title: Imaging response during therapy with radium-223 for castration-resistant prostate cancer with bone metastases-analysis of an international multicenter database.
abstract: The imaging response to radium-223 therapy is at present poorly described. We aimed to describe the imaging response to radium-223 treatment.
  
  
  
  We retrospectively evaluated the computed tomography (CT) and bone scintigraphy response of metastatic castration-resistant prostate cancer (CRPC) patients treated with radium-223, in eight centers in three countries.
  
  
  
  A total of 130 patients were included, the majority (n=84, 65%) received radium-223 post docetaxel. Thirty-four of 99 patients with available data (34%) received concomitant abiraterone or enzalutamide. A total of 54% (n=70) patients completed the planned six injections of radium-223. In patients with available data, a transient increase in bone metastases-related pain was observed in 27% (n=33/124) and an improvement of bone metastases-related pain on treatment with radium-223 was noted in 49% of patients (n=61/124). At 3 and 6 months of treatment with radium-223, bone imaging showed stable disease in 74% (n=84/113) and 94% of patients (n=93/99) with available data, respectively. An increase in the number of bone lesions was documented at 3 months compared with baseline in 26% (n=29/113) and at 6 months compared with 3 months in 6% of patients (n=6/99), respectively. Radiological extraskeletal disease progression occurred in 46% of patients (n=57/124) with available CT data at 3 and/or 6 months.
  
  
  
  Progression of bone metastases during radium-223 therapy is uncommon. A bone flare (pain and/or radiological) may be noted during the first 3 months, and should not be confused with progression. Imaging by CT scan should be considered after three and six doses of radium-223 to rule out extraskeletal disease progression.
authors.affiliation: Genitourinary Oncology Service, Institute of Oncology, Meir Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: D
authors.initials: D
authors.lastname: Keizman
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
authors.forename: M O
authors.initials: MO
authors.lastname: Fosboel
authors.affiliation: Department of Oncology and Haematology, Kantonsspital St Gallen, St Gallen, Switzerland.|Department of Radiology and Nuclear Medicine, Kantonsspital St Gallen, St Gallen, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Reichegger
authors.affiliation: Department of Oncology, Rambam Medical Center, Haifa, Israel.
authors.forename: A
authors.initials: A
authors.lastname: Peer
authors.affiliation: Department of Oncology, Rabin Medical Center, Petah Tikva, Israel.
authors.forename: E
authors.initials: E
authors.lastname: Rosenbaum
authors.affiliation: Department of Oncology and Haematology, Kantonsspital St Gallen, St Gallen, Switzerland.|Department of Radiology and Nuclear Medicine, Kantonsspital St Gallen, St Gallen, Switzerland.
authors.forename: M-C
authors.initials: MC
authors.lastname: Desax
authors.affiliation: Department of Oncology, Rabin Medical Center, Petah Tikva, Israel.
authors.forename: V
authors.initials: V
authors.lastname: Neiman
authors.affiliation: Department of Oncology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
authors.forename: P M
authors.initials: PM
authors.lastname: Petersen
authors.affiliation: Department of Oncology and Haematology, Kantonsspital St Gallen, St Gallen, Switzerland.|Department of Radiology and Nuclear Medicine, Kantonsspital St Gallen, St Gallen, Switzerland.
authors.forename: J
authors.initials: J
authors.lastname: Mueller
authors.affiliation: Department of Oncology, Kantonsspital Chur, Chur, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Cathomas
authors.affiliation: Genitourinary Oncology Service, Institute of Oncology, Meir Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: M
authors.initials: M
authors.lastname: Gottfried
authors.affiliation: Genitourinary Oncology Service, Institute of Oncology, Meir Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: H
authors.initials: H
authors.lastname: Dresler
authors.affiliation: Department of Oncology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
authors.forename: D
authors.initials: D
authors.lastname: Sarid
authors.affiliation: Department of Oncology, Soroka Medical Center, Beer-Sheva, Israel.
authors.forename: W
authors.initials: W
authors.lastname: Mermershtain
authors.affiliation: Department of Oncology, Soroka Medical Center, Beer-Sheva, Israel.
authors.forename: K
authors.initials: K
authors.lastname: Rouvinov
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
authors.forename: J
authors.initials: J
authors.lastname: Mortensen
authors.affiliation: Department of Oncology and Haematology, Kantonsspital St Gallen, St Gallen, Switzerland.|Department of Radiology and Nuclear Medicine, Kantonsspital St Gallen, St Gallen, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Gillessen
authors.affiliation: Department of Oncology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
authors.forename: G
authors.initials: G
authors.lastname: Daugaard
authors.affiliation: Department of Oncology and Haematology, Kantonsspital St Gallen, St Gallen, Switzerland.|Department of Radiology and Nuclear Medicine, Kantonsspital St Gallen, St Gallen, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Omlin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy* / Q000556:secondary; D006801:Humans; D007610:Kallikreins / Q000097:blood; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D064129:Prostatic Neoplasms, Castration-Resistant / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D019275:Radiopharmaceuticals / Q000627:therapeutic use*; D011883:Radium / Q000627:therapeutic use*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D019275:Radiopharmaceuticals; C000615150:Radium-223; C549870:KLK3 protein, human; D007610:Kallikreins; D017430:Prostate-Specific Antigen; D011883:Radium