INTRODUCTION: The histopathological diagnosis of melanocytic lesions may be very difficult, even by experts within the field. The challenge can come from inaccurate and/or subjective application of the diagnosis criteria. AIM: The goal of this study was to develop a method of systematic application of histopathological criteria as a result of the most relevant microscopic characteristics. MATERIAL AND METHODS: The most important criteria to diagnosing melanoma on histopathological bases were selected and given points ranging from 1 to 5 according to their relevance to the melanoma diagnosis. A total of 101 cases of extensive-superficial melanoma less than 2mm thick were comparatively analysed with 33 benign melanocytic lesions (thirteen Spitz nevi, six Reed nevi, six dysplastic nevi, three congenital nevi, three acquired nevi, one combined nevus and one recurrent nevus). RESULTS: The total amount of values obtained on histopathological criteria (scores) pointed out significant statistical differences between benign and malignant lesions, what makes this method useful for surgical pathologist in daily routines. CONCLUSION: The objective and systematic application of histopathological criteria by means of the scoring system may be helpful in the differential diagnosis between benign and malignant melanocytic neoplasms, but the approach was not able to distinguish melanocytic lesions of unknown biological behavior.
Melanoma; Scoring system; Differential diagnosis; Spitz nevus
