title: Re-irradiation for painful bone metastases: evidence-based approach.
abstract: The prognosis of patients with bone metastases has improved with the advent of increasingly effective systemic treatment and better supportive care. A growing number of bone metastases patients now outlive the duration of benefits from their initial treatment of radiotherapy (RT) while some patients fail to initially respond to RT. As such, re-irradiation (re-RT) may be required. The current review updates the literature on findings in the area of re-RT. In particular, the recent publication of the National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) Symptom Control (SC20) trial shows that an 8 Gy treatment in a single fraction for re-RT is non-inferior and less toxic than 20 Gy in multiple fractions. Furthermore, patients responding to re-RT have experienced superior quality of life (QoL) and complain of less functional interference from pain; this provides a strong case in support of bone metastases patients being offered re-treatment. However, despite such findings, some specific patients will never respond to initial radiation or re-RT. New evidence suggests significant differences in bone markers between responders and non-responders, thus opening the possibility for further research into the use of such biomarkers for predicting prognosis and for the guidance of consequent treatment decisions.
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Chiu
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Leonard
authors.initials: L
authors.lastname: Chiu
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Marko
authors.initials: M
authors.lastname: Popovic
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Carlo
authors.initials: C
authors.lastname: DeAngelis
authors.affiliation: Department of Radiation Oncology, Blanchard Valley Regional Cancer Center, Findlay, Ohio, USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Lutz
authors.affiliation: Department of Radiation Oncology, Liaoning Cancer Hospital & Institute, Shenyang 110042, China.
authors.forename: Na
authors.initials: N
authors.lastname: Zhang
authors.affiliation: The Cancer Institute of the State of São Paulo (ICESP) - Faculty of Medicine of the University of São Paulo, São Paulo, Brazil; Department of Radiation Oncology, Hospital Sírio-Libanês, São Paulo, Brazil.
authors.forename: Gustavo Nader
authors.initials: GN
authors.lastname: Marta
authors.affiliation: The Cancer Institute of the State of São Paulo (ICESP) - Faculty of Medicine of the University of São Paulo, São Paulo, Brazil.
authors.forename: Lucas Castro
authors.initials: LC
authors.lastname: Mendez
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Breanne
authors.initials: B
authors.lastname: Lechner
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Natalie
authors.initials: N
authors.lastname: Pulenzas
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Milica
authors.initials: M
authors.lastname: Milakovic
authors.affiliation: Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, ON, Canada.
authors.forename: Ronald
authors.initials: R
authors.lastname: Chow
authors.affiliation: Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, Canada. Edward.Chow@sunnybrook.ca.
authors.forename: Edward
authors.initials: E
authors.lastname: Chow
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D001859:Bone Neoplasms / Q000532:radiotherapy* / Q000556:secondary; D016723:Bone Remodeling / Q000528:radiation effects; D019583:Dose Fractionation, Radiation; D019317:Evidence-Based Medicine; D006801:Humans; D015337:Multicenter Studies as Topic; D010146:Pain / Q000532:radiotherapy*; D010166:Palliative Care / Q000379:methods*; D011379:Prognosis; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic; D000069475:Re-Irradiation / Q000379:methods*; D019233:Retreatment / Q000379:methods
chemical_list: D015415:Biomarkers
keywords: Re-irradiation (re-RT); bone metastases