Tumor and inflammation markers in melanoma using tissue microarrays: a validation study.

The importance of tumor immune response is ever more evident in melanoma carcinogenesis. One approach to explore the pathological mechanisms involved in such immune responses, and to analyze other tumor prognostic markers in melanoma, is to use tissue microarrays (TMAs). However, TMA technology remains to be adequately validated in this setting. Protein expression patterns in whole slides and TMA sections from 34 melanoma patients were compared for a number of inflammation and tumor cell markers using immunohistochemical stains against CD8 (lymphocytes), CD163 (macrophages), micropthalmia transcription factor, N-cadherin, melanoma cell-adhesion molecule, and c-kit protein (CD117). Using simplified versions of previously published grading systems, the agreement between TMA and whole slide sections ranged between 83 and 96%, and between 81 and 97% for inflammation and tumor cell markers, respectively. We conclude that TMA technology combined with simplified grading systems are appropriate for analyzing both inflammation and tumor cell markers in melanoma.