title: Metastasis-directed therapy of regional and distant recurrences after curative treatment of prostate cancer: a systematic review of the literature.
abstract: BACKGROUND
  The introduction of novel imaging modalities has increased the detection of oligometastatic prostate cancer (PCa) recurrence, potentially justifying the use of a metastasis-directed therapy (MDT) with surgery or radiotherapy (RT) rather than a systemic approach.
  
  
  OBJECTIVE
  To perform a systematic review of MDT for oligometastatic PCa recurrence.
  
  
  METHODS
  This systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We searched the Medline and Embase databases from 1946 to February 2014 for studies reporting on biochemical or clinical progression and/or toxicity or complications of MDT (RT or surgery). Reports were excluded if these end points could not be ascertained or separately analysed, or if insufficient details were provided. Methodological quality was assessed using an 18-item validated quality appraisal tool for case series.
  
  
  RESULTS
  Fifteen single-arm case series reporting on a total of 450 patients met the inclusion criteria. Seven studies were considered of acceptable quality. Oligometastatic PCa recurrence was diagnosed with positron emission tomography with coregistered computed tomography in most of the patients (98%). Nodal, bone, and visceral metastases were treated in 78%, 21%, and 1%, respectively. Patients were treated with either RT (66%) or lymph node dissection (LND) (34%). Adjuvant androgen deprivation was given in 61% of patients (n=275). In the case of nodal metastases, prophylactic nodal irradiation was administered in 49% of patients (n=172). Overall, 51% of patients were progression free 1-3 yr after salvage MDT, with most of them receiving adjuvant treatment. For RT, grade 2 toxicity was observed in 8.5% of patients, with one case of grade 3 toxicity. In the case of LND, 11% and 12% of grade 2 and grade 3 complications, respectively, were reported.
  
  
  CONCLUSIONS
  MDT is a promising approach for oligometastatic PCa recurrence, but the low level of evidence generated by small case series does not allow extrapolation to a standard of care.
  
  
  RESULTS
  We performed a systematic review to assess complications and outcomes of treating oligometastatic prostate cancer recurrence with surgery or radiotherapy. We concluded that although this approach is promising, it requires validation in randomised controlled trials.
authors.affiliation: Department of Radiation Oncology and Experimental Cancer Research, Ghent University Hospital, Ghent, Belgium. Electronic address: piet.ost@ugent.be.
authors.forename: Piet
authors.initials: P
authors.lastname: Ost
authors.affiliation: Department of Radiation Oncology, Institut Gustave Roussy, Villejuif, France.
authors.forename: Alberto
authors.initials: A
authors.lastname: Bossi
authors.affiliation: Department of Urology, Ghent University Hospital, Ghent, Belgium.
authors.forename: Karel
authors.initials: K
authors.lastname: Decaestecker
authors.affiliation: Department of Radiation Oncology and Experimental Cancer Research, Ghent University Hospital, Ghent, Belgium.
authors.forename: Gert
authors.initials: G
authors.lastname: De Meerleer
authors.affiliation: Department of Experimental and Clinical Medical Sciences, Urology Unit, University of Udine, Udine, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Giannarini
authors.affiliation: Department of Urology, Mayo Clinic, Rochester, MN, USA.
authors.forename: R Jeffrey
authors.initials: RJ
authors.lastname: Karnes
authors.affiliation: Department of Radiation Oncology, University of California at San Francisco Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA.
authors.forename: Mack
authors.initials: M
authors.lastname: Roach
authors.affiliation: Division of Oncology/Unit of Urology (URI), IRCCS Ospedale San Raffaele, Milan, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Briganti
mesh_terms: D000726:Androgen Antagonists / Q000627:therapeutic use; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant / Q000379:methods*; D006801:Humans; D008197:Lymph Node Excision / Q000379:methods*; D008297:Male; D009362:Neoplasm Metastasis / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000532:radiotherapy / Q000628:therapy*; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000628:therapy; D049268:Positron-Emission Tomography; D011471:Prostatic Neoplasms / Q000150:complications* / Q000532:radiotherapy / Q000601:surgery; D012008:Recurrence; D016879:Salvage Therapy / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D000726:Androgen Antagonists; D018931:Antineoplastic Agents, Hormonal
keywords: Lymph node excision; Neoplasm metastasis; Neoplasm recurrence; Prostatic neoplasms; Radiosurgery