Expresia imunohistochimică a markerilor melanocitari în țesut normal și în melanomul cutanat malign

Abstract

Background Melanocytes are neural crest – derived pigment – producing cells located in the basal epidermal layer and in other anatomical structures, such as the ocular choroid, the inner ear, and the central nervous system. Their primary role is melanin synthesis, providing photoprotection from ultraviolet (UV) radiation. Cutaneous malignant melanoma (CMM) represents one of the most aggressive forms of skin cancer, with an increasing incidence, particularly among fair-skinned populations. Early and accurate diagnosis is critical for patient survival, and immunohistochemistry (IHC) remains a cornerstone in differentiating melanocytic neoplasms. Material and methods This narrative review synthesizes evidence from the international literature (PubMed, Scopus, Web of Science) published up to 2024, focusing on IHC marker expression in normal melanocytes and CMM. Eligible sources included peer-reviewed original research, clinical studies, systematic reviews, and meta-analyses published in English. Particular emphasis was placed on studies evaluating S-100, SOX10, Melan-A, HMB-45, MITF, BCL-2, HER2, E-cadherin, p53, p57, and Ki-67. Results S-100 and SOX10 emerged as highly sensitive markers, whereas Melan-A and HMB-45 demonstrated greater specificity. BCL-2, p57, and Ki-67 correlated with tumor aggressiveness and metastatic potential. HER2 and p53 showed variable expression with limited diagnostic and prognostic applicability. Loss of E-cadherin was associated with increased invasive behavior. The use of combined IHC panels enhanced diagnostic accuracy, particularly in challenging subtypes such as amelanotic, desmoplastic, and morphologically atypical melanomas. Conclusions IHC markers are indispensable for diagnostic workup, prognostic assessment, and therapeutic decision-making. No single marker is sufficient; therefore, integrated panels in conjunction with molecular profiling offer superior stratification and support personalized management strategies. Nevertheless, early detection remains the key factor in improving clinical outcomes.