title: Thin melanomas with unusual aggressive behavior: a report on nine cases. Melanoma Group of French Federation of Cancer Centers.
abstract: BACKGROUND
  The major factor influencing the prognosis of cutaneous malignant melanoma (MMs) is the maximum thickness of the tumor as measured by Breslow's method. However, it has been reported that thin melanomas, which should have an excellent prognosis, may have the potential to metastasize, some with an unusually rapid course.
  
  
  OBJECTIVE
  Our purpose was to examine prognostic indicators in relation to unusually rapid aggressive behavior in patients with thin MMs (<0.76mm).
  
  
  METHODS
  We describe nine cases of thin MM (<.76mm) that exhibited a recurrence or metastasis during a follow-up period ranging from 3 to 10 years, among computerized records of 1118 MMs treated in a multicenter epidemiologic study. The data obtained from these nine cases were compared with nonrecurring thin MM (149 cases) of the same cohort.
  
  
  RESULTS
  The particular aggressiveness of these thin melanomas was reflected by the short disease-free interval (3 years or less) in all ine patients. The recurring thin MM more frequently involved head and neck sites, occurred in male patients, and showed Clark's level III and IV.
  
  
  CONCLUSIONS
  Our review suggests that the head and neck area is particularly involved by unusually rapidly recurring thin MM. Possible explanations are the specific problems of surgical management and the greater sun exposure of this location.
authors.affiliation: Centre Rene Hugguenin, Saint-Cloud, France.
authors.forename: C
authors.initials: C
authors.lastname: Vilmer
authors.forename: C
authors.initials: C
authors.lastname: Bailly
authors.forename: V
authors.initials: V
authors.lastname: Le Doussal
authors.forename: S
authors.initials: S
authors.lastname: Lasry
authors.forename: P
authors.initials: P
authors.lastname: Guerin
authors.forename: M M
authors.initials: MM
authors.lastname: Delaunay
authors.forename: A M
authors.initials: AM
authors.lastname: Mandard
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000473:pathology / Q000556:secondary; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008545:Melanoma / Q000473:pathology* / Q000556:secondary; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009367:Neoplasm Staging; D011379:Prognosis; D012737:Sex Factors; D012878:Skin Neoplasms / Q000473:pathology*; D015996:Survival Rate