title: Reporting practices of pharmacodynamic studies involving invasive research procedures in cancer trials.
abstract: BACKGROUND
  Tumour biopsy for pharmacodynamic (PD) study is increasingly common in early-phase cancer trials. As they are non-diagnostic, the ethical justification for such procedures rests on their knowledge value. On the premise that knowledge value is related to reporting practices and outcome diversity, we assessed in a sample of recent invasive PD studies within cancer trials.
  
  
  METHODS
  We assessed reporting practices and outcomes for PD studies in a convenience sample of cancer trials published from 2000 to 2010 that employed invasive, non-diagnostic tissue procurement. Extracted data were used to measure outcome reporting in individual trials. Using a reporting scale we developed for exploratory purposes, we tested whether reporting varied with study characteristics, such as funding source or drug novelty.
  
  
  RESULTS
  Reporting varied widely within and across studies. Some practices were sporadically reported, including results of all planned tests (78% trials reporting), use of blinded histopathological assessment (43% trials reporting), biopsy dimensions (38% trials reporting), and description of patient flow through PD analysis (62%). Pharmacodynamic analysis as a primary end point and mandatory biopsy had statistically significant positive relationships with overall quality of reporting. A preponderance of positive results (61% of the studies described positive PD results) suggests possible publication bias.
  
  
  CONCLUSIONS
  Our results highlight the need for PD-reporting guidelines, and suggest several avenues for improving the risk/benefit for studies involving invasive, non-diagnostic tissue procurement.
authors.affiliation: Biomedical Ethics Unit, Division of Experimental Medicine, Department of Medicine, McGill University, Montreal, Qubec, Canada.
authors.forename: G A
authors.initials: GA
authors.lastname: Freeman
authors.forename: J
authors.initials: J
authors.lastname: Kimmelman
authors.forename: J
authors.initials: J
authors.lastname: Dancey
authors.forename: J G
authors.initials: JG
authors.lastname: Monzon
mesh_terms: D014408:Biomarkers, Tumor; D001706:Biopsy / Q000941:ethics / Q000706:statistics & numerical data*; D002986:Clinical Trials as Topic / Q000941:ethics / Q000706:statistics & numerical data*; D017321:Clinical Trials, Phase I as Topic / Q000941:ethics / Q000706:statistics & numerical data; D017322:Clinical Trials, Phase II as Topic / Q000941:ethics / Q000706:statistics & numerical data; D006801:Humans; D009369:Neoplasms / Q000473:pathology*; D010599:Pharmacokinetics; D012107:Research Design / Q000706:statistics & numerical data*
chemical_list: D014408:Biomarkers, Tumor