title: Older age is an adverse prognostic factor in stage I, favorable histology Wilms' tumor treated with vincristine monochemotherapy: a study by the United Kingdom Children's Cancer Study Group, Wilm's Tumor Working Group.
abstract: OBJECTIVE
  To identify clinical prognostic factors in children with stage I, favorable histology (FH) Wilms' tumor treated with vincristine monochemotherapy after immediate nephrectomy to define subgroups for consideration of further reduction in treatment intensity.
  
  
  METHODS
  During two consecutive trials of the United Kingdom Children's Cancer Study Group (UKW2 and UKW3, 1986 to 2001), 242 children with stage I FH Wilms' tumor were treated with immediate nephrectomy followed by 10 weekly injections of vincristine 1.5 mg/m2. Event-free survival (EFS) and overall survival (OS) were compared by age group.
  
  
  RESULTS
  The 4-year EFS rate was 93.2%, 87.2%, and 71.3% for children less than 2 years old, 2 to 4 years old, and 4 years old or older at diagnosis, respectively (log-rank, P =.001); the corresponding 4-year OS rate was 98.1%, 95.0%, and 87.2% (log-rank, P =.01). There were no toxicity- or procedure-related deaths. In multivariate analysis, specimen weight was not of independent prognostic value (P =.66). Among the 186 children younger than 4 years at diagnosis, there were 17 relapses and five deaths, compared with 16 relapses and eight deaths among the 56 children at least 4 years old at diagnosis. OS after relapse was surprisingly poor (61.6% at 4 years).
  
  
  CONCLUSIONS
  Treatment for stage I FH Wilms' tumor is generally successful using vincristine monotherapy after immediate nephrectomy, and therefore, the risks of dactinomycin hepatopathy can be avoided. However, age at least 4 years is a significant adverse prognostic factor. This treatment schedule should be considered in any trial of treatment reduction in very young children with stage I FH Wilms' tumor, regardless of tumor size, and we suggest that the upper age limit for the reduced therapy be set at 4 years.
authors.affiliation: Department of Paediatric Oncology, Royal Marsden Hospital/Institute of Cancer Research, Brookes Lawley Bldg, Cotswold Rd, Sutton, Surrey, SM2 5NG, United Kingdom. kathy.pritchard-jones@icr.ac.uk.
authors.forename: K
authors.initials: K
authors.lastname: Pritchard-Jones
authors.forename: A
authors.initials: A
authors.lastname: Kelsey
authors.forename: G
authors.initials: G
authors.lastname: Vujanic
authors.forename: J
authors.initials: J
authors.lastname: Imeson
authors.forename: C
authors.initials: C
authors.lastname: Hutton
authors.forename: C
authors.initials: C
authors.lastname: Mitchell
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000972:Antineoplastic Agents, Phytogenic / Q000009:adverse effects / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D018450:Disease Progression; D005260:Female; D006801:Humans; D007223:Infant; D007680:Kidney Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery; D008297:Male; D009392:Nephrectomy; D011379:Prognosis; D016016:Proportional Hazards Models; D018709:Statistics, Nonparametric; D015996:Survival Rate; D016896:Treatment Outcome; D006113:United Kingdom; D014750:Vincristine / Q000009:adverse effects / Q000627:therapeutic use*; D009396:Wilms Tumor / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D014750:Vincristine