[Epiluminescent microscopy aspects of initial cutaneous melanoma metastases]

Especially small and initial cutaneous melanoma metastases (CMMs) are tumours with inconspicuous clinical and sometimes histological features which may be difficult to differentiate from other melanocytic lesions. The present study was performed to determine whether epiluminescence microscopic (ELM) criteria could increase the accuracy in preoperative evaluation of CMMs.

Thirty photographed and histologically verified CMMs were examined retrospectively using ELM in order to visualize a multitude of morphological features permitting the recognition of malignancy. The colour slides obtained by the photography were subjected to a secondary 30-80 fold magnification in order to conduct a visual analysis. The 50 naevi in the control group were all histologically benign.

Five of the 15 features studied were shown to differ significantly between the two groups. Polymorphic angiectatic base pattern and vascular aneurysms, areas of polymorphic and horizontally dilated capillaries, peripheral erythema, saccular pattern and a light brown halo had a specificity of 90-98% and a sensitivity of 40-46% for CMMs (p<0.001). Peripheral grayish patches, lesions surrounded by gray streaks and microscopic ovoid blood lakes were absent in the benign group.

The prevalence of distinct ELM criteria in CMMs enhances the diagnostic accuracy of malignancy in melanocytic skin lesions.