title: Active surveillance in metastatic renal-cell carcinoma: a prospective, phase 2 trial.
abstract: BACKGROUND
  A subset of patients with metastatic renal-cell carcinoma show indolent growth of metastases. Because of the toxicity and non-curative nature of systemic therapy, some of these patients could benefit from initial active surveillance. We aimed to characterise the time to initiation of systemic therapy in patients with metastatic renal-cell carcinoma under active surveillance.
  
  
  METHODS
  In this prospective phase 2 trial, we enrolled patients with treatment-naive, asymptomatic, metastatic renal-cell carcinoma from five hospitals in the USA, Spain, and the UK. Patients were radiographically assessed at baseline, every 3 months for year 1, every 4 months for year 2, then every 6 months thereafter. Patients continued on observation until initiation of systemic therapy for metastatic renal-cell carcinoma; a decision that was made at the discretion of the treating physician and patient. The primary endpoint of the study was time to initiation of systemic therapy in the per-protocol population. The follow-up of patients is ongoing.
  
  
  RESULTS
  Between Aug 21, 2008, and June 7, 2013, we enrolled 52 patients. Median follow-up of patients in the study was 38·1 months (IQR 29·4-48·9). In the 48 patients included in analysis, median time on surveillance from registration on study until initiation of systemic therapy was 14·9 months (95% CI 10·6-25·0). Multivariate analysis showed that higher numbers of International Metastatic Database Consortium (IMDC) adverse risk factors (p=0·0403) and higher numbers of metastatic disease sites (p=0·0414) were associated with a shorter surveillance period. 22 (46%) patients died during the study period, all from metastatic renal-cell carcinoma.
  
  
  CONCLUSIONS
  A subset of patients with metastatic renal-cell carcinoma can safely undergo surveillance before starting systemic therapy. Additional investigation is required to further define the benefits and risks of this approach.
  
  
  BACKGROUND
  None.
authors: Cleveland Clinic Taussig Cancer Institute, Main Campus, Cleveland, OH, USA. Electronic address: rinib2@ccf.org.
authors: Brian I
authors: BI
authors: Rini
authors: USC Norris Comprehensive Cancer Center, Los Angeles, CA, USA.
authors: Tanya B
authors: TB
authors: Dorff
authors: Cleveland Clinic Taussig Cancer Institute, Main Campus, Cleveland, OH, USA.
authors: Paul
authors: P
authors: Elson
authors: Vall d'Hebron University Hospital and Institute of Oncology, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors: Cristina Suarez
authors: CS
authors: Rodriguez
authors: Cleveland Clinic Taussig Cancer Institute, Main Campus, Cleveland, OH, USA.
authors: Dale
authors: D
authors: Shepard
authors: Cleveland Clinic Taussig Cancer Institute, Main Campus, Cleveland, OH, USA.
authors: Laura
authors: L
authors: Wood
authors: Vall d'Hebron University Hospital and Institute of Oncology, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors: Jordi
authors: J
authors: Humbert
authors: Royal Marsden NHS Foundation Trust, London, UK.
authors: Linda
authors: L
authors: Pyle
authors: Fox Chase Cancer Center, Temple Health, Philadelphia, PA, USA.
authors: Yu-Ning
authors: YN
authors: Wong
authors: Cleveland Clinic Taussig Cancer Institute, Main Campus, Cleveland, OH, USA.
authors: James H
authors: JH
authors: Finke
authors: Cleveland Clinic Taussig Cancer Institute, Main Campus, Cleveland, OH, USA.
authors: Patricia A
authors: PA
authors: Rayman
authors: Royal Marsden NHS Foundation Trust, London, UK.
authors: James M G
authors: JM
authors: Larkin
authors: Cleveland Clinic Taussig Cancer Institute, Main Campus, Cleveland, OH, USA.
authors: Jorge A
authors: JA
authors: Garcia
authors: Fox Chase Cancer Center, Temple Health, Philadelphia, PA, USA.
authors: Elizabeth R
authors: ER
authors: Plimack
mesh_terms: D000368:Aged; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000556:secondary* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009392:Nephrectomy; D011159:Population Surveillance; D011379:Prognosis; D011446:Prospective Studies; D013030:Spain / Q000453:epidemiology; D015996:Survival Rate; D014057:Tomography, X-Ray Computed / Q000379:methods*; D006113:United Kingdom / Q000453:epidemiology; D014481:United States / Q000453:epidemiology