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.
