Abstract 1784
Background
Radiationtherapy (RT) provide pain reduction in about 60% of patients with painful bone metastases. Studies have identified demographic and clinical characteristics to predict RT response, but no model is clinical useful. Tumor characteristics and inflammation can influence cancer induced bone pain, but the association with RT response are not studied. We test if tumor characteristics and the inflammation marker CRP improve prediction of RT response.
Methods
We included adult patients receiving RT for painful bone metastases in a multicenter, multinational longitudinal observational study. The primary endpoint was analgesic response within 8 weeks after RT defined according to current guidelines. Seventeen independent potential predictor variables assessed at baseline included patient demographics, RT administration, pain characteristics and treatment, cancer diagnosis, tumor characteristics, depression and inflammation (CRP). Multivariate logistic regression analysis with multiple imputation of missing data were applied to identify predictors of RT response. Results are reported as odds ratios (OR) and 95% confidence intervals (CI).
Results
565 eligible patients were enrolled, 424 patients (75%) had complete data on the variables of interest and multiple imputation allowed the final regression models to be carried out on 513 patients (91%). 232 patients (41%, CI 37%-45%) responded to RT. Higher Karnofsky performance status (OR 1.45, CI 1.21-1.73), breast cancer (OR 2.61, CI 1.20-5.69) and prostate cancer (OR 2.64, CI 1.24-5.63) (compared to GI cancer), presence of soft tissue expansion (OR 1.78, CI 1.13-2.81) and higher maximum pain intensity at the radiated site (OR 1.1, CI 1.00-1.21) were significant predictors of positive RT response, while the use of steroids was a negative predictor (OR 0.62, CI 0.42-0.93). The discriminative ability of the model was moderate, with C-statistics 0.70.
Conclusions
This study supports previous findings that higher performance status, cancer diagnosis and higher baseline pain intensity predict analgesic RT response. The study presents new data showing that presence of soft tissue expansion predicts RT response and that CRP is not significantly associated with analgesic RT response.
Clinical trial identification
NCT02107664 (Date of registration April 8, 2014).
Editorial acknowledgement
Legal entity responsible for the study
Pål Klepstad.
Funding
The European Palliative Care Research Centre (PRC).
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
3157 - Efficacy and safety of anlotinib in advanced leiomyosarcoma: Subgroup analysis of a phase IIB trial (ALTER0203)
Presenter: Yihebali Chi
Session: Poster Display session 1
Resources:
Abstract
3710 - The effect of treatment line on the efficacy of Anlotinib hydrochloride in advanced alveolar soft part sarcoma patients
Presenter: Zhiwei Fang
Session: Poster Display session 1
Resources:
Abstract
3184 - Prior exposure to pazopanib (PAZ) did not minor efficacy of regorafenib (REG) in non-adipocytic soft tissue sarcoma patients (pts)
Presenter: Nicolas Penel
Session: Poster Display session 1
Resources:
Abstract
798 - Pexidartinib (Pex) for locally advanced tenosynovial giant cell tumor (TGCT): characterization of hepatic adverse reactions (ARs)
Presenter: Sebastian Bauer
Session: Poster Display session 1
Resources:
Abstract
6117 - VEGFR2 and ITGA polymorphisms as novel pan-sarcoma biomarkers for sensitivity prediction as well as toxicity prevention anti-angiogenesis therapy in pediatric and young adult
Presenter: Qiyuan Bao
Session: Poster Display session 1
Resources:
Abstract
5450 - Reversion of resistance to mTOR inhibitors with the addition of exemestane in patients with malignant PEComa.
Presenter: Roberta Sanfilippo
Session: Poster Display session 1
Resources:
Abstract
4279 - Efficacy and Safety of VEGFR2 Inhibitor Apatinib combined with chemotherapy for Sarcoma in Stage IV
Presenter: Zhiwu Ren
Session: Poster Display session 1
Resources:
Abstract
5929 - Outcomes of metastatic soft tissue sarcoma treated with Pazopanib from dedicated medical oncology sarcoma clinic: A holistic care approach from a developing country
Presenter: Akhil Kapoor
Session: Poster Display session 1
Resources:
Abstract
2469 - Inhibition of mTOR signaling enhances Trabectedin activity in Soft Tissue Sarcoma
Presenter: David Moura
Session: Poster Display session 1
Resources:
Abstract
4210 - Efficacy and safety of apatinib for advanced gastrointestinal stromal tumors after failure of imatinib and sunitinib: An open-label, multicenter, single-arm, phase II trial
Presenter: Zhaolun Cai
Session: Poster Display session 1
Resources:
Abstract