title: Nephron sparing surgery (NSS) for unilateral wilms tumor (UWT): the SIOP 2001 experience.
abstract: BACKGROUND
  Total nephrectomy (TN) remains the standard treatment of unilateral Wilms tumors (uWT). The SIOP WT-2001 protocol allowed Nephron Sparing Surgery (NSS) for polar or peripherally non-infiltrating tumors.
  
  
  OBJECTIVE
  Inventory of the current SIOP NSS-experience.
  
  
  METHODS
  2,800 patients with a unilateral, localized or metastatic and an unequivocal surgical technique recorded were included. All had neo-adjuvant chemotherapy and delayed surgery. In 91 (3%) NSS was performed and in 2709 TN. Data was retrieved from the SIOP WT 2001 database.
  
  
  RESULTS
  NSS group contained 65% stage I tumours and the TN group 48%. Tumor volume (at diagnosis and surgery) was significantly smaller in the NSS group. Within stage III, after NSS, 7/12 (58%) had positive margins (M +), 5 with tumor negative lymph nodes (LN-). After TN, 355/712 (55%) had M + , 182 were LN-. Treatment of M+ in the NSS group resulted in two conversions to TN (one combined with radiotherapy), three patients had radiotherapy only and in two patients local therapy, if given, was not recorded. After NSS, four recurrences occurred. For localized disease the 5-year overall (OS) and event free survival (EFS) in NSS group was 100 and 94.8 (95% CI:89.9-99.9), respectively, while OS and EFS in the TN group were 94.4 (95% CI: 93.2-95.5, log-rank test P = 0.06) and 86.5 (95% CI:85.0-88.1, log-rank test P = 0.06), respectively.
  
  
  CONCLUSIONS
  NSS was only performed in 3% of patients with uWT. Despite excellent survival with few relapses, the gain of nephrons needs to be weighed against the risk to induce stage III with intensified therapy.
authors.affiliation: Pediatric Surgical Center of Amsterdam, Emma Children's Hospital AMC and VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Jim C H
authors.initials: JC
authors.lastname: Wilde
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Aronson
authors.forename: Beata
authors.initials: B
authors.lastname: Sznajder
authors.forename: Harm
authors.initials: H
authors.lastname: Van Tinteren
authors.forename: Mark
authors.initials: M
authors.lastname: Powis
authors.forename: Bruce
authors.initials: B
authors.lastname: Okoye
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cecchetto
authors.forename: Georges
authors.initials: G
authors.lastname: Audry
authors.forename: Jörg
authors.initials: J
authors.lastname: Fuchs
authors.forename: Dietrich Von
authors.initials: DV
authors.lastname: Schweinitz
authors.forename: Hugo
authors.initials: H
authors.lastname: Heij
authors.forename: Norbert
authors.initials: N
authors.lastname: Graf
authors.forename: Christophe
authors.initials: C
authors.lastname: Bergeron
authors.forename: Kathy
authors.initials: K
authors.lastname: Pritchard-Jones
authors.forename: Marry
authors.initials: M
authors.lastname: Van Den Heuvel-Eibrink
authors.forename: Modesto
authors.initials: M
authors.lastname: Carli
authors.forename: Foppe
authors.initials: F
authors.lastname: Oldenburger
authors.forename: Bengt
authors.initials: B
authors.lastname: Sandstedt
authors.forename: Jan
authors.initials: J
authors.lastname: De Kraker
authors.forename: Jan
authors.initials: J
authors.lastname: Godzinski
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D003609:Dactinomycin / Q000627:therapeutic use; D005500:Follow-Up Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D009367:Neoplasm Staging; D009392:Nephrectomy; D009399:Nephrons / Q000601:surgery*; D059351:Organ Sparing Treatments; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate; D014750:Vincristine / Q000627:therapeutic use; D009396:Wilms Tumor / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000601:surgery*
chemical_list: D003609:Dactinomycin; D014750:Vincristine
keywords: Wilms tumor; nephroblastoma; nephron sparing surgery; partial nephrectomy; unilateral Wilms tumor; unilateral nephroblastoma