title: Indications of Sentinel Node Biopsy in Thin Melanoma.
abstract: OBJECTIVE
  To assess data on survival, recurrence and histological factors in positive and negative sentinel lymph nodes in thin melanoma cases.
  
  
  METHODS
  A systematic review was conducted on observational studies in four databases (Cochrane Library, Medline, Embase and Lilacs). Positive and negative micrometastases in sentinel lymph node biopsy were compared regarding the clinical outcomes - death and recurrence - and six histological factors - vertical growth phase, Breslow thickness, Clark level, ulceration, regression and mitosis rate.
  
  
  RESULTS
  Positive sentinel lymph node is statistically associated with greater risk of death in six studies (OR: 7.2; 95%CI [2.37-21.83]; I2 0%) and also to recurrence in three studies (OR: 30.7; 95%CI [12.58-74.92]; I2 36%). Comparing positive and negative groups, the histological factors predicting positive sentinel nodes and poor prognosis were: mitosis rate ≥ 5/mm2 (OR: 16.29; 95%CI [3.64-72.84]; I2 40%); VGP (OR: 2.93; 95%CI [1.08-7.93]; I2 59%); Breslow thickness ≥ 0.75mm (OR: 2.23; 95%CI [1.29-3.86]; I2 0%); and Clark level IV-V (OR: 1.61; 95%CI [1.06-2.44]; I234%).
  
  
  CONCLUSIONS
  The statistically significant results associated with the presence of micrometastases in thin melanomas were Breslow thickness ≥ 0.75 mm, Clark level IV-V and mitoses ≥ 5/mm2, absence of regression. This histological factor of ulceration was associated, but not statistically significant.
authors.affiliation: Resident in Dermatology, Universidade Federal de São Paulo - UNIFESP, São Paulo, SP, BR.
authors.forename: Fernanda Braga
authors.initials: FB
authors.lastname: Silva
authors.affiliation: Department of Plastic Surgery, Universidade Federal de São Paulo - UNIFESP, São Paulo, SP, BR.
authors.forename: Renato Santos de
authors.initials: RS
authors.lastname: Oliveira Filho
authors.affiliation: Centro Cochrane do Brasil, São Paulo, SP, BR.
authors.forename: Wagner
authors.initials: W
authors.lastname: Iared
authors.affiliation: Centro Cochrane do Brasil, São Paulo, SP, BR.
authors.forename: Álvaro Nagib
authors.initials: ÁN
authors.lastname: Atallah
authors.affiliation: Department of Plastic Surgery, Universidade Federal de São Paulo - UNIFESP, São Paulo, SP, BR.
authors.forename: Ivan Dunchee de Abranches Oliveira
authors.initials: ID
authors.lastname: Santos
authors.affiliation: Department of Surgery, Universidade Federal de São Paulo - UNIFESP, São Paulo, SP, BR.
authors.forename: Lydia Masako
authors.initials: LM
authors.lastname: Ferreira