title: Treatment with nephrectomy only for small, stage I/favorable histology Wilms' tumor: a report from the National Wilms' Tumor Study Group.
abstract: OBJECTIVE
  Children younger than 24 months with small (< 550 g), favorable histology (FH) Wilms tumors (WTs) were shown in a pilot study to have an excellent prognosis when treated with nephrectomy only.
  
  
  METHODS
  A study of nephrectomy only for the treatment of selected children with FH WT was undertaken. Stringent stopping rules were designed to insure closure of the study if the true 2-year relapse-free survival rate was 90% or lower.
  
  
  RESULTS
  Seventy-five previously untreated children younger than 24 months with stage I/FH WTs for which the surgical specimen weighed less than 550 g were treated with nephrectomy only. Three patients developed metachronous, contralateral WT 1.1, 1.4, and 2.3 years after nephrectomy, and eight patients relapsed 0.3 to 1.05 years after diagnosis (median, 0.4 years; mean, 0.51 years). The sites of relapse were lung (n = 5) and operative bed (n = 3). The 2-year disease-free (relapse and metachronous contralateral WT) survival rate was 86.5%. The 2-year survival rate is 100% with a median follow-up of 2.84 years. The 2-year disease-free survival rate (excluding metachronous contralateral WT) was 89.2%, and the 2-year cumulative risk of metachronous contralateral WT was 3.1%.
  
  
  CONCLUSIONS
  Children younger than 24 months treated with nephrectomy only for a stage I/FH WT that weighed less than 550 g had a risk of relapse, including the development of metachronous contralateral WT, of 13.5% 2 years after diagnosis. All patients who experienced relapse on this trial are alive at this time. This approach will be re-evaluated in a clinical trial using a less conservative stopping rule.
authors.affiliation: Department of Pediatrics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA. daniel.green@roswellpark.org
authors.forename: D M
authors.initials: DM
authors.lastname: Green
authors.forename: N E
authors.initials: NE
authors.lastname: Breslow
authors.forename: J B
authors.initials: JB
authors.lastname: Beckwith
authors.forename: M L
authors.initials: ML
authors.lastname: Ritchey
authors.forename: R C
authors.initials: RC
authors.lastname: Shamberger
authors.forename: G M
authors.initials: GM
authors.lastname: Haase
authors.forename: G J
authors.initials: GJ
authors.lastname: D'Angio
authors.forename: E
authors.initials: E
authors.lastname: Perlman
authors.forename: M
authors.initials: M
authors.lastname: Donaldson
authors.forename: P E
authors.initials: PE
authors.lastname: Grundy
authors.forename: R
authors.initials: R
authors.lastname: Weetman
authors.forename: M J
authors.initials: MJ
authors.lastname: Coppes
authors.forename: M
authors.initials: M
authors.lastname: Malogolowkin
authors.forename: P
authors.initials: P
authors.lastname: Shearer
authors.forename: P
authors.initials: P
authors.lastname: Coccia
authors.forename: M
authors.initials: M
authors.lastname: Kletzel
authors.forename: P R
authors.initials: PR
authors.lastname: Thomas
authors.forename: R
authors.initials: R
authors.lastname: Macklis
authors.forename: G
authors.initials: G
authors.lastname: Tomlinson
authors.forename: V
authors.initials: V
authors.lastname: Huff
authors.forename: R
authors.initials: R
authors.lastname: Newbury
authors.forename: D
authors.initials: D
authors.lastname: Weeks
mesh_terms: D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009392:Nephrectomy; D010865:Pilot Projects; D011379:Prognosis; D009396:Wilms Tumor / Q000401:mortality / Q000473:pathology / Q000601:surgery*