and 27%; and, C 52% and 48%). In C, patients reported lower pain scores on day 2-5 (Figure 1). Toxicity and quality of life outcomes will be presented at ESTRO 37.

Conclusion There was no significant effect of dexamethasone on the incidence of PF after palliative radiotherapy for painful bone metastases. In patients receiving four doses of dexamethasone mean pain scores were lower on day 2-5 after start of radiotherapy, and, the occurrence of PF was postponed. OC-0389 Pain education of patients with painful bone metastases reduces pain; a multicentre randomised trial J. Geerling 1 , Y. Van der Linden 2 , V. Mul 3 , E. De Nijs 4 , M. Oudhof 5 , N. Raijmakers 6 , G. De Bock 7 , A. De Graeff 8 , A. Reyners 1 1 UMCG, CCC- palliative team, Groningen, The Netherlands 2 LUMC, radiotherapy department, Leiden, The Netherlands 3 UMCG, CCC radiotherapy department, Groningen, The Netherlands 4 LUMC, palliative team, Leiden, The Netherlands 5 UMCU, radiotherapy department, Utrecht, The Netherlands 6 IKNL, IKNL, Utrecht, The Netherlands 7 UMCG, Epidemiology, Groningen, The Netherlands 8 UMCU, Medical oncology, Utrecht, The Netherlands Purpose or Objective Radiotherapy (RT) is an effective palliative tre atment for painful bone metastases, with over 70% responders, although pain is not always sufficiently controlled. Analyses from the Dutch Bone Metastasis Study on 1157 patients showed that during weekly follow up 35% of the patients reported a pain intensity of ≥ 5 on a numeric rating scale (range 0-10 (NRS)), despite pain medication. Pain management education may improve patient empowerment and, consequently, reduce pain intensity. The effect of nurse-led education (NLE) in patients undergoing RT for painful bone metastases was