title: The relationship between MDM2 expression and tumor thickness and invasion in primary cutaneous malignant melanoma.
abstract: BACKGROUND
  Malignant melanoma is the most invasive cutaneous tumor which is associated with an incredibly high mortality rate. The most reliable histological factors associated with melanoma prognosis are tumor thickness- measured by the Breslow index- and invasion depth- measured by Clark level. Murine double minute 2 (MDM2) gene inhibits p53-dependent apoptosis. An increase in MDM2 expression has been found in many tumors. This study aimed to investigate MDM2 expression and its correlation with tumor thickness and invasion level in malignant melanoma.
  
  
  METHODS
  This study evaluated paraffin blocks from 43 randomly selected patients with primary cutaneous melanoma who referred to the main university pathology center in Isfahan, Iran. MDM2 expression rate was assessed via immunohistochemical techniques and hematoxylin and eosin staining to determine tumor thickness and invasion level. Correlations between MDM2 expression and tumor thickness and invasion were analyzed using Spearman's correlation coefficient in SPSS17.
  
  
  RESULTS
  The mean age of patients was 61.2 ± 15 years. Men and women constituted 55.8% and 44.2% of the participants, respectively. The rate of MDM2 positivity was 28.9%. MDM2 expression was directly associated with tumor thickness (r = 0.425; p = 0.002) and weakly with invasion level (r = 0.343; p = 0.01).
  
  
  CONCLUSIONS
  Despite the low MDM2 expression rate observed in this study, direct relationships between MDM2 positivity and tumor thickness and invasion level were identified. MDM2 expression can thus be suggested as a potential new predictive prognostic factor.
authors.affiliation: Professor, Department of Pathology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Parvin
authors.initials: P
authors.lastname: Rajabi
authors.forename: Paridokht
authors.initials: P
authors.lastname: Karimian
authors.forename: Mitra
authors.initials: M
authors.lastname: Heidarpour
keywords: Melanoma; Murine Double Minute 2; Prognosis