EPILUMINESCENCE MICROSCOPY - CRITERIA OF CUTANEOUS MELANOMA PROGRESSION

Background: Cutaneous melanoma develops through a series of evolutiona ry steps (intraepidermal, radial, and vertical growth phases) that are traceable in specific histologic features. Epiluminescence microscopy (ELM) is an in vivo technique that enables the visualization of morph ologic structures in pigmented lesions correlated with specific histol ogic architectural characteristics. Many ELM criteria associated with cutaneous melanoma have been described, but their correlation with tum or progression has not yet been established. Objective: In this prelim inary study our purpose was to explore the possibility of recognizing ELM criteria that allow the in vivo detection of the various phases of melanoma progression as well as tumor depth. Methods: Seventy-two cut aneous melanomas (41 ''thin'' melanomas [TnM], < 0.76 mm thickness, an d 31 ''thick'' melanomas [TkM], > 0.75 mm thickness) were investigated with ELM for the presence of nine standard ELM criteria; their signif icance was determined by calculating the chi-square test of independen ce. Results: A significant association is found between the presence o f pigment network and TnM and between the presence of gray-blue areas, vascular pattern, and TkM. Moreover, pigment network plus radial stre aming is the most significant association of ELM criteria in TnM, wher eas gray-blue areas plus vascular pattern is the greatest in TkM. Conc lusion: This study shows a good correlation between certain ELM criter ia and the histologic architecture of cutaneous melanoma for a preoper ative evaluation of the tumor thickness. Further investigation is need ed for verifying on a larger number of cases our pilot estimates of se nsitivity and specificity of ELM criteria in thin and thick melanomas.